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Your cam specs are often listed as both lobe lift and valve lift. Take lobe lift and multiply by 1.7 to get valve lift.
 

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Correct - and if you don't have the lobe lift, divide the lift spec listed by 1.6 and then multiply by 1.7

For example, the stock cam is listed at .444 lift. Divide by 1.6 and you get the cam lift .2775 then multiply by 1.7 and get .472 ( rounded up )


Another consideration is the 1.7 ratio opens and closes the valve this additional distance in the same duration. If you graph out the valve events, you'll see more area under the curve. The effect is the valves move a little quicker.

Comp cams extreme energy series sorta works this way. Compared to most cams of similar advertised duration, there's not as much of a difference in lift figures at .050 lift compared to advertised.

Basically, the lobes are more aggressive - aka steeper - and the valves are opened quicker. This is desireable so long as you have the proper springs to control those valves.
 

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Just what I'm running. TFS heads, stock cam, 1.7 rockers... I'm not sure whether it's those items, or the little 5 psi blower, but it seems to run really well. The power curve is much like I remember from my 5.0 mustangs, but moved higher up on the scale, ie. lots of low end torgue and hp, just more of it. I've got a decent lope, too. Not like a B cam, but closer to it than stock, maybe just from a lower idle, but I have no complaints.

Dave
 
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