So i got a few parts installed yesterday, including a Motordyne 5/16 Copper Plenum spacer, HR Y-Pipe, Coupe Midpipe, HKS Muffler and a 06 Revup airbox with a K&N drop in.
First, i don't feel any power difference with the mods. I don't know if its because i had high expectations, but i don't feel it as much as my friends 04 coupe, which is also an AT and only has a spacer.
Second, the exhaust note is very nice, but not as loud as i expected. It is the loudest and best sounding on start-up and then after that it gets a quiet until about 4500 rpm.
Third, there is a very annoying squeaking noise coming from the intake when i hit the gas. Its not the whooshing noise that everyone else talks about, its a high pitched squeak.
Fourth, my radiator leaks a lot after the install and didn't before. There are large puddles under my car after 5 minutes of it being parked.

Any help me with any of these things would be appreciated. Thanks a lot

 

1. you did a lot in a short time so to get the most out of your efforts you need a proper tune & ECU reset. you will not see massive gains from these mods so don't expect a total transformation, but you should notice a little extra grunt (~10-15whp) - from what i've read on here.
2. the exhaust is what it is. give it some time and you'll like it more and more - i know i did. we aren't driving civics with loud fart-can mufflers so keep that in mind.
3. don't know about squeak. maybe just an induction whistle? check to see if you have any leaks or loose connections.
4. this should be unrelated. you normally don't need to mess with the radiator for these mods. check your hoses & connections and fix it.

 

HKS muffler and coupe MP will maybe give you like 4 whp. very minimal. The spacer should give you around 10 whp. HR y-pipe is negligible. Rev-up airbox is neglibigle. You'll gain more from an intake.

I been through the rounds with all the stuff you have.

If you want to make the exhuast a little louder go get some HFC. It will give you more grunt and some actual power. If you really want more power and grunt get the Motordyne xyz and the y-back (VQ) and some HFC. Much better power, better exhaust sound as well.

 

Radiator leaking is a problem. Find the leak, fix the leak. If its the radiator, buy a new one.

 

Did you reset ECU?

 

Havent reset the ecu yet... idk whether to do it the way it is described on the forum with the pedal hits and everything or to just unplug the battery over night. I am also going to have my dealer advance the ignition timing 2 degrees and see if that helps. The only real thing i was wondering about was the whistle from the intake because its really annoying and takes a lot away from the exhaust sound. Thanks for the replys.

 

HR Y-pipe makes the same power as the XYZ pipe and without the low rpm power loss.

 

Check your work. Take off the intake and reinstall it. Verify all the gaskets are in place and things are properly tightened. Same goes for the spacer. Check your work. Also, you need to give the car a little time to learn everything that's been done. It make take about 100 miles or so. Each day you should notice the car feeling a little stronger.

As for the rad leak, you're going to have to get under the car and start looking around. The problem seems underrrelated unless you disconnected the coolant line going to the throttle body.

 

I installed the z tube and pop charger, at first the car seemed very sluggish. I got it home unplugged the negative battery terminal over night. When I drove it the next morning it was completely different, it was very peppy. Definitely reset the ecu with battery terminal. I tried the foot pedal reset and the CEL light never came on.

 

Are you kidding?? LOL. Not true. Not by a long shot. I've had both.

 

No, I'm not kidding.

HR Y-pipe (Dynojet)

https://g35driver.com/forums/tuner-d...pipe-dyno.html




XYZ Pipe (Dynapack)

http://my350z.com/forum/intake-exhau...-bolt-ons.html

Keep in mind the Dynapack will show higher numbers than the Dynojet.

 

^^^ explain the graph... are you saying red in HR Y pipe and blue is XYZ?...

Edit - that graph doesnt mean anything anyway = those runs were done a year apart...

I dont know what you are showing Dave... explain...

 

What I'm showing dyno plots of the HR y-pipe making the same gains as the XYZ pipe. Yes, the dynos are one year a part, but the runs were on the same machine and same conditions. The changes in the power curve are clearly apparent. If it were a dyno fluke, the changes would be across the whole curve. There's definitely an improvement from 4500rpms and up. The power below 4500 is spot on with the last graph.

 

Again, I’ll ask… does that graph represent HR Y pipe and XYZ?… if so I presume red is HR Y pipe and blue is XYZ… nothing on the graph indicates what it is… also, I do not concur with your conclusions about dyno testing… no one that conducts controlled tests would use dynos that are a year apart (for any reason).

Anything other than back-to-back dyno’s with both exhausts are inconclusive imo.

 

i think he's just showing gains over stock for each and comparing... measuring gains over stock on separate occasions makes sense, as long as both cars where stock w/same options.