GTM Stock Cat Pipe Exhaust Fit Issues

[Mkraus01]

I am using the stock H-pipe exhaust, stock Cat pipes and OBX shorty headers on a LS1 with a Trick Flow cam and header upgrade. I am having exhaust fit up issues where the Cat pipe is contacting the bell housing on the passenger side near the starter. I pressed in a flat on the exhaust and can pretty much get the pass side to fit well between the headers, Cat pipe and H pipe, but on the drivers side not so much. When I connect the cats to the header, I get a v-gap at the Cat to h pipe flange of about 1/4”. Pictures attached. Anyone have any thought/experience here on what the issue could be?

Thanks
-Mike

[Mkraus01]

So I’m the only one to ever have exhaust alignment issues? Or am I the only one not going with Kooks exhaust? :-)

I’d appreciate others feedback, whether good or bad.

Thanks

[wallace18]

Mine came together fine with the gaskets installed, but I used the factory Vette manifolds as that was what the cats were designed for. You may have to see which flange is not flat and go from there.

[VRaptor SpeedWorks, LLC]

I've only installed the FFR exhaust on one car....the very first car I built before the Kooks system even existed. I do remember that I could not get it to be centered thru the rear of the body and ended up using 2 gaskets on one side and one gasket on the other side to essentially "shim" it over where I wanted it to be.