Dynoing out the myth of Intake mods: The Results
#1
12-16-2010, 03:11 PM
Dynoing out the myth of Intake mods: The Results
here is the long awaited (for some) thread.
First, I’d like to state that it’s always been my goal to give back to the community that has given so much to me. I really appreciate everything
and hope someone finds this useful.
Having such little independent data available for aftermarket intakes, it was difficult for me to make a choice on which would work best for me.
I had completed my bolt-ons except for the intake. I have headers, highflow cats, and catback; I also have a tune.
I had the standard setup; a Z-tube and K&N drop-in filter. You always hear from everyone that this is where to start when you are looking for
more power. It’s cheap and easy. I felt that I was at a point where there was surely a way to squeeze some more power out of the engine.
Typically with other motors, intakes will net a decent amount of power. I’m not sure whether to attribute this to the fact that other motors
are detuned for fuel efficiency, or just less R&D from the factory; however, the general sentiment seemed to be that intakes do little to nothing
on our cars except make noise. In total disbelief (mainly due to the lack of hard evidence and independent testing) I set out to finally find out
the truth about intakes on the VQ35DE.
In order to determine which intake setup works best with my car, and the mods I currently have, I set out to clear up the misinformation
of aftermarket intakes and gain some knowledge of how intakes perform on the VQ35DE. It is my opinion that this testing will benefit others by
helping them make a decision on which intake to get as it will likely perform similarly on their cars.
I feel that the best way to isolate the intake in testing is to eliminate as many bottlenecks in the rest of the system as possible. For this
reason, I waited to finish my bolt-ons before choosing an intake. The specs of the vehicle that was tested are as follows:
06 G35 5AT with 46,XXX miles
- Z-Tube
- K&N Drop-in filter
- Ported and Polished Plenum Assembly down to the runners
- Thermal gaskets to lower plenum temps
- Coolant Bypass mod work thread
- Strup coated headers
- Altered Atmosphere HiFlow Cats
- Bassani true dual exhaust with x-pipe
- Uprev Osiris (e-tune performed when car had Z-Tube, K&N, AAM HFC, Bassani TD)
I setup a methodology of testing: I needed some guidelines to adhere to in order to achieve accurate results and be able to get reliable
data. I got in contact with people more knowledgeable than myself with the way this sort of testing should be done and established this set of
testing rules. The people involved in creating this set of rules included: the manufacturers of the intakes, a certified infiniti tech, multiple
people on the G35driver and my350z Forums, and myself.
I tried to create a level “playing field” for all the intakes by keeping the variables to a minimum.
- The Vehicle remained strapped during the entire 6 hour testing period
- The dyno cooling fans were blowing on the car at a constant speed; the angle in which they blew also stayed the same.
- The hood remained open, to help rule out heat soak on the intakes
- Before switching each intake the battery cable was disconnected and the brake pedal was pressed and held for 10 seconds (this is the
known procedure for clearing the g35/350z ECU)
- Each intake was given the same amount of time to cool down, and the same amount of learning time (around 30 minutes cool down, 10
minutes learning)
- The ambient temperature range and humidity was relatively stable at 77 – 81 degrees F and 20 – 22 %, respectively
- The intake air temperatures were monitored to make sure each intake wasn’t suffering from heatsoak
- Each intake was given at least 3 good runs, if there were any spikes or oddities it was discarded and ran again. By the 3rd run heat soak
became a variable. The first and second runs were always the highest.
- Engine Coolant temps were also kept stable between intakes
- Each intake was to be data logged with Osiris Cipher
- Each intake was to have a sound recording done (2 feet away from engine, same location every time)
I was consistent in following this set of procedures for each intake, including the stock. Even before my first run the ECU was cleared.
I also dynoed the stock setup again at the end (albeit with a paper filter instead of the K&N) to verify the dynos accuracy and to make sure
there weren’t any ghosting effects that may be noticed from switching out intakes.
Now that I had the groundwork laid out, I went to work trying to find as many intakes as I could for testing. I posted on the forums,
emailed manufacturers, and reached out to people who would be willing to donate an intake for testing. I made it clear that I had no intent on
keeping the intake - I wasn’t looking for hand outs. I was, however, willing to do a full review to any manufacturer who would send me an intake in
addition to including them in the testing.
Nearly every manufacturer I emailed ignored me. Although there were a few who responded, of these few, one mentioned they already had
sufficient independent testing, but when I asked to see it, I was ignored. There were, however, three companies and one G35driver vendor who
agreed to send me intakes for testing. I am thankful for the chance to demo their product and look forward to working with them in the future
they are all great guys and regardless of the results, I enjoyed meeting with them.
Companies I emailed:
- R2C - http://www.r2cperformance.com - responded, no to testing
- Fujita - http://www.f5air.com - no response
- AEM - http://www.aemintakes.com - no response
- Injen - http://www.injen.com/ - no response
- Takeda - http://wwww.afepower.com - responded, received intake
- K&N - http://www.knfilters.com - no response
- HKS - http://www.hksusa.com - no response
- Weapon-R - http://weapon-r.com - responded, received intake
- Stillen - http://www.stillen.com - no response
- Kinetix - http://www.kinetixracing.com - no response
- TopSpeed - http://www.topspeedauto.com - responded, received intake
- Motordyne - http://www.motordyneengineering.com – no response (inquired about using ART pipes for testing since some believed the HFC were a
bottleneck in my system)
- MartyG – G35Driver.com Vendor – responded, received intake
As I mentioned, I reached out to people locally who had already purchased an intake. I informed them of my testing and I had a huge response
from the DFW G Club. I was able to secure a large number of intake setups from people in the area who were happy to help. I’m proud to be part of a
car club that has so many great members in it. It is nearly impossible to find people who will go the distance to help someone they barely know, yet
there were so many DFW guys who were willing to chip in and help out.
So, with the intake pieces I already owned, the ones shipped to me from out of state, and all the local ones I was able to borrow, I amassed
quite a list:
- Motordyne Mrev2 Lower (duelper4mance)
- Ported and Polished Lower (my own design based off of mrev2)
- Motordyne 5/16 Spacer (duelper4mance)
- Skunk2 5/8 Spacer
- Ported and Polished Upper (my own design)
- Z-Tube
- K&N Panel Filter
- New Sealed OEM Paper Filter (duelper4mance)
- The stock airbox
- JWT Pop charger
- Injen SRI (firefox)
- Stillen Intake (R1Forever)
- FuRookie SRI (martyg35)
- Tekada (Platelock, V1)
- Tekada (AFE – V2, uses stock box)
- Weapon-R
- Top Speed intake (waijai and Aaron from topspeed)
First, I’d like to state that it’s always been my goal to give back to the community that has given so much to me. I really appreciate everything
and hope someone finds this useful.
Having such little independent data available for aftermarket intakes, it was difficult for me to make a choice on which would work best for me.
I had completed my bolt-ons except for the intake. I have headers, highflow cats, and catback; I also have a tune.
I had the standard setup; a Z-tube and K&N drop-in filter. You always hear from everyone that this is where to start when you are looking for
more power. It’s cheap and easy. I felt that I was at a point where there was surely a way to squeeze some more power out of the engine.
Typically with other motors, intakes will net a decent amount of power. I’m not sure whether to attribute this to the fact that other motors
are detuned for fuel efficiency, or just less R&D from the factory; however, the general sentiment seemed to be that intakes do little to nothing
on our cars except make noise. In total disbelief (mainly due to the lack of hard evidence and independent testing) I set out to finally find out
the truth about intakes on the VQ35DE.
In order to determine which intake setup works best with my car, and the mods I currently have, I set out to clear up the misinformation
of aftermarket intakes and gain some knowledge of how intakes perform on the VQ35DE. It is my opinion that this testing will benefit others by
helping them make a decision on which intake to get as it will likely perform similarly on their cars.
I feel that the best way to isolate the intake in testing is to eliminate as many bottlenecks in the rest of the system as possible. For this
reason, I waited to finish my bolt-ons before choosing an intake. The specs of the vehicle that was tested are as follows:
06 G35 5AT with 46,XXX miles
- Z-Tube
- K&N Drop-in filter
- Ported and Polished Plenum Assembly down to the runners
- Thermal gaskets to lower plenum temps
- Coolant Bypass mod work thread
- Strup coated headers
- Altered Atmosphere HiFlow Cats
- Bassani true dual exhaust with x-pipe
- Uprev Osiris (e-tune performed when car had Z-Tube, K&N, AAM HFC, Bassani TD)
I setup a methodology of testing: I needed some guidelines to adhere to in order to achieve accurate results and be able to get reliable
data. I got in contact with people more knowledgeable than myself with the way this sort of testing should be done and established this set of
testing rules. The people involved in creating this set of rules included: the manufacturers of the intakes, a certified infiniti tech, multiple
people on the G35driver and my350z Forums, and myself.
I tried to create a level “playing field” for all the intakes by keeping the variables to a minimum.
- The Vehicle remained strapped during the entire 6 hour testing period
- The dyno cooling fans were blowing on the car at a constant speed; the angle in which they blew also stayed the same.
- The hood remained open, to help rule out heat soak on the intakes
- Before switching each intake the battery cable was disconnected and the brake pedal was pressed and held for 10 seconds (this is the
known procedure for clearing the g35/350z ECU)
- Each intake was given the same amount of time to cool down, and the same amount of learning time (around 30 minutes cool down, 10
minutes learning)
- The ambient temperature range and humidity was relatively stable at 77 – 81 degrees F and 20 – 22 %, respectively
- The intake air temperatures were monitored to make sure each intake wasn’t suffering from heatsoak
- Each intake was given at least 3 good runs, if there were any spikes or oddities it was discarded and ran again. By the 3rd run heat soak
became a variable. The first and second runs were always the highest.
- Engine Coolant temps were also kept stable between intakes
- Each intake was to be data logged with Osiris Cipher
- Each intake was to have a sound recording done (2 feet away from engine, same location every time)
I was consistent in following this set of procedures for each intake, including the stock. Even before my first run the ECU was cleared.
I also dynoed the stock setup again at the end (albeit with a paper filter instead of the K&N) to verify the dynos accuracy and to make sure
there weren’t any ghosting effects that may be noticed from switching out intakes.
Now that I had the groundwork laid out, I went to work trying to find as many intakes as I could for testing. I posted on the forums,
emailed manufacturers, and reached out to people who would be willing to donate an intake for testing. I made it clear that I had no intent on
keeping the intake - I wasn’t looking for hand outs. I was, however, willing to do a full review to any manufacturer who would send me an intake in
addition to including them in the testing.
Nearly every manufacturer I emailed ignored me. Although there were a few who responded, of these few, one mentioned they already had
sufficient independent testing, but when I asked to see it, I was ignored. There were, however, three companies and one G35driver vendor who
agreed to send me intakes for testing. I am thankful for the chance to demo their product and look forward to working with them in the future
they are all great guys and regardless of the results, I enjoyed meeting with them.
Companies I emailed:
- R2C - http://www.r2cperformance.com - responded, no to testing
- Fujita - http://www.f5air.com - no response
- AEM - http://www.aemintakes.com - no response
- Injen - http://www.injen.com/ - no response
- Takeda - http://wwww.afepower.com - responded, received intake
- K&N - http://www.knfilters.com - no response
- HKS - http://www.hksusa.com - no response
- Weapon-R - http://weapon-r.com - responded, received intake
- Stillen - http://www.stillen.com - no response
- Kinetix - http://www.kinetixracing.com - no response
- TopSpeed - http://www.topspeedauto.com - responded, received intake
- Motordyne - http://www.motordyneengineering.com – no response (inquired about using ART pipes for testing since some believed the HFC were a
bottleneck in my system)
- MartyG – G35Driver.com Vendor – responded, received intake
As I mentioned, I reached out to people locally who had already purchased an intake. I informed them of my testing and I had a huge response
from the DFW G Club. I was able to secure a large number of intake setups from people in the area who were happy to help. I’m proud to be part of a
car club that has so many great members in it. It is nearly impossible to find people who will go the distance to help someone they barely know, yet
there were so many DFW guys who were willing to chip in and help out.
So, with the intake pieces I already owned, the ones shipped to me from out of state, and all the local ones I was able to borrow, I amassed
quite a list:
- Motordyne Mrev2 Lower (duelper4mance)
- Ported and Polished Lower (my own design based off of mrev2)
- Motordyne 5/16 Spacer (duelper4mance)
- Skunk2 5/8 Spacer
- Ported and Polished Upper (my own design)
- Z-Tube
- K&N Panel Filter
- New Sealed OEM Paper Filter (duelper4mance)
- The stock airbox
- JWT Pop charger
- Injen SRI (firefox)
- Stillen Intake (R1Forever)
- FuRookie SRI (martyg35)
- Tekada (Platelock, V1)
- Tekada (AFE – V2, uses stock box)
- Weapon-R
- Top Speed intake (waijai and Aaron from topspeed)
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Top Answer
12-16-2010, 03:13 PM
Next was locating a dyno for testing. I had originally dynoed at Cobb tuning in Plano in a Z vs G dyno day back in December 2009, so I had
a baseline there. I emailed them first asking for pricing for my project. It was a bit high, but I was ready to forgo the expense to do the testing.
Luckily, G35driver member Duelper4mance suggested I contact Steve Kan of Kan Tuning. He was able to get me rates that better fit my budget and
allowed me to test all the intakes I had. Although he races RX7s, he was also a G35 owner so I think that helped. I’m very glad I got to meet Steve;
he is a very experienced tuner who had a lot of insight to offer during my testing. With Steve in the driver’s seat, I felt like the testing was taken
to a higher level than what I could have achieved on my own. He was really an asset to the testing.
After lining up a date for the dyno test, I prepared for testing. We made an event out of the day and many members of the DFW G Club got
together at his shop. While I wasn’t able to enjoy hanging out with everyone as much as I would have liked, I’m glad everyone who was able to see
the results. So not only did Steve and I have verification of the results, but around 12 other people showed up who can testify about the way the
testing was handled.
On October 30th the testing took place at Kan Tuning in Fort Worth, TX. We started around 12:30 and finished up after 6:00pm. Everything went
smoothly from what I could tell - there were no major issues to speak of. There were a few codes thrown when I forgot a vacuum hose before one run,
and another time when I put the MAF sensor in backwards. But I fixed the problems, cleared the codes with Cipher and continued testing. By the end of
the day I had ascertained a good bit of information of how various intakes affect performance of my engine. I was excited at all the data I had
gathered, and the power I had gained from the finding the best combination of intake parts for my engine.
I originally felt confident that I had finally discovered the best setup for my car at this point in my build. The problem was, the more I
looked at the data the more variables came up that I had no control over.
I had come to find that the full story of the intakes was not uncovered. No, I was just at the surface level of the story and the real
meaning of what was happening was still hidden from my understanding.
I’m sure by now you have probably stopped reading and are scrolling around looking for the dyno sheets to see which intake is the best.
That’s what this whole thing is about, right? Well I purposely formatted my report in this way, so that you try to understand the meaning of my
findings instead of taking the dyno numbers at face value. Just stay with me a little longer and I promise you’ll get to the data.
From what I can tell, system performance is HIGHLY dependent on the how the MAF is calibrated. When I put an aftermarket intake on it
caused the MAF to read more air coming in compared to the stock box. In Cipher there is a mass g/sec reading that comes from the MAF sensor. Most
aftermarket intakes caused this number to be higher than stock. Now the tricky part was to determine if the amount of air going in to the engine
was accurate based on the MAF, or if there was some other factor causing the MAF to read a higher amount of air than what was actually going into
the engine.
The only sign I had that the engine wasn’t getting as much air as the MAF was saying, was my Air to Fuel ratios. On some intakes my A/F Ratios
got very low (into the 10s). It seemed my engine was dumping fuel into the chamber and expecting a specific amount of air to be there (based on the
MAF signal) however with the low A/F Ratios I was seeing, I was led to believe it wasn’t actually getting the large amounts of air the MAF was saying
it was.
My theory for why this was happening stems from two possible sources:
First, for intakes that didn’t use the stock MAF housing, I think there was a MAF scaling issue. I’ve done research on NA builds and it is
known that with a 3” MAF housing and the appropriate tuning and calibration you can realize a HP gain of 5 – 10 HP depending on supporting mods.
Without tuning and calibration the ECU cannot adapt to a MAF housing that is a different size than the stock one. Whether larger or smaller, the
ECU will likely have issue with adapting to a MAF housing that isn’t the same size as the stock housing.
The second possibility has to do with air turbulence causing inaccurate MAF readings. I was able to prove a power loss on my setup when
doing a dyno run without the air filter. You would think that having less restriction would lead to gains, however the opposite occurred. This
is why I think the Stock panel filter or a K&N (in the stock air box) perform a specific smoothing effect on the air that the stock MAF is calibrated
for. With cone shaped filters attached to the intake tube, the air enters the tube at a different angle compared to stock. Being calibrated to read
air coming in to the tube one way, it is probably the case that the MAF is misreading the amount of air when using a cone type filter.
I think with tuning and calibration it’s possible to fix both of these issues in order to gain power.
I feel like the ECU, being designed to run and learn with the stock intake installed, probably learns faster with the stock intake compared
to when it had an aftermarket intake on. So, in the shorter learning periods in which they were tested (ie: not days of learning which would be
preferred), the stock box had the advantage over aftermarket. I think it’s possible that with more learning time, the car would adapt and possibly
make more power than the dyno plots showed.
Since I was paying for the dyno out of pocket, I wasn’t able to spend a whole day there, 6 hours already cost me around $500 - I simply could
not afford to spend more time. I tried to give each intake a fair chance, and there was a definite variation between each. It was immediately clear
on the dyno which intake was on. It wasn’t like the numbers were all over the place; they were quite consistent for each intake.
But to conclude this write up, from the data I have gathered, aftermarket intakes will need tuning at the very least to make power on my
vehicle. I think it’s slightly misleading that most intake manufacturers advertise gains with intakes, and I was not able to prove them. I would
love to have been able to tune each intake on my car to see its maximum potential, but I think the average person buying an intake will not factor
tuning in when they are purchasing an intake. They will likely expect power gains and probably be let down when they see this data.
Is there another factor that could account for these losses?
Just in the time of writing this I came up with a new theory of why intakes may have underperformed on my setup. I think it’s possible that
intake manufacturers know the cars run a bit lean from the factory and they engineer the intake to trick the MAF in order to add fuel. I’m positive
in this case it would put the AFRs to a level that would increase power over the stock setup. Now my engine was already tuned so on the stock box
the AFRs were around 12.8 where they should be; when we added intakes on my setup they got very rich. On a stock tuned VQ35DE the AFRs would be in
the high 13s and I think it’s possible that the intakes causing the AFR’s to drop into the high 12’s would show a power gain. Now this power gain
wouldn’t be anything the intake is actually doing to get more air in the car, but just improving on the stock AFR by tricking the ECU. So without
tuning it may be beneficial to add an intake to your setup. This doesn’t mean the Aftermarket is better or worse than the stock box by any means,
but it could be a viable way to add power with bolt-ons before a tune. Something I hadn’t considered until just now.
click here to see data
* For donations to cover Dyno Fee and further my intake testing, Please send as a gift in paypal to: Raider2043@hotmail.com *
THANK YOU FOR YOUR CONTRIBUTION:
ITNKICN - $100!!!
gword256 - $45!!
gabe3d - $25!
Ninja1 - $20!
obender66 - $10
SwivelHips - $10
NFSP G35 - $5
a baseline there. I emailed them first asking for pricing for my project. It was a bit high, but I was ready to forgo the expense to do the testing.
Luckily, G35driver member Duelper4mance suggested I contact Steve Kan of Kan Tuning. He was able to get me rates that better fit my budget and
allowed me to test all the intakes I had. Although he races RX7s, he was also a G35 owner so I think that helped. I’m very glad I got to meet Steve;
he is a very experienced tuner who had a lot of insight to offer during my testing. With Steve in the driver’s seat, I felt like the testing was taken
to a higher level than what I could have achieved on my own. He was really an asset to the testing.
After lining up a date for the dyno test, I prepared for testing. We made an event out of the day and many members of the DFW G Club got
together at his shop. While I wasn’t able to enjoy hanging out with everyone as much as I would have liked, I’m glad everyone who was able to see
the results. So not only did Steve and I have verification of the results, but around 12 other people showed up who can testify about the way the
testing was handled.
On October 30th the testing took place at Kan Tuning in Fort Worth, TX. We started around 12:30 and finished up after 6:00pm. Everything went
smoothly from what I could tell - there were no major issues to speak of. There were a few codes thrown when I forgot a vacuum hose before one run,
and another time when I put the MAF sensor in backwards. But I fixed the problems, cleared the codes with Cipher and continued testing. By the end of
the day I had ascertained a good bit of information of how various intakes affect performance of my engine. I was excited at all the data I had
gathered, and the power I had gained from the finding the best combination of intake parts for my engine.
I originally felt confident that I had finally discovered the best setup for my car at this point in my build. The problem was, the more I
looked at the data the more variables came up that I had no control over.
I had come to find that the full story of the intakes was not uncovered. No, I was just at the surface level of the story and the real
meaning of what was happening was still hidden from my understanding.
I’m sure by now you have probably stopped reading and are scrolling around looking for the dyno sheets to see which intake is the best.
That’s what this whole thing is about, right? Well I purposely formatted my report in this way, so that you try to understand the meaning of my
findings instead of taking the dyno numbers at face value. Just stay with me a little longer and I promise you’ll get to the data.
From what I can tell, system performance is HIGHLY dependent on the how the MAF is calibrated. When I put an aftermarket intake on it
caused the MAF to read more air coming in compared to the stock box. In Cipher there is a mass g/sec reading that comes from the MAF sensor. Most
aftermarket intakes caused this number to be higher than stock. Now the tricky part was to determine if the amount of air going in to the engine
was accurate based on the MAF, or if there was some other factor causing the MAF to read a higher amount of air than what was actually going into
the engine.
The only sign I had that the engine wasn’t getting as much air as the MAF was saying, was my Air to Fuel ratios. On some intakes my A/F Ratios
got very low (into the 10s). It seemed my engine was dumping fuel into the chamber and expecting a specific amount of air to be there (based on the
MAF signal) however with the low A/F Ratios I was seeing, I was led to believe it wasn’t actually getting the large amounts of air the MAF was saying
it was.
My theory for why this was happening stems from two possible sources:
First, for intakes that didn’t use the stock MAF housing, I think there was a MAF scaling issue. I’ve done research on NA builds and it is
known that with a 3” MAF housing and the appropriate tuning and calibration you can realize a HP gain of 5 – 10 HP depending on supporting mods.
Without tuning and calibration the ECU cannot adapt to a MAF housing that is a different size than the stock one. Whether larger or smaller, the
ECU will likely have issue with adapting to a MAF housing that isn’t the same size as the stock housing.
The second possibility has to do with air turbulence causing inaccurate MAF readings. I was able to prove a power loss on my setup when
doing a dyno run without the air filter. You would think that having less restriction would lead to gains, however the opposite occurred. This
is why I think the Stock panel filter or a K&N (in the stock air box) perform a specific smoothing effect on the air that the stock MAF is calibrated
for. With cone shaped filters attached to the intake tube, the air enters the tube at a different angle compared to stock. Being calibrated to read
air coming in to the tube one way, it is probably the case that the MAF is misreading the amount of air when using a cone type filter.
I think with tuning and calibration it’s possible to fix both of these issues in order to gain power.
I feel like the ECU, being designed to run and learn with the stock intake installed, probably learns faster with the stock intake compared
to when it had an aftermarket intake on. So, in the shorter learning periods in which they were tested (ie: not days of learning which would be
preferred), the stock box had the advantage over aftermarket. I think it’s possible that with more learning time, the car would adapt and possibly
make more power than the dyno plots showed.
Since I was paying for the dyno out of pocket, I wasn’t able to spend a whole day there, 6 hours already cost me around $500 - I simply could
not afford to spend more time. I tried to give each intake a fair chance, and there was a definite variation between each. It was immediately clear
on the dyno which intake was on. It wasn’t like the numbers were all over the place; they were quite consistent for each intake.
But to conclude this write up, from the data I have gathered, aftermarket intakes will need tuning at the very least to make power on my
vehicle. I think it’s slightly misleading that most intake manufacturers advertise gains with intakes, and I was not able to prove them. I would
love to have been able to tune each intake on my car to see its maximum potential, but I think the average person buying an intake will not factor
tuning in when they are purchasing an intake. They will likely expect power gains and probably be let down when they see this data.
Is there another factor that could account for these losses?
Just in the time of writing this I came up with a new theory of why intakes may have underperformed on my setup. I think it’s possible that
intake manufacturers know the cars run a bit lean from the factory and they engineer the intake to trick the MAF in order to add fuel. I’m positive
in this case it would put the AFRs to a level that would increase power over the stock setup. Now my engine was already tuned so on the stock box
the AFRs were around 12.8 where they should be; when we added intakes on my setup they got very rich. On a stock tuned VQ35DE the AFRs would be in
the high 13s and I think it’s possible that the intakes causing the AFR’s to drop into the high 12’s would show a power gain. Now this power gain
wouldn’t be anything the intake is actually doing to get more air in the car, but just improving on the stock AFR by tricking the ECU. So without
tuning it may be beneficial to add an intake to your setup. This doesn’t mean the Aftermarket is better or worse than the stock box by any means,
but it could be a viable way to add power with bolt-ons before a tune. Something I hadn’t considered until just now.
click here to see data
* For donations to cover Dyno Fee and further my intake testing, Please send as a gift in paypal to: Raider2043@hotmail.com *
THANK YOU FOR YOUR CONTRIBUTION:
ITNKICN - $100!!!
gword256 - $45!!
gabe3d - $25!
Ninja1 - $20!
obender66 - $10
SwivelHips - $10
NFSP G35 - $5
Last edited by sexyrob; 04-09-2013 at 11:52 PM.
#2
12-16-2010, 03:13 PM
Next was locating a dyno for testing. I had originally dynoed at Cobb tuning in Plano in a Z vs G dyno day back in December 2009, so I had
a baseline there. I emailed them first asking for pricing for my project. It was a bit high, but I was ready to forgo the expense to do the testing.
Luckily, G35driver member Duelper4mance suggested I contact Steve Kan of Kan Tuning. He was able to get me rates that better fit my budget and
allowed me to test all the intakes I had. Although he races RX7s, he was also a G35 owner so I think that helped. I’m very glad I got to meet Steve;
he is a very experienced tuner who had a lot of insight to offer during my testing. With Steve in the driver’s seat, I felt like the testing was taken
to a higher level than what I could have achieved on my own. He was really an asset to the testing.
After lining up a date for the dyno test, I prepared for testing. We made an event out of the day and many members of the DFW G Club got
together at his shop. While I wasn’t able to enjoy hanging out with everyone as much as I would have liked, I’m glad everyone who was able to see
the results. So not only did Steve and I have verification of the results, but around 12 other people showed up who can testify about the way the
testing was handled.
On October 30th the testing took place at Kan Tuning in Fort Worth, TX. We started around 12:30 and finished up after 6:00pm. Everything went
smoothly from what I could tell - there were no major issues to speak of. There were a few codes thrown when I forgot a vacuum hose before one run,
and another time when I put the MAF sensor in backwards. But I fixed the problems, cleared the codes with Cipher and continued testing. By the end of
the day I had ascertained a good bit of information of how various intakes affect performance of my engine. I was excited at all the data I had
gathered, and the power I had gained from the finding the best combination of intake parts for my engine.
I originally felt confident that I had finally discovered the best setup for my car at this point in my build. The problem was, the more I
looked at the data the more variables came up that I had no control over.
I had come to find that the full story of the intakes was not uncovered. No, I was just at the surface level of the story and the real
meaning of what was happening was still hidden from my understanding.
I’m sure by now you have probably stopped reading and are scrolling around looking for the dyno sheets to see which intake is the best.
That’s what this whole thing is about, right? Well I purposely formatted my report in this way, so that you try to understand the meaning of my
findings instead of taking the dyno numbers at face value. Just stay with me a little longer and I promise you’ll get to the data.
From what I can tell, system performance is HIGHLY dependent on the how the MAF is calibrated. When I put an aftermarket intake on it
caused the MAF to read more air coming in compared to the stock box. In Cipher there is a mass g/sec reading that comes from the MAF sensor. Most
aftermarket intakes caused this number to be higher than stock. Now the tricky part was to determine if the amount of air going in to the engine
was accurate based on the MAF, or if there was some other factor causing the MAF to read a higher amount of air than what was actually going into
the engine.
The only sign I had that the engine wasn’t getting as much air as the MAF was saying, was my Air to Fuel ratios. On some intakes my A/F Ratios
got very low (into the 10s). It seemed my engine was dumping fuel into the chamber and expecting a specific amount of air to be there (based on the
MAF signal) however with the low A/F Ratios I was seeing, I was led to believe it wasn’t actually getting the large amounts of air the MAF was saying
it was.
My theory for why this was happening stems from two possible sources:
First, for intakes that didn’t use the stock MAF housing, I think there was a MAF scaling issue. I’ve done research on NA builds and it is
known that with a 3” MAF housing and the appropriate tuning and calibration you can realize a HP gain of 5 – 10 HP depending on supporting mods.
Without tuning and calibration the ECU cannot adapt to a MAF housing that is a different size than the stock one. Whether larger or smaller, the
ECU will likely have issue with adapting to a MAF housing that isn’t the same size as the stock housing.
The second possibility has to do with air turbulence causing inaccurate MAF readings. I was able to prove a power loss on my setup when
doing a dyno run without the air filter. You would think that having less restriction would lead to gains, however the opposite occurred. This
is why I think the Stock panel filter or a K&N (in the stock air box) perform a specific smoothing effect on the air that the stock MAF is calibrated
for. With cone shaped filters attached to the intake tube, the air enters the tube at a different angle compared to stock. Being calibrated to read
air coming in to the tube one way, it is probably the case that the MAF is misreading the amount of air when using a cone type filter.
I think with tuning and calibration it’s possible to fix both of these issues in order to gain power.
I feel like the ECU, being designed to run and learn with the stock intake installed, probably learns faster with the stock intake compared
to when it had an aftermarket intake on. So, in the shorter learning periods in which they were tested (ie: not days of learning which would be
preferred), the stock box had the advantage over aftermarket. I think it’s possible that with more learning time, the car would adapt and possibly
make more power than the dyno plots showed.
Since I was paying for the dyno out of pocket, I wasn’t able to spend a whole day there, 6 hours already cost me around $500 - I simply could
not afford to spend more time. I tried to give each intake a fair chance, and there was a definite variation between each. It was immediately clear
on the dyno which intake was on. It wasn’t like the numbers were all over the place; they were quite consistent for each intake.
But to conclude this write up, from the data I have gathered, aftermarket intakes will need tuning at the very least to make power on my
vehicle. I think it’s slightly misleading that most intake manufacturers advertise gains with intakes, and I was not able to prove them. I would
love to have been able to tune each intake on my car to see its maximum potential, but I think the average person buying an intake will not factor
tuning in when they are purchasing an intake. They will likely expect power gains and probably be let down when they see this data.
Is there another factor that could account for these losses?
Just in the time of writing this I came up with a new theory of why intakes may have underperformed on my setup. I think it’s possible that
intake manufacturers know the cars run a bit lean from the factory and they engineer the intake to trick the MAF in order to add fuel. I’m positive
in this case it would put the AFRs to a level that would increase power over the stock setup. Now my engine was already tuned so on the stock box
the AFRs were around 12.8 where they should be; when we added intakes on my setup they got very rich. On a stock tuned VQ35DE the AFRs would be in
the high 13s and I think it’s possible that the intakes causing the AFR’s to drop into the high 12’s would show a power gain. Now this power gain
wouldn’t be anything the intake is actually doing to get more air in the car, but just improving on the stock AFR by tricking the ECU. So without
tuning it may be beneficial to add an intake to your setup. This doesn’t mean the Aftermarket is better or worse than the stock box by any means,
but it could be a viable way to add power with bolt-ons before a tune. Something I hadn’t considered until just now.
click here to see data
* For donations to cover Dyno Fee and further my intake testing, Please send as a gift in paypal to: Raider2043@hotmail.com *
THANK YOU FOR YOUR CONTRIBUTION:
ITNKICN - $100!!!
gword256 - $45!!
gabe3d - $25!
Ninja1 - $20!
obender66 - $10
SwivelHips - $10
NFSP G35 - $5
a baseline there. I emailed them first asking for pricing for my project. It was a bit high, but I was ready to forgo the expense to do the testing.
Luckily, G35driver member Duelper4mance suggested I contact Steve Kan of Kan Tuning. He was able to get me rates that better fit my budget and
allowed me to test all the intakes I had. Although he races RX7s, he was also a G35 owner so I think that helped. I’m very glad I got to meet Steve;
he is a very experienced tuner who had a lot of insight to offer during my testing. With Steve in the driver’s seat, I felt like the testing was taken
to a higher level than what I could have achieved on my own. He was really an asset to the testing.
After lining up a date for the dyno test, I prepared for testing. We made an event out of the day and many members of the DFW G Club got
together at his shop. While I wasn’t able to enjoy hanging out with everyone as much as I would have liked, I’m glad everyone who was able to see
the results. So not only did Steve and I have verification of the results, but around 12 other people showed up who can testify about the way the
testing was handled.
On October 30th the testing took place at Kan Tuning in Fort Worth, TX. We started around 12:30 and finished up after 6:00pm. Everything went
smoothly from what I could tell - there were no major issues to speak of. There were a few codes thrown when I forgot a vacuum hose before one run,
and another time when I put the MAF sensor in backwards. But I fixed the problems, cleared the codes with Cipher and continued testing. By the end of
the day I had ascertained a good bit of information of how various intakes affect performance of my engine. I was excited at all the data I had
gathered, and the power I had gained from the finding the best combination of intake parts for my engine.
I originally felt confident that I had finally discovered the best setup for my car at this point in my build. The problem was, the more I
looked at the data the more variables came up that I had no control over.
I had come to find that the full story of the intakes was not uncovered. No, I was just at the surface level of the story and the real
meaning of what was happening was still hidden from my understanding.
I’m sure by now you have probably stopped reading and are scrolling around looking for the dyno sheets to see which intake is the best.
That’s what this whole thing is about, right? Well I purposely formatted my report in this way, so that you try to understand the meaning of my
findings instead of taking the dyno numbers at face value. Just stay with me a little longer and I promise you’ll get to the data.
From what I can tell, system performance is HIGHLY dependent on the how the MAF is calibrated. When I put an aftermarket intake on it
caused the MAF to read more air coming in compared to the stock box. In Cipher there is a mass g/sec reading that comes from the MAF sensor. Most
aftermarket intakes caused this number to be higher than stock. Now the tricky part was to determine if the amount of air going in to the engine
was accurate based on the MAF, or if there was some other factor causing the MAF to read a higher amount of air than what was actually going into
the engine.
The only sign I had that the engine wasn’t getting as much air as the MAF was saying, was my Air to Fuel ratios. On some intakes my A/F Ratios
got very low (into the 10s). It seemed my engine was dumping fuel into the chamber and expecting a specific amount of air to be there (based on the
MAF signal) however with the low A/F Ratios I was seeing, I was led to believe it wasn’t actually getting the large amounts of air the MAF was saying
it was.
My theory for why this was happening stems from two possible sources:
First, for intakes that didn’t use the stock MAF housing, I think there was a MAF scaling issue. I’ve done research on NA builds and it is
known that with a 3” MAF housing and the appropriate tuning and calibration you can realize a HP gain of 5 – 10 HP depending on supporting mods.
Without tuning and calibration the ECU cannot adapt to a MAF housing that is a different size than the stock one. Whether larger or smaller, the
ECU will likely have issue with adapting to a MAF housing that isn’t the same size as the stock housing.
The second possibility has to do with air turbulence causing inaccurate MAF readings. I was able to prove a power loss on my setup when
doing a dyno run without the air filter. You would think that having less restriction would lead to gains, however the opposite occurred. This
is why I think the Stock panel filter or a K&N (in the stock air box) perform a specific smoothing effect on the air that the stock MAF is calibrated
for. With cone shaped filters attached to the intake tube, the air enters the tube at a different angle compared to stock. Being calibrated to read
air coming in to the tube one way, it is probably the case that the MAF is misreading the amount of air when using a cone type filter.
I think with tuning and calibration it’s possible to fix both of these issues in order to gain power.
I feel like the ECU, being designed to run and learn with the stock intake installed, probably learns faster with the stock intake compared
to when it had an aftermarket intake on. So, in the shorter learning periods in which they were tested (ie: not days of learning which would be
preferred), the stock box had the advantage over aftermarket. I think it’s possible that with more learning time, the car would adapt and possibly
make more power than the dyno plots showed.
Since I was paying for the dyno out of pocket, I wasn’t able to spend a whole day there, 6 hours already cost me around $500 - I simply could
not afford to spend more time. I tried to give each intake a fair chance, and there was a definite variation between each. It was immediately clear
on the dyno which intake was on. It wasn’t like the numbers were all over the place; they were quite consistent for each intake.
But to conclude this write up, from the data I have gathered, aftermarket intakes will need tuning at the very least to make power on my
vehicle. I think it’s slightly misleading that most intake manufacturers advertise gains with intakes, and I was not able to prove them. I would
love to have been able to tune each intake on my car to see its maximum potential, but I think the average person buying an intake will not factor
tuning in when they are purchasing an intake. They will likely expect power gains and probably be let down when they see this data.
Is there another factor that could account for these losses?
Just in the time of writing this I came up with a new theory of why intakes may have underperformed on my setup. I think it’s possible that
intake manufacturers know the cars run a bit lean from the factory and they engineer the intake to trick the MAF in order to add fuel. I’m positive
in this case it would put the AFRs to a level that would increase power over the stock setup. Now my engine was already tuned so on the stock box
the AFRs were around 12.8 where they should be; when we added intakes on my setup they got very rich. On a stock tuned VQ35DE the AFRs would be in
the high 13s and I think it’s possible that the intakes causing the AFR’s to drop into the high 12’s would show a power gain. Now this power gain
wouldn’t be anything the intake is actually doing to get more air in the car, but just improving on the stock AFR by tricking the ECU. So without
tuning it may be beneficial to add an intake to your setup. This doesn’t mean the Aftermarket is better or worse than the stock box by any means,
but it could be a viable way to add power with bolt-ons before a tune. Something I hadn’t considered until just now.
click here to see data
* For donations to cover Dyno Fee and further my intake testing, Please send as a gift in paypal to: Raider2043@hotmail.com *
THANK YOU FOR YOUR CONTRIBUTION:
ITNKICN - $100!!!
gword256 - $45!!
gabe3d - $25!
Ninja1 - $20!
obender66 - $10
SwivelHips - $10
NFSP G35 - $5
Last edited by sexyrob; 04-09-2013 at 11:52 PM.
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#6
12-16-2010, 03:28 PM
#7
12-16-2010, 03:28 PM
Trending Topics
#8
12-16-2010, 03:29 PM
#9
12-16-2010, 03:31 PM
that pictured filter is the JWT Pop Charger that is sprayed with K&N spray. It was all on the same table together..our OEM airbox's dont take a cone unless some parts are removed. I think that the NO Filter means not aftermarket..OEM
#10
12-16-2010, 03:35 PM
#11
12-16-2010, 03:35 PM
#12
12-16-2010, 03:37 PM
your good man! def not defensive! just clarifying what the pictures consist of for those reading all post so they know.
#14
12-16-2010, 03:43 PM
Thanks for the info, I'll take a better look at the results on my home desktop.
But why would you rule out heat soak when that's one of the main downfall's of aftermarket intakes? I also wish dyno's were done with the hood closed to simulate "real world" driving since people don't drive around with their hoods open and have that extra air going to their SRI's.
But why would you rule out heat soak when that's one of the main downfall's of aftermarket intakes? I also wish dyno's were done with the hood closed to simulate "real world" driving since people don't drive around with their hoods open and have that extra air going to their SRI's.
