Meep-Meep
дворянин
Got some real numbers and I thought I'd post my findings as an FYI thing.
Quick recap. I'm building a 440 for my 66 Belvedere based on a 77 block. I will be using the 915 heads with 2.14/1.81 valves (pocket ported of course), KB237 pistons and the MoPar .455" cam. The block is pristine and was all original when I got it, so no line honing, etc...
The CC numbers are as follows:
915 chamber with big valves and one light surface cut = 79.5 CC's
Piston at TDC is about .023" below deck and that volume CC's out to ~ 14.25.
Compressed Fel-Pro head gasket (.045") by itself on a granite block is 16.5 CC's
uncompressed steel shim (.035") was about 11 CC's. I figure that's ~ 5.5 CC's per .010" of gasket thickness so a compressed steel shim head gasket I believe is around .023", which puts the compressed volume at maybe 6 CC's. The calculated CR with the Fel-Pro gasket came in at 9.2:1 and with the steel shim I get 10.1:1.
Using the #1 intake cam lobe as a reference the .455" cam lift measured .462" at the retainer with a duration of 288 deg @ .004". The .509 measured a whopping .517" lift and 318 deg duration @ .004". I used a solid lifter and the appropriate push rod with a crane adjustable rocker set at zero lash to get the cam data.
Installed centerline on both cams came in at 109 deg with an Edelbrock roller chain in the straight up position. Advanced 4 deg and I got 105 CL.
I decided to go with the steel shim gaskets and the .455" cam. If I use the composition gaskets I would run the .445" cam advanced 4 deg to gain that bit of lost cylinder pressure.
Quick recap. I'm building a 440 for my 66 Belvedere based on a 77 block. I will be using the 915 heads with 2.14/1.81 valves (pocket ported of course), KB237 pistons and the MoPar .455" cam. The block is pristine and was all original when I got it, so no line honing, etc...
The CC numbers are as follows:
915 chamber with big valves and one light surface cut = 79.5 CC's
Piston at TDC is about .023" below deck and that volume CC's out to ~ 14.25.
Compressed Fel-Pro head gasket (.045") by itself on a granite block is 16.5 CC's
uncompressed steel shim (.035") was about 11 CC's. I figure that's ~ 5.5 CC's per .010" of gasket thickness so a compressed steel shim head gasket I believe is around .023", which puts the compressed volume at maybe 6 CC's. The calculated CR with the Fel-Pro gasket came in at 9.2:1 and with the steel shim I get 10.1:1.
Using the #1 intake cam lobe as a reference the .455" cam lift measured .462" at the retainer with a duration of 288 deg @ .004". The .509 measured a whopping .517" lift and 318 deg duration @ .004". I used a solid lifter and the appropriate push rod with a crane adjustable rocker set at zero lash to get the cam data.
Installed centerline on both cams came in at 109 deg with an Edelbrock roller chain in the straight up position. Advanced 4 deg and I got 105 CL.
I decided to go with the steel shim gaskets and the .455" cam. If I use the composition gaskets I would run the .445" cam advanced 4 deg to gain that bit of lost cylinder pressure.
