First of all, grats on getting married Tony! If you decide to come down to Dubai for your honey moon lemme know lol

The issue is clearly a cam issue and the headers have nothing no to do with it.. putting back restrictive cats to get more hp simply doesn't make sense.

Thanks for the congrats on the marriage. On the other issue, it is not the cams. It is the supercharger kit. Do not get me wrong, unlocking the tuning to advance the timing of the cams will net higher numbers for sure. However, if it was the cams the headers would have the same effect N/A. In fact, it is the complete opposite N/A. GTM is claiming that the car needs the back pressure to make the numbers. However, back pressure is mainly related to torque not power. So explain to me when relieving the back pressure N/A how we picked up more torque than anything else!

Tony

Re Post so everyone can see this on the most current page!

A must read for all long tube header owners thinking of adding the GTM supercharger kit:

I wanted to chime in real bad on the GTM supercharger thread. But I have bit my tongue and out of respect for Sam and GTM I will do this in my own thread.

There is alot of talk going around that my headers "flow too well" for the HR motor due to the VVEL with the long duration and overlap.

Shumby now is a proud owner of the GTM supercharger kit for his G37 and has removed our headers due to a lack of boost and power with them. I cannot sit here for any longer and let my headers take the abuse for something else that is causing the issue. I feel that it is not a tuning issue. I feel that it is a hardware issue, i.e. the supercharger itself or the kit.

Here is the deal, headers relieve back pressure. By relieving back pressure you will have a PSI drop off (boost). The goal should be to make as a much torque and power on as little boost as possible. This is called "efficiency".

I have never in my life ever, ever, ever, installed a supercharger on a car along with headers and lost power. The only way it is possible is if the supercharger kit is inefficient. This leads me into the next phase of the topic.

I have spoke to Shumby myself over the phone and here is the information I was given:

Tony, we supercharged the car and with the headers installed along with your exhaust it only made 4 psi. Then we put a smaller pulley on it and only picked up 15 horsepower and very little boost. I was never given the boost number I might add and I don't think Shumby was either. Then I was told the headers were removed and stock manifolds along with stock cats were installed. I was told at this point the car made 6-1/2 psi. So then they took the stock cats back off and put the GTM straight test pipes on the car. Same result, the psi dropped back to a very close place to the headers. No doubt, the stock cats are much more restrictive than the long tube headers or even straight test pipes. So now the stock cats were put back on the car and oh but wait, a boost leak was found. But I was told it was minimal. Either way it is force induction and a leak is detrimental to boost and power! So naturally I asked, after the leak was rectified did you put the headers back on the car a dyno it again. The answer was no we did not!

I want to see an 8 psi stock cat, stock manifold number vs. FI long tube header 8 psi number. I would bet the farm that apples compared to apples we would make higher number across the board. If you cannot get the boost back up with the long tube headers than the supercharger itself cannot move enough volume AKA (CFM) or the supercharger kit itself is holding it back. Size of intercooler, tubing size, the way tubing is routed. A good way to see if the intercooler is efficient is to take a psi reading before it as well as after it. If the psi drop off is dramatic after it than the intercooler is not efficient. If the intercooler is efficient than it is most likely the head unit itself. It physically is just too small and cannot support enough volume to feed to motor. Bottom line you then rely on the stock cats to build the boost.

Here is where the problem lyes with that. Boost is heat and the stock cats were never intended to have #1 to have that much velocity forced through them, (especially for extended periods of time). #2 being a ceramic cat they will never hold up to that kind of abuse. Worst case scenario you send the EGT's (exhaust gas temperature) through the roof before the cat and melt it shut. I think it is a poor selling point to tell people, here is my supercharger kit please buy it. Oh by the way you need to keep stock manifolds and stock cats on the car the make the boost and in return make numbers!

If the car needed that much back pressure than explain why naturally aspirated with no air being crammed into the motor how we picked up substantial amounts of torque and also power accross the board! So until I see see an independent dyno done correctly comparing apples to apples than I am not buying the information that is being sold.

This will also be posted on the first page of this headers thread.

Thank you for taking the time to read this. The phone lines are open...

Tony

Tony :bowdown:

Tony, I have Stillen headers and High Flow cats and my boost was exactly what it was supposed to be with the Stillen Supercharger....8psi. Don't mean to start ****, but it's pertinent information.

right, that is exactly what he would expect. I think he is suggesting that there is something wrong with GTM's kit that is causing it to lose boost with low backpressure where is it seems the Stillen kit is holding just fine with headers and HFC's.

Oh jesus

Tony I'm glad you come out and addressed this issue, this was huge for me as well when I first heard about it. Your point about the stock cats is key, no one wants to destroy their cats and have to replace them regularly.

so..what about the stillen superchager? works fine with that?

you need custom tune my friend

don't they pretty much use the same stuff so I think it would be the same situation

The GTM uses a Rotrex SC where the Stillen uses a Vortech V3. The rotrex is technology is relatively new compared to standard centrifugal superchargers.

Little off topic Tony, but do you know which Rotrex unit he is using on the car? C38-61, C38-71, or the C38-81? Also what was his target hp?


I too find it hard to believe that headers can be the cause of this issue...

Good to hear :tup:

While I think GTM has a better layout of their s/c kit hardware this is a glaring issue. Tony is on point mentioning that the increase in heat will destroy the stock exhaust hardware. I remember hearing the same from AAM when I asked them if keeping the stock cats and exhaust would be an option, they stated that over time it would be turned into slag=an expensive fix.

Is there no concern over the fact that if your EGT's are hot enough to melt exhuast hardware it could do the same for your pistons?
Maybe some one with a TT or SC kit should hook up an EGT probe, I think it would be as beneficial as a WBo2 especially in tuning these FI setups. I am a great believer in data.



I would love a set of these headers, the only thing that stopped me is that I want to go TT.
These headers should reduce EGT's with the scavenging benefits, with a probe in there you could really balance the timing and fuel perfectly.
From what I can see on here FI make great stuff, +1 for putting it on the table

Tony if you have time please reply to my PM

Waiting on a reply as well....

:bowdown:

It's nice to see your defense for the "lack of backpressure" issue. That's a crap excuss and what's worse is that people were believing it without question.

I appreciate the support. I feel that people that do not know one way or the other can be easily persuded. But when I see the wrong information being put out there I have to step in and set the record straight. What makes it worse is when it is being said by a reputable shop. When you design a product and post results you have to be as honest as possible. If you lie or hide things the facts it will eventually make it's way out. Now I am not saying GTM is doing this on purpose. There was a boost leak and the head unit may just be too small. This was done on there entry level stage one kit. On top of that my headers didn't exist when there R&D started on the kit. However it is not like no one will ever do an independent dyno. As soon as I can, I will get my hands on a car with a Stillen kit and show what our headers can
do. That V3 head unit they use is a quality part. As long as the air to water intercooler is efficent things will work out in the positive column.

Tony, just tried to call you but I think my phone was freaking out. Give me a call on my cell.

Just tried giving you and it went straight to voicemail. I am on the road but you have my cell number. Call me when you have time.

It is my phone, all Tony's calls were going to my voicemall, I have zero missed calls today. No idea what is wrong.

iPhone?

Droid

Err, my iPhone does that alot at home (where I barely get signal) I'll get a voicemail, but never have a missed call... :wtf:

oagreed 100% and more people will soon find out as kits are being done.

Tony, I just watched the vid at the beginning of the thread again... :drool:

With that having the 12" Res, were they SS or CF?

Do you happen to have a vid of 18" Res either SS or CF?

Just trying to understand the different notes before locking in for one.

damn you're needy :gtfo2:


:rofl2:

If you don't have anything nice to contribute :gtfo2:

You don't even HAVE F.I. Exhaust m0fo! :bowrofl:

I would love to see a comparison of a car with the Stillen kit tuned with stock headers and cats vs LTH's with a retune.

Sadly, I think you really have to do this in order to clear your name. People believe what they read and right now there is a lot being written that LTH's will not work with a supercharger even though Tony said they would. Nevermind the fact that superchargers have worked better with less restrictive exhausts for the past century, now things have magically changed for the VQ37VHR. I think that getting your hands on a well tuned supercharged 3.7L and doing a back to back study of restrictive vs unrestrictive exhaust would force the others to answer some questions. I would leave the cat-back the same in order to eliminate variables and tune each combo for their best performance. And it looks like you would have to use a Stillen kit as it looks like this is the only supercharger that is out right now that can push enough air.

To be honest with everyone else, I have no intention of buying LTH's. I have a set of hfc's and a set of Stillen headers in the basement that I believe would work real well for me. I got both the headers and the hfc's used and cheap. My reason for posting is because someone is putting out bad information about a supercharger needing backpressure in order to run efficiently. That is simply not true.

yIt is sad and true. You better be careful. Some people will chop your nuts off if you say anything bad about GTM not that it matters and most of those people are not that bright when talking about the mechanics of cars. Some people have buy into Bull**** when they dont understand and they are having issues with there setup.

i will stay tuned for the stillen supercharger lth combo

I agree, however I admittingly was one of those who were big GTM S/C supporters. I have my LTH's at home and looking them over I can't say they look anything short of brilliant. The N/A installs also back up everything that Tony is saying and I'm sure it'll change the sound of my stock exhaust (test pipes on right now).

I guess we'll have to give it some more time and let the tuners figure out what they are doing but one thing is very clear, you cannot expect to keep on oem headers and cats with a power adder and keep it reliable in the long run.

last update was on the 17th , please assist us in this departement :)

:iagree:

Headin' down to float the Guadalupe this weekend so I will be out of pocket if you attempt to contact me Tony. I'll be leaving the Dallas area around 2p and I'm guessing I'll start missing phone calls about 6p or so.

I'm good for paying for my headers, I'll just pick a card to put them on :facepalm:

Oh, and another thing... CERAMIC COATED :excited:

An updated list will go up today!

UPDATE- 6/17/2010

HNGonzalez: 001 (Installed)
Semtex: 002 (Installed)
Daishi: 003 (Installed)
Mr. Anonymous: 004 (Delivered)
Kolya: 005 (Installed)
The Dreamer: 006 (Installed)
LeonZ5: 007 (Delivered)
Earwicker7: 008 (Installed)
Zello370: 009 (Delivered)
Matrix_Square: 010 (Delivered)
Dainedazz: 011 (Delivered)
Cotizi: 012 (Installed))
Jason S. (Delivered)
NYBladeZ: 014 (Delivered)
Valentino: 015 (Delivered)
res0zsfa: 016 CANNOT GET AHOLD OF YOU FOR PAYMENT (SKIP)
Danny3.7: 017 (Delivered)
Tardcore: 018 (Installed)
Booger: 019 (Installed)
PG6speed: 020 (In transit)
Jnaut: 021 (In transit)
Shultea1: 022 (Building)
VH370ZNISMO: 023 (Building)
Vipor: 024 (Building & will hipefully make it to the coaters before I depart)
E.Johnson: 025 (Delivered)
Jamaica951: 026
MattKim85: 027
Bejan: 028
roplusbee: 029
Vegitto-Kun: 030

On a side note, I am getting married on July 3rd and I will be out of the office from starting July 2nd and will not be returning until July 12th. MY GOAL is to have the entire group buy completed and shipped before I leave. That is sets #1-25! That leaves 3 more sets within the next week. I will try to make it happen. I know that this has taken longer than most have expected, myself included. Let's remember though production started a month late due to the tooling being almost a month late. In addition we have discovered that production on these is a little more time consuming than originally projected. I will always keep the lines of communication open, this is why I am telling all of this...

Thanks, Tony

Early Congratulations Tony, Wish you and the Misses all the best.