Hi im getting a greddy TT kit pretty soon but need to know what exhaust is good. Right now i have the OEM exhaust, im leaving the kit in stock boost do u guys think the stock exhaust wont cause any problems at that level of boost. I want an exhaust that is 3 inches or more in diameter the only ones i know are the SFR hks carbon TI and aps 3.5 in diameter any other ones. Thanks

 

Think about where you want to take this project. Is your car gonna be on a stock engine? If so there are safer solutions out there. In case you don't know Greddy TT kits have been on the most motor failures. Some say tuner other says kits. It seems to be the kit of choice if you build the internals.

APS makes a great kit but is not that user tuneable. So decide what you want and as everyone will say, use the search button. Your answers are out there but you need to find them. Also this isn't a cheap hobby be prepared for all sorts of things needed.

 

He asked about exhaust, not APS vs Greddy. I think stock exhaust will be ok at stock boost levels. I know Charles(phunk) has tuned cars to over 400whp on the stock exhaust, so you should be ok.

 

If you are running stock internals, 3" or 3.5" is overkill. the aps 2.5" exhaust will be more than enough flow for 400rwhp, which is about where you will be on a stock block. unless you are aproaching high 500's into 600 rwhp, you won't need a 3" dual.

 

The problem is that what im going to do is leave it in stock boost(5.6) pounds and then start modding but i dont want to buy two exhaust im going to get the one thats going to stay their for the future.

 

What is your final whp goal? If you are shooting for less than 525whp the 2.5" is enough, but if you are wanting more than go for the 3".

 

This is a hijacking!

+1...The greddy kit does not have safety features to keep it from blowing motors like the APS. I'm not talking about the fuel solution either. I am talking about the actuators that don't let most people boost past 10psi or the locked engine management that can not be tuned unless you are an authorized unichip dealer. And if you are not an authorized unichip dealer and want to become one, the price tag is $5K, which sways most shops away. Bottom line, it not the greddy kit that is blowing motors, it is the installers and tuners.

 

+1 again on tuning/installers, not the kit that is blowing the motors

 

Main questions you need to ask:

a) are you remaining a stock long block , if so any good 2.5" exhaust will be more than adequate since you will never get of 500rwhp safely.

b) are you building the long block , if so a dual 3" exhaust will provide the best growth potential since >600rwhp is safely possible. You don't need dual pipes over 3", all they will do is eat into your precious ground clearance with no performance gain .