Dynojets typically read 10% higher than our Dynapack, so your 242WHP matches the 220WHP we found with our Revup almost perfectly. A non revup (287 vs about 300hp) will show about 10-12whp lower on a dyno. So our non-revup G35 showing 205-206whp is not unreasonable (14-15whp below our revup).

We have documented results of longtubes making 30whp BACK TO BACK on our 2006 roadster, and our updated larger diameter longtubes making another 13whp on those headers. The link is attached below:

Roadster 30whp with coast fab longtubes from our Grand-Am Cup Racecar:

http://my350z.com/forum/na-builds/39...-roadster.html

Racecar 13whp Over Coast Fab Longtubes:

http://my350z.com/forum/6770290-post85.html

When you switch from a revup plenum to an MREV you are obviously going to lose peak power, so your compromise for midrange power is one of the reasons you haven't gained more HP. I agree that this is the right thing to do for 99% of street cars, but when we're talking about dyno figures, you have to take into account that is why your power is only up 25whp.

We have back to back tested almost every bolt on for the G, I can post more results if you would like of a revup we did that baselined at 220whp, and got a Stillen pop-charger, Stillen true dual, Motordyne spacer, Stillen headers, Stillen high-flows - ALL parts installed and then tested on the dyno, run after run after run. The headers and test pipes were installed on a second occasion, but we baselined that day to verify the power matched the previous session.

Trey, I'll tell YOU what, you want to test some parts - I would be more than happy to send them down to you, have you baseline your car and install whatever parts you want, and re-dyno on the same day. I will gladly refund your money if you do not make at least 80% of the gains we've seen here.

What we are doing is making 250-260whp out of a 3.5L engine that has the same technology and efficiency of a Honda or any other engine that has proven to be able to make 100HP per litre. We are not saying we are making 800hp here, it is just simply that the VQ's are bottle necked from the factory. Certain bolt-on mods done correctly can have these motors producing 280-290whp, it has been done a million times in Japan, Europe and even North America if you open your eyes. Making N/A power is not impossible!! Please watch the longtube video to get an idea of how serious we are about this stuff - we are not simply bolting on parts and hoping they make power.

Thanks for reading.

 

I want to know if that Z still has the same licence plate and how they got it past the DMV.

 

subscribing....

 

me too

for n/a power
keep up the vq work SG motorsports.
350z in video sounds mean!!!

 

I'm not disputing absolute numbers - I don't care if its 220, 240, 260, or what. The fact is that on my local dynojet, I picked up less than 25whp and right at 50wtq with all the mods and the tune. I don't care if the dynapack is "10% lower" than a dynojet - those gains are still unreasonable.

I'm gonna catch flack for this(and to be honest, I would nail somebody else for doing what I'm about to do), but I have not researched your product nor have I followed your links. I'll admit that its not intellectually honest to dispute your claims without being educated on the details of your claims. The fact is that this is the first time I've been back in the "scene" for months, and I just don't have the time to stay up-to-date as I once did.

Regardless of all that, longtubes, especially *larger diameter* longtubes, are not going to produce 35whp on this platform. There's simply not enough volume of air being moved, or more importantly, *not being moved*, with the stock cats and stock manifolds, to see that kind of increase.

I didn't want to go into all of the details of my intake configuration, but here they are: I've run the stock airbox, the stock airbox plus a panel filter, a spacer, a machined 03/04 lower plenum, the stock lower plenum, and some combination of each of these parts. In fact, the mrev lower plenum I have now isn't exactly an "mrev." I bought the spacer from Tony, and I had already sourced an OEM lower plenum, and I sent it to him to machine. He was kind enough to machine it and return it to me. After he released the mrev2, I asked him if it would be worth it for me to upgrade to the newer lower plenum. He responded that the machining applied to my collector was more than half-way between the mrev+ and the mrev2, so I would see negligible, if any gains. I have since removed the plenum.

And I don't get your statement that the mrev would cost me peak HP. That doesn't make sense. Granted, the mrev changes the profile of the powerband, but it does in fact show gains in peak power. Now, *after peak*, it loses power on its way to redline, compared to the stock profile where nearly peak power is maintained to redline(on the revup).

If you think that I'm some random dude coming out just to take you on, then you're wrong. It really wasn't my intent to come in here and poo-poo your products or your company, but I do think that your claimed gains are unrealistic. I've simply spent too much time, labor, and money, on my car to ever believe gains like that.

If you look back at my post history, you will find the following [relevant] threads that I have started:
Disappointed; car's lost power
Dyno numbers - stock vs stillen airbox, stock vs mrev
Dyno Day: 05 6MT(Revup) Full Bolt-ons vs stock 07 6MT HR - Videos
3.5 HR may take well to exhaust mods
1st place at dyno day for all motor
Final numbers are in: revup+bolt ons+utec
Dynod for a new baseline of the new longblock
Dyno: test pipes and spark plugs
Clutchmasters Stage1 + JWT Flywheel
Another dyno(crawfords cats+stillen intake)
MREV and Stillen 1st Gen installed
04/05 Muffler Analysis(multipart)

On top of all that, I'm an avid drag racer. At present, I hold the #1 time here on driver in the 1/4 in the all-motor category, and the #10 overall time on my350z in the all-motor category.

 

I side with Trey and all his points. All the mods posted are not ground breaking and dynos for all these parts in all combinations are plentiful. Most of us G diehards know that an intake doesn't do anything on these cars, the MD spacer is good for 7whp to 8whp, a catback is worth 5whp to 8whp, and tuning on a car with the typical bolt-ons is worth 5whp to 10whp. These numbers just aren't making sense.

A few things I'd like to point out. I've never dynoed my car, but I've dynoed other VQs I've owned and I've watched many a VQ30 and VQ35 get dynoed. Something I've noticed, especially with the VQ35s, is that they tend to get stronger after each successive dyno. It's has if the ECU is slightly confused at first when the rear tires are traveling faster than the fronts and power is killed. After each dyno, the ECU becomes more accepting. It's not uncommon to see a 10whp between the first dyno and the 3rd or 4th.

Secondly, since this is a Dynapack you can adjust load which then could affect power. Not saying these guys are doing it, but you could manipulate the power numbers by varying the drum brake. Dynapacks and other brake dynos are ideal tuning dynos because you can apply heavy load.

Finally, I'll really interesting in seeing some picks of these longtubes. I highly doubt they make 30whp like they do on the LSX, but I'm sure they could make a legit 15whp-20whp. Longtudes are where it's at when it comes to making power and fattening up the powerband.

 

subscribed


i really wanna know where this goes

 

Look at the very first of the vid (0.06 sec), they are in there.

 

your tuner's conversions for the dyno are way off. A stock G35 should dyno around 220 whp. This doesn't say a lot about tuners that use the osiris......

 

Yeah, I opened my mouth without watching the video first. The headers looks pretty sweet and are truely longtubes. My biggest concern would be underhood heat. In the video, those bad boys start glowing red. I'll also point out that these guys made the LTs pretty simple and it's always shocked me that other vendors that make headers didn't figure this out years ago. Making LTs is simple because all these company's needed to do was instead of joining their header at a flange to connect to the cat, they should have tossed the cat and then kept the three pipes going down to the y-pipe flange. When you toss the cat, you have plenty of room for the three primary tubes. Then you make you're own y-pipe and make an option for a catless y-pipe and one with a big cat at the end of the y-pipe and lengthen the 02 sensor harnesses. It's so simple yet no one did it. This shop is really on to something.

 

Yeah, I think so too. The headers could be wrapped with heat tape to keep the heat down. But it sure would look ugly under the car. I just love the sound.

 

Underhood temps are always a concern, however when a vehicle is in motion the heat escapes extremely quickly, and even on the dyno with unwrapped, uncoated headers, the intake temps are just above ambient.

I have raced with these coast fab headers with a factory hood (no venting) and simply a small opening for the radiator, and it quite simply is not a problem. My Intake temps are never more than 4 degrees over ambient (My filter is in front of the radiator however).

I also have found the G's and Z's to pick up power after each run, and we have accounted for this accordingly. We do 7-8 pulls with each modification until the HP stops increasing and we see a pull with less power. We then let it sit for 7-8 min and do one final pull. That is always the highest HP pull and is always within 1.5hp. This G was dyno'ing in the 190s when we first brought it to the dyno. I'm not sure if it is the ECU or if it is the Tranny and Diff warming up or what, but the gains we see do diminish the hotter the drivetrain gets.

I'm not sure why no one is finding gains with an intake, perhaps there hasn't been enough testing on it. But the two intakes we've built are simple 3" intakes using a BPI flow stack and we've always seen great gains with them. The BPI flowstack may be a large part of that.

Trey,

I'm really sorry you've had a hard time gaining HP with your VQ, but your tough experiences is not the be-all end-all of the VQ. I can see your frustration is bringing you to be doubtfull of other components, which is understandable. But one point I do want to make is that the MREV2 will LOWER the peak HP compared to a revup plenum. So if you do intake, exhaust, spacer, and make 240whp, then you add an MREV2, your power will become say 235whp, but you'll have more TQ where it counts.

The point i'm trying to get across is that the reason your gains are small (HP wise) is because you've switched your collector to one designed more for midrange power (which is the same plenum we use, because it has more usable power).

Finally, longtubes do make the power they make, quite simply, because the stock exhaust manifolds are not efficient, and that is one of the reasons we are experiencing a 3.5L engine only producing 205-220whp stock. Nissan is NOT stupid. They know how to build a manifold that makes power. They simply do not because they want the cats AS CLOSE to the heads as possible, for the fastest warm up and least start up emissions possible. A properly designed longtube is one of the many tuning methods you can use to get VE ABOVE 100%, so you cannot simply put a statement down like:

"Regardless of all that, longtubes, especially *larger diameter* longtubes, are not going to produce 35whp on this platform. There's simply not enough volume of air being moved, or more importantly, *not being moved*, with the stock cats and stock manifolds, to see that kind of increase. "

We are talking about more than simple flow restrictions here, proper longtubes make power because they organize the pulses of each cylinder and allow them to literally tug on one another, sucking air out of cylinders. So you're going from a huge restriction to acoustic supercharging. THAT is why they make the power they do. Larger diameters will simply make the power up top, where smaller ones will make the power down low.

To make best example of this, If I ran my car on the dyno open header, with no collectors and no exhaust, it would make significantly LESS power then when connected to the collectors and tuned y-pipe.

 

Why are you always hating on Osiris? Have you ever used it? I always hear you b*tching about it but you NEVER back up your argument.

If his numbers are inflated then you can pin that on the dyno before you can ever pin that on Osiris.

 

lol, love this thread already

 

subbed.