Post by 99for200bucks on Apr 18, 2016 14:03:06 GMT -6
I will be in a position to do a "Y" pipe mod soon but having second thoughts about doing it. The section coming from the crossover has an odd angle of incidence compared to a true "Y". Maybe there is a reason the crossover pipe extends into the exhaust stream of the outflow from rear manifold. Without the extra "void" created in the outflow stream from the rear manifold, the gas from the front crossover will be trying to make a nearly hard right turn into "oncoming traffic". I think Carrol custom cadillac is the site that promoted removing it. What if they're wrong?
If I remember right, the larger portion of the angled, curved "flap" is to the upstream side of the rear exhaust outflow, which is exactly what I would do if if I were trying to make a safer "merge lane" for the gasses from the crossover. If all the pics from "y" pipes are pretty close to the same with the longer portion of the angle flap extending more towards the upstream flow of the rear manifold, then I would suggest it is a deliberate move by GM and there must be a reason for it. Until I see flow numbers or an explanation as to why someone knows better than GM engineers (if they did it on purpose) that it's better to remove it, I'm leaving mine as is.
Think about it...
99 Aurora. Cracked block? 4.6 swap ongoing. 94 Cavalier. 30k on new 2.2 eng/clutch. Sold! 85 Bronco. 351W 4bbl. Bad fuel pmp/rear diff bearings? Diff heats up and howls loudly. 84 Riviera. My daily driver. Olds 307 w/5A heads. Q-jet W/air door & metering rod modifications. Runs great. 68 Barracuda notchback w/318. 4bbl thermoquad and Edlebrock performer modifications. Bad trans no 3rd/rev. 340 mopar standard bore block & many choice parts in the garage awaiting funds for Cuda.