Stillen or gtm supercharger?
 

I am looking into getting a supercharger but cannot make up my mind. Both brands are well respected. Please help me out from your knowledge and experience. Thanks

Oh boy... be ready for the "Use the Search" assault...

I think it is safe to say that the GTM kit is more used and respected HOWEVER a few folks have had great success with the Stillen kit... notably RCZ.

GTM uses the Rotrex kit which, in my opinion, has more potential than the other centrifugal and roots style kits.

There is an interesting read regarding someone who switched from Stillen to GTM floating around and I think their opinions are valuable considering they experienced both.

And one more thing... tuning, tuning, tuning!

If you like a really clean looking engine bay go with the GTM kit. The GTM kit is a proven performer, And with the stage 2 finally becoming available there is really no other kit to look at

Right now the GTM stage 2 SC kit is a really good deal for 500WHP...

You might want to order it before he raises the price.

If I ever feel the need I will upgrade to the stage2 kit.

Search button is ur friend. But go in the forced induction thread.. You will see more gtm them stillen. Interesting I haven't seen stillen on here in a while

Ibtl

GTM seems to get good reviews from everyone...stillen seems to get good reviews mostly from people they sponsor.

What about performance between stillen and gtm stage 2?

err... uhh... why would this be locked..

How long and how much are these installations ?

Because every gtm vs stillen thread turns bad. There's atleast ten of them

i just wish i had half the money i would need for either kit!

If you are interested in making more power, the Stillen kit uses a Vortech supercharger which is capable of flowing more than even the stage 2 Rotrex unit that comes with GTM. However, people have had hit or miss experiences with Stillen kits while everyone with a GTM kit is extremely happy. Most of the praise that the GTM kit receives is the smooth and easy driveability, linear power and torque output, and a very clean install.

I would say that the GTM stage 2 supercharger is the best FI option out there for the Z as it retains linear and instant power delivery which I feel suits the precise and balanced handling of the car. Turbos can't deliver that experience in my opinion.

In regards to the Vortech supercharger's flow capabilities vs. the Rotrex, there was a discussion in this thread: http://www.the370z.com/forced-induct...ailable-5.html regarding that.

The result of that discussion was that while the compressor that the Vortech uses may in fact flow about 2% more air than the Rotrex, the rotating assembly of the Vortech cannot spin fast enough to actually achieve what the compressor is rated at.

About 5 years ago, before we started even developing a supercharger kit, we had a customer with a G35 and a Vortech supercharger kit. As far as I know, we are the only company to achieve over 500whp with the Vortech, and that was using their biggest supercharger (T-Trim). When I say that the rotating assembly just can't handle spinning high rpm, that comes from experience...that supercharger failed 3x trying to push 500whp. When we tried to get the unit warrantied, Vortech came back and said that we were over-spinning the blower...keep in mind that this was on a DE car with a 6500prm redline. The customer finally gave up on the Vortech and went Twin Turbo instead.

The thing about the way the Vortech is rated that people are forgetting is that those blowers were designed specifically for V8 engines with low volumetric efficiency. What this means is that they produce more boost at lower rpm on an inefficient motor. Remember that boost is nothing more than a measurement of restriction. On the VQ motor, the Vortech has to spin higher than it is capable of spinning in order to produce enough boost to make it's rated power.

The Rotrex blower on the other hand was designed specifically for high efficiency engines and is capable of spinning to high rpms with very little parasitic losses. So in essence, you'll never see that extra 2% flow the Vortech is rated at.

I also want to point out that our stage 2 supercharger kit is using a fairly large pulley and isn't even maxed out yet. There was a member who pretty much did every modification under the sun you could possibly do to a Vortech and still doesn't quite make what our Stage 2 kit does out of the box.

There are a few people that have gotten more than 500whp on VQ35DE.Here is one guy with a SC Trim with a 928 impeller built motor.

Vortech tuned with Motordyne XYZ pipe and ART Pipes...interesting results - MY350Z.COM Forums


Here is another build done on a dyno dynamics with a T Trim.This car made a max of 530WHP. http://http://my350z.com/forum/force...ake-power.html

Now I get where you are going when you say Vortech's are designed specifically for V8 engines with low VE.However there are plenty of E90/E92 M3 with kits from ESS and Gintani making well over 500whp.Those motor's are not inefficient low rpm motors,they rev all the way to 8500 Rpm's with Vortech Blowers.

Now as far as the way the GTM kit is designed compared to Stillen's kit :tiphat:to you guys at GTM.You guys Stage 2 looks promising.

Considering that the Stillen Kit does not come with the 928 Impeller or a T-Trim it's comparing apples to oranges.

I was specifically addressing the comment regarding the base Vortech blower in the Stillen kit being bigger than the base C38-91 Rotrex blower in our Stage 2 kit.

In fact, my comparison of the Vortech T-trim we did in this thread: GT Motorsports: 500rwhp/455rwtq Vortech T-Trim, FCon VPro, GTM Built Engine - Page 2 - MY350Z.COM Forums is apples to oranges as well. The main point of me mentioning that particular build was to illustrate that the Vortech simply cannot handle spinning that high for very long. Remember, that car ended up going through 3 blower failures.

As far as the 928 impeller being better, that is an additional cost to the base Stillen kit and causes you to lose the warranty that Stillen offers. Even with the 928 impeller, the graphs speak for themselves:

GTM Stage 2 Supercharger Kit


Here's your graph from your thread.


Please don't take this the wrong way as I really commend you for pushing the envelope with the Stillen setup. :tiphat: Since you are the only person with the 928 impeller on a 370Z, I have couple questions.

1) Do you think it was worth going this route? Would you recommend it to other guys with the Stillen kit?

2) Are you maxed out with your setup or do you think there's more in it? The reason I ask, is I don't know what your impeller speed is at redline. How much more can you spin that blower?