head gaskets/milling heads
08-09-2010, 09:42 PM
#21
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well your going to aftermarket pistons. thats not stock bottom end...
you need to measure how far pistons are in the hole, find out want cc the valve reliefs are in the pistons, the combustion chamber size... then your cam specs.. then find a compression calculator...
or someone that has built a .040 over lt1 that used the same pistons as you might know... i'm not to sure you can hit that compression and get in the quench range with a flattop piston unless it only has 2 valve reliefs..
you can do it milling the heads, but as 95ramairta also stated thats not actually the correct way to obtain the compression you want.. i think you would be better off decking the block about .015 rather than milling the heads..
you need to measure how far pistons are in the hole, find out want cc the valve reliefs are in the pistons, the combustion chamber size... then your cam specs.. then find a compression calculator...
or someone that has built a .040 over lt1 that used the same pistons as you might know... i'm not to sure you can hit that compression and get in the quench range with a flattop piston unless it only has 2 valve reliefs..
you can do it milling the heads, but as 95ramairta also stated thats not actually the correct way to obtain the compression you want.. i think you would be better off decking the block about .015 rather than milling the heads..
08-09-2010, 11:25 PM
#22
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I may go 353 if i can, than i can keep the chamber smaller, deck the block .010 and mill the .010 heads to clean things up, run the impy gasket, find proper pistons.
That way both my block and heads will be cleaned up well, Ill run the impy gasket or somehting similar depending on the engine builders piston choice. So then we can figure out what the combustion chamber size will be, use whatever gasket necessary to get my desired compression ration.
I know i am missing a few things as my bottom end motor build knowledge is not the best. any corrections would be appreciated.
That way both my block and heads will be cleaned up well, Ill run the impy gasket or somehting similar depending on the engine builders piston choice. So then we can figure out what the combustion chamber size will be, use whatever gasket necessary to get my desired compression ration.
I know i am missing a few things as my bottom end motor build knowledge is not the best. any corrections would be appreciated.
08-10-2010, 12:42 PM
#24
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If you have it apart have the machinist measure everything and then pick a good quench...(IMO for SBC/LT1 engines TIGHT QUENCH is good quench) and then have the machinist deck the block.
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
08-10-2010, 01:24 PM
#25
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If you have it apart have the machinist measure everything and then pick a good quench...(IMO for SBC/LT1 engines TIGHT QUENCH is good quench) and then have the machinist deck the block.
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
i have always shot for .035 to .040 quench on gen1 smallblocks..
08-10-2010, 01:57 PM
#26
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If you have it apart have the machinist measure everything and then pick a good quench...(IMO for SBC/LT1 engines TIGHT QUENCH is good quench) and then have the machinist deck the block.
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
For example I'm running a .027 cometic gasket....and pistons are .005 in the hole.... .032
with my flattop pistons and chamber size I'm a little over 12.1:1 and it runs good on pump gas...
Mike
Thanks, much easier to understand now.
