Buick T Type Exhaust
- Thread starter slp99ws6
- Start date
chris kirk
Active Member
- Joined
- Jun 1, 2013
Go with the SS 3" from TR custom parts. 4" from RJC is more for people who use the 5" downpipe from RJC.
Howling Mad
Active Member
- Joined
- Aug 23, 2010
Ummm, what? There are a few threads about people using the rjc (and possibly even the gn1) 4" exhaust with a 3" down pipe so I'm not really following you at all? To the original poster do a search on here for the 4" exhaust quite a few threads about it. And if you buy into the "its only for use with a 5" dp" b.s. and you just want a single exhaust, gbody parts sells a 3" single exhaust.
- Joined
- May 26, 2001
Just an opinion, but why would a street turbo car need a 4" exhaust, on even a 3" one for a performance improvement?
It is difficult enough to route a 2-1/2" system over the rear axle and keep it away from contacting the coil springs or frame parts? Maybe the 4" system will exit before the axle?
Being new to the scene, the OP maybe does not realize as the exhaust gases flowing out of the down pipe and into the tail pipe, it becomes cooler.
As it travels further back the exhaust, restriction becomes less as the gas volume flowing in the pipe is shrinking.
So even with dual 2-1/2 pipes, there is more than enough exhaust flow for even a modified street GN not being a restriction.
This has been verified many times at the track with a low 11 sec. GN it will run the same times with or w/o the dump open.
It is difficult enough to route a 2-1/2" system over the rear axle and keep it away from contacting the coil springs or frame parts? Maybe the 4" system will exit before the axle?
Being new to the scene, the OP maybe does not realize as the exhaust gases flowing out of the down pipe and into the tail pipe, it becomes cooler.
As it travels further back the exhaust, restriction becomes less as the gas volume flowing in the pipe is shrinking.
So even with dual 2-1/2 pipes, there is more than enough exhaust flow for even a modified street GN not being a restriction.
This has been verified many times at the track with a low 11 sec. GN it will run the same times with or w/o the dump open.
- Joined
- May 26, 2001
Sorry, this was a duplicate post?
- Joined
- Jan 3, 2012
If it's a track only car with a big turbo that I can see maybe using the 4in. Otherwise it may slow spoolup and it is very loud and drones a lot on the highway. Their 3in crossflow would be a better option. I have one and if fitted properly will clear everything ok. No restriction and very little-no drone.
mikestertwo
Well-Known Member
- Joined
- Sep 13, 2006
Take Nick's advice. Unless you have a highly modified track car a 3" downpipe with a dual 2-1/2" out the back is all you need. I'm running high 10's@125+ on a very mild build with that exhaust.
chris kirk
Active Member
- Joined
- Jun 1, 2013
Wasn't saying that he couldn't use it, but why would you need it? Like I said it's designed for people using the 5" DP. And anyone using a 5" DP is making pretty serious hp. Also, you wouldn't have to waste time and money to modify it to fit 3" exhaust.
Howling Mad
Active Member
- Joined
- Aug 23, 2010
...lost. It fits the 3" down without any mods...
- Joined
- Jan 18, 2011
x2...All 3 of my cars have this, 3" dp into 2 1/2 exhaust..its all your gonna need, and my 3 cars are 12s,11s and 10s..
thanks for all the input guys....i bought a 87 turbo regal with some mild upgrades...TE60 turbo, front mount, 60# injectors, built trans...does have some kind of aftermarket exhaust now but starting to look a little beat up so i figured i would go with a new system
