My opinion

(EDITED - Werby's test should be done first to see where you are)

My opinion, entering based on convenience and cost savings logic. (and I reserve the right to change my mind by the minute LOL)

- I dont think the exhaust is that bad at 2.5 inch, with good mufflers and a 1 3/4 primary, I think that street combo is pretty good

- If you go with a more modern cam, you "may" have clearance problems, although I'd bet 282S would work OK. But of course then you need to break it in and that can be a pain nowadays. That cam also has a bunch more lift and earlier timing which will compound the clearance challenge (Although someone else can chime in if a 282S fits with stock pistons.

- If you replace the chain with a modern adjustable and advance it 4-6 degrees (I'd even go more, screw the peaks LOL, I like early cam timing on the street on a short stroke FE) you'll get some low end for no more than the cost of a timing set and gaskets

- Then if it didnt have the top end, you could tighten the lash a little.

Of course, my logic is, least cost, least risk. If you want to assume more of either, a cam change is the next level



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- 70 Fastback Mustang, 489 cid FE, TKO-600 5 speed, 3.70 9 inch
- 71 F100 shortbed 4x4, 397 cid FE, headers, Street Dominator, 280H, 5 lug Dana 60, 4 speed