exhaust question

[XcessiveBoost]

on a stock motor how would a 84 GN run with no exhaust after the downpipe???

[kenmosher]

Uhhh ... fine ... :dunno:

Not sure what the question is?

It'll be a bit loud ... you'll definitely hear the turbo spool ... it'll probably pick up a pound or two of boost.

[XcessiveBoost]

i just didnt know if it would hurt the performance or not...

[stizkidz]

I have always been under the impression that the best "bang for your buck" upgrade on any turbo motor is a free flowing exhaust. I guess a close second would be fuel upgrades (but this can be costly). Anyone want to second this?

[kenmosher]

Well, it's kind of one of those "it depends" ...

*IF* your fuel system can support it *AND* there's enough octane, turning up the boost (within reason) is definitely the best bang for the buck ($1.50 for the makings for an adjustable wastegate).

However, the TRs fuel pumps are notoriously borderline, so normally it's one of the first things to get upgraded ... more from a "solid foundation" standpoint than anything else.

Free flowing downstream of the turbo is definitely another great area for opportunity. We documented the fact that a dump tube off the end of the stock downpipe is worth about 25 HP (based on 0.25 and 2.5 MPH at the track) over a stock 86/87 exhaust system. This was on the GSCA "Project Car" where we did each mod in the Recipe and then measured it.

[gotboost231]

On a stock motor, you'd probably notice a slight bit of difference, more throttle response, but the decibal level on the freeway is definitely ticket worthy. Id leave the open pipe for the track.

Id recommend some free flowing mufflers (NOT Flowmasters, a straight thru design is better for our cars, since we dont need to worry about backpressure) and either a gutted cat, or a straight pipe in place of the cat.

hope this helps

Terrance Topits
84 GN
http://www.turbopower.co.nr/