[stahlight]

This is my dual exhaust set up, it sounds wonderful and was cheap to do.

The Y-pipe is fed from the spot of the original factory muffler feed, and is simply made from cut and welded pipe. The 2.5" exhaust tips are welded to the Y-section. I left the resonator on the car for back-pressure. I haven't been able to time-test it at a track yet, but I can say the car is far more torque-y and will chirp the wheels much more than it did before. Did I mention it sounds sweet?

 

[Blackrider]

Wow that much be loud I can imagen that sounding good, because i've herd mine with just the res.

As for back pressure, you dont want ANY. You want exhaust gas valocity.

 

[stahlight]

back pressure?

About back-pressure:

it's a commonly held conception amongst most (especially older) car people that "proper" back-pressure is needed for maximal torque from an engine and that some engines "wont run properly" without back-pressure. Yet when quizzed about how back pressure affects torque are unable to provide even a qualitative description.

Does anyone have the scoop on this?

 

[bristol16]

i thought backpressure also contributed to exhaust scavenging and actually helped the exhaust flow better because instead of the forcing the engine to push the exhaust out it was also pulling itself out at the same time.

 

[Hambone]

Bristol is correct

 

[Blackrider]

i thought backpressure also contributed to exhaust scavenging and actually helped the exhaust flow better because instead of the forcing the engine to push the exhaust out it was also pulling itself out at the same time.

That’s a different Phenomena. For peak HP you don’t want ANY Backpressure, you want exhaust gas velocity. That doesn’t mean straight pipe provides that.

 

[stahlight]

A guy told me that back pressure -also- flattens the torque curve making a car faster off the line. I need to time my mods vs a stock G6 to see if this is true.
It certainly acts more peppy.

 

[GTPGuy82]

absolutely no back pressure = crappy running engine

 

[Blk02Ls1A4]

That looks like it would be a little loud for me, but if it sounds good to you then it is all good!! Here is an interesting article on exhaust...
http://www.popularhotrodding.com/enginemasters/articles/hardcore/0505em_exh/index.html