They say (at least on the phone) that all their mods/gains are measured in WHP.

Not sure what you mean? You saying they wont make 425WHP? You are right if your saying their kit and their "box" tune, Heck I made NA 298 WHP on their tune I only made 342 WHP:confused::confused:

UPREV tuned made 412 WHP:driving:, Just proves their tune SUX..

Every plan to get around CARB has risks. If you are going to do the out of area registration, make sure your driver's license matches. It is a red flag if it doesn't. If you get popped near your house, the chances increase that you'll get popped again by the same cop and he'll then know whatever story you told about just visiting is BS.

GTM will never have a CARB certified kit, so OP go ahead and buy the Stillen kit and get a good tune for it. Yes it wouldn't be CARB approved anymore, but no one will know.

You know what, looking over all their info again... The Stillen kit looks just fine. I think every member that has it is actually making the numbers they promise 480-510hp, and they get around 420-430WHP...
I thought they always advertised WHP numbers and gains (which they told me on the phone) but it looks like for their S/C kit, they measured WHP and HP at the flywheel

The purpose of getting a stillen is for the CARB certification right?

You'll never make those numbers with the stillen kit.

custom tune and upgrades yes, but then it is no longer CARB certified. Risk serious fines to hope to make what other kits make with ease? To each his own I suppose.

a custom tune without changing any parts kills the carb certification? How would they know as long as you have the sticker?

Yes, changing anything from the setup that was tested technically voids the CARB certification. There is no way in hell they would know it had a custom tune, though.

then you're all good, just gotta get that sticker, haha

If you want to play that game, there's no way they would know you changed out injectors, pullies or tune.

An wouldnt know you changed anything, the Impeller is not visable, an if you upgrade the heat exchanger they cant say anything. That would be like "sorry sir you fail for having a larger raditor" LOL

As ANMVQ stated in the first page, the Stillen kit with a custom tune is not bad whatsoever. Its still a better alternative than going the n/a full bolt ons route, if you are calculating horsepower per dollar. Purely lacks for room to go close and beyond 500whp... Which EVERYONE says they want to hit, till they get their car back with the extra 100+whp. If you aren't looking to build the engine to handle more power, then this would be one of better options that we suggest to our customers.

Would Stillen have a problem if I asked them to change their pulleys and bypass valves to something not plastic? People seem to say those need to be upgraded as well as possibly the injectors.

In all honesty if I go back FI and dont go twins low boost ( Save the auto tranny and t case) I will be going back to the Stillen Kit.

I didnt even realize the pullies where plastic??? But I went with a upgraged BPV anyway.

Some of us are still hoping for a GTM CARB approved kit, but I fear you're right...