351w help needed
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351w help needed
Here are the basics: 1972 351w block and internals, 1970 (D0OE) heads, putting in a set of L2446F .030 pistons, Magnum 292 cam, 700 DP Holley, and the intake is yet to be determined. My question is with these pistons and the shorter deck hieght of the '72 block and smaller chamber '70 heads how much should I have the shop shave off the heads to achieve 10.5-11:1 C.R.? All machine work was done prior since this was a remaned engine with very few miles on it when I bought the truck.
Thanks,
Micah
Thanks,
Micah
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Google........compression calculator.............
Bore..................................4.030
Rod Length......................5.956
Compression Distance...1.772
Compression Ratio.........9..06:1 w/63cc cylinder head thats with a 9.503 deck heigth
Dome Shape................... 13cc Dish- 2 Reliefs
I would deck the block to 0 or even -.010 (pistons sticking out). way better then decking the heads and more effective.
Bore..................................4.030
Rod Length......................5.956
Compression Distance...1.772
Compression Ratio.........9..06:1 w/63cc cylinder head thats with a 9.503 deck heigth
Dome Shape................... 13cc Dish- 2 Reliefs
I would deck the block to 0 or even -.010 (pistons sticking out). way better then decking the heads and more effective.
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From: Kiefer, Northeastern Okla
The DOOE heads have a 60.4cc chamber. Since the block has already been machined, and unless you know how much if any the block was decked, you really should assemble enough of the bottom end so you can bring at least one piston up to TDC, measure and calculate how much volume you're left with in the cylinder. Add compressed gasket and cyl. head volume, and figure static CR. I do it the easy way and cc the cylinder the same way I do the heads. Can't get any more accurate than that. You may find you don't want to cut the head at all, in order to keep a decent CR.
292 Magnum and 11:1 CR? Is this a street motor?
Pete
292 Magnum and 11:1 CR? Is this a street motor?
Pete
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Ok, I know I have a 9.48 (?) deck hieght with the shorter rods, I put in a piston with the standard rod (5.969?) and it puts the piston almost flush with the deck. With the longer rod it gives me the same effect almost as hemieater spoke of with decking the block. Pete, can you tell me an easy way to cc my head?? I am sure it was milled when it was rebuilt. And this is going to be a "toy" that will see some street time and will go to the track/shows also. I love an engine that lopes to the point it almost dies.
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From: Kiefer, Northeastern Okla
http://www.advanceautoparts.com/engl...20020701cr.asp
I don't know if it matters much to you, but running a CR that high is going to require premium fuel, and posibly a premium-race gas mix, to prvent detonation, especially with iron heads. Also a cam with those specs is going to give you lousy mileage, and may cause problems with not power brakes not having enough vacuum. Not saying it shouldn't be done, just saying it's probably not the most street-freindly grind.
Pete
I don't know if it matters much to you, but running a CR that high is going to require premium fuel, and posibly a premium-race gas mix, to prvent detonation, especially with iron heads. Also a cam with those specs is going to give you lousy mileage, and may cause problems with not power brakes not having enough vacuum. Not saying it shouldn't be done, just saying it's probably not the most street-freindly grind.
Pete
