Difference between 3.0 & 3.5 THDP?

[gnjay]

Do they both mount up to the stock exaust. And what are the pros and cons betwen them?

 

[Louster38]

Do they both mount up to the stock exaust. And what are the pros and cons betwen them?

If youre considering a 3 or 3.5" DP, you shouldnt have a stock exhaust. Either way, it won't just match up to the stock exhaust, either the cat or test pipe has to be the same diameter as the downpipe. Unless you have a really aggressive setup, you shouldnt need a 3.5, but in theory that would flow better. Con: Might be hard to find enough clearance with the AC/heater box. Most likely a 3" would be best, and if youre going to be swapping that then you should be getting rid of the stock exhaust too.

 

[tbirdv6]

The stock catback can be just as restrictive as the stock DP
Best thing to do :

stock turbo- GT67 = 3" DP
GT/PT70 & up = 3.5"

Hooker Catback(Summit $279 shipped? w/Aero Flow mufflers)
FRED

 

[mcponch]

3" 3.5"

ITS THE DIFF BETWEEN, LETS SAY. ME AND A BULL. YEAH A BULL. IM .5 BIGGER. FRANK.

 

[tbirdv6]

Bigger is not always better
I have both available
FRED

 

[gnjay]

Thanks guys, I guess i'll be going with the 3inch down pipe. Can I still run low 11's with the 3inch down pipe and 2 1/2inch exaust considering that I have the right turbo ect?

 

[Race Jace]

bigger is better when it comes to DP's. One problem you run into with the bigger down pipes is clearance. if they rub they make a heck of a racket. 3.5 to 3" does not seem like much but sometimes a picture is worth a thousand words.

 

[Race Jace]

also any DP you get should come with a test pipe or cat as an option, all of these will work with stock exhaust and most aftermarket cat back exhaust systems because all retain the stock style 4 bolt cat flange.