Re: Let's build a drag race 8BA engine
The Highest compress you can get, on one of these engines, will be with FT pistons, with a CH or stroke set to get your piston within .042-.038 (possibly .036) of the head.
Even getting a dome head up to that clearance, will be a little less, because the dome shape, has more area than a flat. The transfer area shape, also will make a difference to the CR. The difference of how high the top rings is, also has a minor effect, as well as how thick the valve margin is.
Also, after posting my sim HP/TQ estimate, I asked around, on different sites, to find flow numbers on our engines. I found flow bench numbers, The guy, cut up a block, to mount on his bench and ported and installed 1.6" valves but, I only got the intake flow and I estimated the exhaust at a few cfm less, although I think the exhaust will flow more.
Anyway here are my revised numbers and what this flow looks like when added to the program.
Again, it's 239, 9.2 CR FT piston .038 head clearance, 1 carb on the stock cam and 3 x 165 cfm on the big cam.
In think the stock cam sim HP, is believable, take the 262 @ .050 cam, with .440 lift -.012 at what ever you want, it a pretty radical cam!
I would like a opinion, if possible, on the accuracy of peak rpm (5400) with that cam. The valve events are:
Lobe Lift .010--.020--.050--.200-- Max lift- .440
Duration 315.9-286.8- 262--189.5
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Frank
'35 Ford Model 51
'48 Ford F3
'54 Ford Tudor Mainline
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