2 1/2 inch exhast
I've had several "early sharks" with headers. Those conventional style under car headers really heat up the floor board areas, actually softened the sole on my sandals. If you run a wider than stock original F 70 15 size tire, such as 245 60 15 radial, it puts the ground clearance even smaller, causing the header flange to scrape.
I've also had the sidemount exhaust headers, still a fair amount of heat build up, less ground clearance issues, however you end up carving a small portion of the rocker sill moulding out and cutting a small section of the fiberglass body sill out as well for header tube clearance.
I'm back to factory exhaust manifolds and a mandrel bent exhaust piping. Stock tire diameter is 26.06 inches, a 255 60 15 is 27.00 inches and probably the closest for revs per mile to keep accurate speedometer reading, but I think the section width of this tire is like 10.2 inches, it may rub on the front, not sure.









