318willrun said

^^^^ alot of typing, alot of formulas, and a lot of math. Before anything can be counted on as achieving/underachieving, a goal or standard to measure against must be set. To say "that cam kills low end", then what would be the proof? The V/P.
V/Ps over 160 are soooo nice. Under 100 are very weak.
A 268* in a 7.8Scr teener is about a 94, even tho it might still have 120 psi cylinder pressure.
A true10.5Scr 340 from 1970 might of made a V/P of 144 and had cylinder pressure of 175psi
A 444stroker at 11/1, with a 276/108 cam might make a V/P of 200 and have cylinder pressure of 187. But if you put a 292/108 cam in it, the V/P drops to 165@168psi. That cam just "killed" the bottom end. To get it back she would need a compression boost to 12.8. To look at it another way, that 16* of intake duration cost 1.8 points of compression.
Certainly not a piece of paper (your way smarter than that). So what then? A 2.5 60 ft? 2.3 60 ft? Yes and No. The 60ft is all about putting down as much power as the chassis and tires can handle. If it spins it sux. With 2.45s and a 1750TC there ain't a lot of potential, for TM. So you got to start off with a a big number. If the cam trades away 20 or 30 ftlbs at the stall for about the same at the other end, then the 60 ft will be "killed"
Here's a Hughes curve;


Check out the 170# at 3200. If you hit the start line with a 3200TC and 4.30s, you would be generating 170 x 2.45x4.30=1790#
But if you swapped that 3200 out for a 4000, you'd have the potential to put down 320 x 2.45x4.30=3370#.
So if your chassis and tires were able to deal with that, it would be reflected in the 60ft.
Now extrapolate that torque curve down to an imaginary 1750 rpm. Well you can't cuz of the dip at the tip-in, but Lets say at 1750 you made 80 ft lbs. Now with the 2.45s,you are down to 480# on the line. And if the bigger cam dropped 20 off that, then you are down to a dismal 360# You almost have to wonder how it can idle at all.

What is the expectation for a stock 360 with stock converter and 2.45's in the 60 ft (providing the car hooks)?With slicks,How can it spin? I've never had a challenged combo like that so I can't say.And the answer is not in the charts,lol. But you'll know pretty soon lol.

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