Topic: Y-pipe to true dual

[pstein]

How much of a difference in horsepower do you think I've made going from factory exhaust y-pipes on a 1978 to true dual, long tube headers, x-pipes and glass packs?

[Mwieczorek]

Bascially what you've done is remove improve the flow characteristics of your exhaust flow path.  The big question is, what have you done to the engine to take advantage of that new found flow?  If you still have all stock engine parts and all you've done is the exhaust, you may only see 5 - 15 horsepower or so.  If you have installed a better camshaft and a properly tuned carburetor and distributor advance curve to take advantage of all that increased flow, then you are looking at a much larger increase.

Remember, and engine is nothing more than a large air pump.  You can increase the flow capabilities of the piping all you want, but unless you do something to make the pump use the additional flow capacity, you won't see any big gains.

Matt

[pat]

but it wont hurt

[Hitman]

When I did my exhaust, I gained about 25hp by going from a Y-pipe to true dual exhaust with flowmasters and headers.

[pstein]

Brett, did you have other things done to it at that point?

[Hitman]

nope, just the exhaust and a slight tune on the carb to compensate for the better air flow.