foundvettelifeisgood

I'm installing a Perfect Fit tremec 5 speed in my 81. It appears to fit perfectly. However, the stock exhaust will no longer fit. The new crossmember they provide dictates one pipe on either side of the tremec. I'm wondering if the stock exhaust from a 72 would fit on my 81. Specifically, I'm wondering if the batwing of the 81 rear suspension creates any issues for the routing of the older C3 exhaust systems.

Looking forward to your thoughts

foundvettelifeisgood

foundvettelifeisgood

gbvette62

Unlike 80-82 exhaust, that is designed to go under the crossmember, the 68-79 exhaust goes through two large holes in the crossmember. I'm not familiar with the Perfect Fit kit, so I can't say if their crossmember allows enough clearance for earlier pipes to go under it, but if it does, I would recommend using a 74 system. The 74 system has mufflers with turned down tips, since it was used with a rubber rear bumper, while the 72 has muffler tips that exit through the rear valance panel. The only thing different between a 72 and 74 4 speed exhaust system, is the mufflers, so if you have access to 72 pipes, you could use them with 74 mufflers.

All 68-82 exhaust systems go under the rear end in about the same manor, so I don't think the "batwing" should have any bearing on what system you use.

foundvettelifeisgood

GB, it's hard to see in these pics, but the new crossmember has flattened out thin areas where the holes were in the early stock crossmembers. It's hard to say whether the clearance in that area is the same. I think the older stock pipes jumped up at the holes to go thru them, so I suspect there could be a clearance issue. I won't know until I buy the pipes. The 1980 change to the batwing still accommodates the same rear spring configuration, so I was assuming it would not be an issue, and I'm glad you agree. I've seen 74 systems that are designed for stock manifolds, but none that are designed for long tubes.

Thanks for your input.