Gmc/Chevy has these 3.6 V6 with the exhaust manifold collector cast into the head. There is a single port exiting the head on each side.
It then goes through a pipe with a cat, and then on the Chevy Colorado/gmc canyon, finds its way into a real crappy, unequal length “Y” pipe that has a cat/resonator in it... It merges there and then goes to the back through a muffler and resonator.
I really am at a loss for trying to find power in this bit of pipework. Getting rid of the cat/resonator (not sure which it is) reports gains of about 15 whp on the dyno with little to no tuning.
If I’m going to take the resonator out, I was debating fabricating the Y pipe into as close to equal length as possible for the collector.
Space is limited but I could probably get real close to equal length if one of the tubes has a real tight 180 U... not excited about that.
So I guess my question is, does the equal length of the piping matter since the merge collection of 3 cylinders has already occurred in the cast head?
Does it matter how close or far away the y pipes collect from 2 to 1?
I’m trying to find pics and post.