So i bought a used spm cat back yesterday i mated it with my spm downpipe.... my problem is that the rear pipes dont sit evenly at the rear.... one is noticably lower and off centered than the other...
This is normal because there is no gap for the junction between the downpipe and the catback. When I installed a SPM downpipe for my friend, I pulled the catback far way out to slide the clamp. Even I did it, the downpipe just stucked and there was no way I can connect the catback to the downpipe. To solve your problem, you might wanna cut at least 1 inch either for the downpipe or catback in the junction.
that particular problem has nothing to do with the length of either part, its a side to side issue. its just noticed even more when the tips stick out an inch too far. almost everyone has that SPM issue whether or not they notice it. SPM was my most favorite catback I ever 'heard', and I've had quite a few. You need to get clamps or collars on the hangar pegs to force it into a better position side to side. that being said, the "new" "recent" SPM catback I just installed a couple months ago on someones car was very good fitment. I think the older versions were more sloppy. The one below in this video was pretty good out the rear as you can see.
Hose clamps are your friend. You can wrap them around the rubber rear hangers and tighten until it's even height wise. Side to side can be adjusted with smaller clamps around the exhaust hangers to wedge against the rubber hanger.
that particular problem has nothing to do with the length of either part, its a side to side issue. its just noticed even more when the tips stick out an inch too far. almost everyone has that SPM issue whether or not they notice it. SPM was my most favorite catback I ever 'heard', and I've had quite a few. You need to get clamps or collars on the hangar pegs to force it into a better position side to side. that being said, the "new" "recent" SPM catback I just installed a couple months ago on someones car was very good fitment. I think the older versions were more sloppy. The one below in this video was pretty good out the rear as you can see.
that's not that bad man.. you can't even tell the one tip lower thing, at least i can't. and to fix that left tip which is too much towards the outside, loosen your metal bracket on the other side, which is slotted. Pull that bracket side as far as it can to it's outside and tighten the bolts. You might be able to squeeze 1/4" side movement out of it which would make it almost perfect. Unless you already did that step...