Originally Posted by Lgt07
Spamming this question around here Dave in hopes someone knows lol. I now have a full one piece exhaust from the cat back to the mufflers so should I to use those spring bolts like the factory does to allow some movement or should I just stick with regular bolts.
If you are still using a donut gasket at the connection between the downpipe and your catback, use the spring bolts--they'll make life easier. I've gone both routes and used regular bolts for a while due to the fact that my spring bolts were all rusted out and it was much harder to get the seal right.
If you have two flat metal flanges there now (aftermarket downpipe, i.e. invidia), and are using a metal gasket or similar, just use regular bolts.