D0VE head compression
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From: Sussex
D0VE head compression
I recently purchased a 460 with D0VE heads and C6 for $400. By the condition of the 1971 Lincoln it came out of, it is believed to only have 59,000 miles on it. I know it has 10.5:1 compression, but i was wondering what that converts to in PSI. Thanks for any help.
Ryan
Ryan
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Mountain Pass
Joined: Aug 2004
Posts: 143
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From: Tacoma, WA.
All stock untouched pre 72 BBF's I have checked...
Have cranked at 190 to 210 PSI. This is too high for the pump premium ala' cat pee we have today.
This is why the aftermarket provides dished and below deck pistons to get the C/R down below 10 to 1 or the cranking PSI in the 165 to 175 PSI window.
On the flip side a bone stock mid 70's to mid 80's 460 with its 27 cc dished pistons, .025" below deck and D3 cylinder heads cranked at about 125 to 145 PSI with a stock cam and pathetic 7.8 to 1 actual C/R.
Keep in mind that there is not a direct corrolation between C/R and cranking PSI unless the cam specs remain the same. Change (increase) the cam duration and more importantly (delay) the intake valve closing point and the cranking psi will fall for a given static C/R...
In order to run on todays pump premium you must keep cranking PSI below 200 to 210 with aluminum heads regardless of cam choice and 180 to 190 with iron heads regardless of cam choice. More cam needs more static C/R to achieve these targets.
SMJ/RHP
http://reincarnation-automotive.com
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This is why the aftermarket provides dished and below deck pistons to get the C/R down below 10 to 1 or the cranking PSI in the 165 to 175 PSI window.
On the flip side a bone stock mid 70's to mid 80's 460 with its 27 cc dished pistons, .025" below deck and D3 cylinder heads cranked at about 125 to 145 PSI with a stock cam and pathetic 7.8 to 1 actual C/R.
Keep in mind that there is not a direct corrolation between C/R and cranking PSI unless the cam specs remain the same. Change (increase) the cam duration and more importantly (delay) the intake valve closing point and the cranking psi will fall for a given static C/R...
In order to run on todays pump premium you must keep cranking PSI below 200 to 210 with aluminum heads regardless of cam choice and 180 to 190 with iron heads regardless of cam choice. More cam needs more static C/R to achieve these targets.
SMJ/RHP
http://reincarnation-automotive.com
.
.
.
Last edited by The "Mad Porter"; Mar 25, 2005 at 11:02 PM.
