Biggest Size Exhaust for Stock or Stockish Set Up?

[2001_F250]

Well, I want to put a nice cold air intake and get a tuner for my truck, to let it breathe better and get a few hp out of the engine. And I was thinking of having a local exhaust shop build me a straight pipe turbo back exhaust, but I was wondering how big should I go for optimal horsepower gains? Also, what size is the stock exhaust for comparison. Well, thanks.

[sean400]

4" or 5" i dont think you'll be able to clear anything larger than 5" due to firewall restrictions.. also 4 or 5 should be more than plenty to get the hot air away from the engine

[Cjcross22]

Stock is 3.5".

A 4" down pipe into a 5" would be plenty. Or even a 4" all the way out. Some say just a muffler delete is sufficient though.

[01Crewcab7.3]

I have been told that 4" and 5" will flow almost the same just the 5" has a different tone. Just out of curiosity how come you are going to have it custom made? Just don't like the exits available? Because there are a lot of kits out there that would probably be a lot cheaper.

[Toms01PSD]

I would buy an exhaust from a company before I have an exhaust shop build me a 'custom' exhaust. I brought that up to a local exhaust shop and he was honest with me. By the time he ordered 4" pipe and welded me up an exhaust I could have bought a turbo back kit for way less than he made it.

[Vdryv]

By the time and money u pay a shop you could just. Uh a mbrp or diamond eye

[2001_F250]

Thanks for all the info guys. Guess I'll look into the MBRP set ups that every one is using. Figured it would be cheaper to have a shop make it, but maybe not. I'll see what I decide to do. Well, thanks again.

[Toms01PSD]

I bought mine through XDP. It was just the performance series turbo back kit. Let them know you're a member on here and they give you a discount.

[2001_F250]

Thanks for the tip. I am considering getting the 5" straight pipe because I prefer a nice throaty sound and want to be able to hear the turbo better. My last car was a '94 Trans Am with a 350 LT1 and a 6 speed, it had longtube headers, catless y-pipe, and Magnaflow catback.

[Toms01PSD]

Originally Posted by 2001_F250

Thanks for the tip. I am considering getting the 5" straight pipe because I prefer a nice throaty sound and want to be able to hear the turbo better. My last car was a '94 Trans Am with a 350 LT1 and a 6 speed, it had longtube headers, catless y-pipe, and Magnaflow catback.

With that setup i'm sure you'll hear more exhaust than turbo. I straight piped my truck stock and it was loud!

I had a 95 S10 with a LT1 in it. Headers and true duals out the back. Had a subtle idle then when you got on it everyone heard it. I know the feeling.