mods951

I have a 1988 Turbo S and i was thinking about getting the 3inch testpipe w/ the cat, and the 3inch catback and was wondering what kind of gains i could expect? Which system sounds better the bullett or borla in your guys opininion? Can you get both in oval or round tip? The car is completely stock as of now. Any help would be greatly appreciated.

autox951

There is the 3" test pipe and the TRUE 3" test pipe. If you're leaving the stock turbo on the reg. 3" is fine, but if you're going to get a bigger turbo the true 3" is best.

mods951

Im gonna leave the stock turbo. Any idea of what kind of gain i would get?

stewardx

There is the 3" test pipe and the TRUE 3" test pipe. If you're leaving the stock turbo on the reg. 3" is fine, but if you're going to get a bigger turbo the true 3" is best.

can you explain the difference to me?

Wes

Ski

you might get a bit faster spool up time from freeing up the exhaust a bit

autox951

The 3" pipe inlet is really smaller than 3" then opens up to a full 3". the true 3" is modified to be a true 3" you can see them at speedforceracing.com

95Juan

depends on what supporting mods you have and how clogged up your cat is to begin with.

havent some people seen like, 30+ on relatively mild cars?

seat-of-the-pants told me that i got at least another 10-15 with the cat delete/wastegate dump, but then again, i'm holding boost to redline alot better even with the stock wastegate by dumping it......

i say do it and dump the wastegate.

jimbo1111

With a full 3" exhaust you have to also replace the down pipe. If you plan on keeping the stock turbo than you don't need it. The end of the down pipe funnels down to 2.5". Most 3" cat bypass sections start at 2.5 at the flange than go right to 3". Some people never pick that up. Look closely at the flange on your LR,or Fabspeed. You will see a bell reducer right at the flange.

jean_noir

I know to get the benefit of the true 3" system you need both th 3" down pipe and the true 3" cat-bypass. BUT WILL SFR'S TRUE 3'' CAT-BYPASS ATTACH TO THE STOCK DOWN PIPE? I need a cat bypass now and can wait for the down pipe when buy a new turbo.

951Boost

I would have to say no. That is why they have the two different cat bypasses. One to fit the stock down pipe and one for the 3" down pipe.

Check out the difference:

http://www.speedforceracing.com/imag...xhaust_9_3.jpg

http://www.speedforceracing.com/imag...xhaust_9_2.jpg

TRWright

Guys, the true 3" exhaust will NOT bolt to the stock downpipe because it would not be 3". The whole idea behind it is to have a TRUE 3" exhaust from the turbo back. Not a 3" test pipe that flares in to bolt to the smaller diam downpipe.

If you have the stock turbo, your money will probably be better spent elsewhere. Just get the test pipe and catback. If you want to go TRUE 3" later (like when you replace the turbo), you can buy the 3" downpipe and have Tim modify the regular 3" test pipe into a TRUE 3" test pipe.

special tool

I know a guy who did exactly that, Ted - decent results were seen.

mods951

Ive decided to just do exhaust on my 1988 Turbo S and leave the rest of the car alone. If i do a 3inch testpipe with highflow cat and 3inch catback will the car less torquey just driving around normal? Also would it be more hp and tq through the whole rpm range or just up top? Im probably going to do one and then the other later which would you do first? thanks Andrew

Bri Bro

I put on the Fabspeed exhaust (SFR) on the 87 which has a stock engine. Like you, I want to be able to go back to stock so changes have to be quickly undone.

The cat back did little but the test pipe caused the boost to jump by two pounds, I had to dial it back to 15 were I want it. I am not running the hi-flow cat but I will put one on later. The sound is a little throaty but it isn't too loud. It also holds boost pressure better at high RPMs and that will help increase the straight away speeds. I didn't see any real gain on were the boost occurs, but it does pull a little harder.

mods951

If i gained boost from doing the exhaust would the computer compensate with more fuel? Also does the car feel any different just driving around town? Thanks again