I think you're gonna come up short. I'd buy a 50' and 25' roll, just to be safe. I used two full, 50' rolls on my snowmobile pipes this winter and I can't see any long tube header taking much less wrap than one exhaust pipe. Where you really end up using it up is in the sharp bends. You have to overlap several times to keep the wrap as tight as possible. The end results are worth it though....
Before
After
Before
After