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Discussion Starter · #1 ·
Theres a chance I may be able to get my hands on a pair of edelbrock rpm heads for similar money to my building up a pair or rhs pro torkers,
but wanted to know if they will work with my motor?

the heads are the performer rpm 6073 64cc heads.

the engine is a 2 bolt mains 357
new cast iron eagle crank
speed pro hypertectic flat top pistons 4v reliefs
Performer plus cam.
performer inlet manifold
tube headers
600cfm holley

I had been building engine on the assumption of 300hp with the pro torker 12402 heads 67cc chambers giving a static compression ratio of around 9.5.1

but running the sums the 64cc rpms would up it to around 10.1.1 static c/r

Do you think I will encounter problems with piston to valve clearance?
would that small cam run ok with the heads? not to bothered if not making full potential as can always upgrade at later date, or will i need to change this out?
 

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Unlikely you will have PV clearance issues, but you have to check this no matter what.

More importantly what cam shaft? If you were targeting 300HP it sounds like a mild cam and that will drive your dynamic compression up, so starting off with a static compression of 10.1:1 seems pretty high. Are you wanting to run 87 octane pump gas? Are you already dead set on your pistons?

Check this link to match your cam and compression ratios (note the intake duration here is listed in degrees at .050" lift):
http://www.crankshaftcoalition.com/wiki/Cam_and_compression_ratio_compatibility
 

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190 Posts
Discussion Starter · #3 ·
Silver Surfer said:
Unlikely you will have PV clearance issues, but you have to check this no matter what.

More importantly what cam shaft? If you were targeting 300HP it sounds like a mild cam and that will drive your dynamic compression up, so starting off with a static compression of 10.1:1 seems pretty high. Are you wanting to run 87 octane pump gas? Are you already dead set on your pistons?

Check this link to match your cam and compression ratios (note the intake duration here is listed in degrees at .050" lift):
http://www.crankshaftcoalition.com/wiki/Cam_and_compression_ratio_compatibility
the short blocks built & on the stand, so that is a set constant, however I am willing to swap cams if required.
the cam shaft fitted has specs as follows

BY2291730 262-400 1957-94 "Performer" flat tappet camshaft- idle to 5500rpm
Duration @ .050" lift = In 204, Ex 214, Valve lift = In .420", Ex .443", Lobe sep 112.

standard uk fuel is 95 ron super unleaded is 98ron
 

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190 Posts
Discussion Starter · #5 ·
F-BIRD'88 said:
Its up to you. You can have more power and performance with a bit bigger cam
in that motor.

Without more specific info about the car and purpose I cannot give a cam recommendation.
Ah right, I was led to believe that with my mild cam & 10.1 static compression the dynamic would be to much & not work.

The engine will be fitted to a little 1956 ford popular , old sit up & beg hotrod, mostly street driving
 
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