Which exhaust?

[Turbo Negro]

I'm starting with a stock 87 GN with 98k mi's. The car runs well, and appears to have been well maintained, and driven responsibly.

Initial plans are to build up using bolt-ons with alky injection and maybe 15-20lbs of boost, and then later rebuild/ balance the engine, port & polish everything, add new cam, valve springs, roller rockers, a double roller timing chain, and bigger turbo.

I'd like to add a new exhaust system with the first set-up that will also work well with the later modifications. What should I be looking at to accomplish this: 2-1/2" vs 3" cat-back, cat or test pipe, 3" downpipe, turbo mufflers, etc?

 

[TR Custom Parts]

Depends on what your budget is. Hookers 2.5" with Aerochamber mufflers are reasonably priced but is mild steel and will eventually rust out, Pypes has a dual 2.5" system but no experience with it. Other stuff out there just do a search. The dual stainless system we sell is now back in stock....... http://buickgn.com/CatBack.htm

Do you still have to get your emissions checked? Do they still do visual inspections in your state. If not, just throw a test pipe on it.

 

[Mark Parks]

For the money Pypes with race pro mufflers.

 

[highboostgn]

Ditch the factory dp and get yourself a 3"

 

[Mark Parks]

x2

 

[Turbo Negro]

No emisions here However, I'm leaning towards a 2=1/2" system.

What are the pros & cons to removing the cat?

 

[nickygn23]

I went with the tried and true Duel Hooker Headers Exhaust System with the Aerochamber mufflers. Not too loud but nice sound. Fitment was good too.

 

[highboostgn]

No emisions here However, I'm leaning towards a 2=1/2" system.

What are the pros & cons to removing the cat?

Running the test pipe will free up the exhaust back pressure and you ll spool faster as well

 

[Turbo Negro]

Leaning toward the Hooker 2-1/2" system with test pipe now. I wonder if a high-temp clear coat would help preserve it's mild steel construction?

 

[blackgn1]

3" downpipe and single shot 3" exhaust.

 

[SpeeednV6]

Best thing I did was a Terry Houston 3" downpipe w/dump. Then I installed Hooker duals in back. The Hookers do rust after a while. I love my dump tube!! When I uncap it, it spools the turbo like mad. It is louder and drones, but I like it! I would like an electric dump because it is a pain to go under the car to cap/uncap. Food for thought.

 

[NorEaster]

I love my RJC. I think it sounds great. It is quite at idle though.

 

[Turbo Negro]

Quiet is good. I want something that flows well but is not too loud. I think I'm focused more on throttle response and low rpm improvements than all out racing. An electric dump sounds like a good option, but at a later date. I'm going to hold off on that until i decide on stage II mods. I'll likely improve the suspension & brakes before that happens. Should be plenty enough for a good scare in the meantime

 

[SpeeednV6]

With my dump closed, it is pretty quiet. The Hookers are not as throaty as say, "Flowmasters".

 

[Turbo boy]

RJC nice sound and still looks new.

 

[Fast Farmer]

For the money Pypes with race pro mufflers.

X2