i have my pistons at the machinist's shop and i have to decide how much to take off the top and de-lip them to achieve the 16.5:1 or 16:1 comp ratio; what do you guys think needs to be done? i have to let him know in the morning
cut lb7 pistons????
- Thread starter dmaxvaz
- Start date
16.5 would be fine wouldnt it for lets say 650-700hp? would just de-lipping do this?
If you are or ever plan to be going bigger on the cam you should have the valve reliefs cut now. That and delip will get you where you want to be.
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no bigger cam at this time
how much off the top is necessary? i am not going big on this build so the reliefs are not needed
What pistons are you using, what rods are you running, I would do assemble and check deck height and see how far out the hole you are know.
Yes, I take off ten thou so:
I can run Crower rods which are .004" longer.
I can plate the pistons .002"
I can run the thin gaskets.
If I do none of the above, I still have a tight squeeze area to help combustion.
Guy has a spreadsheet that tells what the different cuts do to compression. I think he posted it here.
I can run Crower rods which are .004" longer.
I can plate the pistons .002"
I can run the thin gaskets.
If I do none of the above, I still have a tight squeeze area to help combustion.
Guy has a spreadsheet that tells what the different cuts do to compression. I think he posted it here.
I'm standard bore and 0 deck height and run grade c head gaskets and I think it came out to be 16.3 to 1, Not sure how much Guy took off.I want to say .010 or.015
See post #6 in here. That might help you
http://www.duramaxdiesels.com/forum/showthread.php?p=184815&highlight=gasket#post184815
See post #6 in here. That might help you
http://www.duramaxdiesels.com/forum/showthread.php?p=184815&highlight=gasket#post184815
thanks kat, for some reason i cannot open the file
Just delip and radius. That will get you to 16.25. You will need to mock everything to figure out which gasket you really need. Dont just throw in C gaskets. Find out what gasket you really need.
Mine have a .1875R also. I put .125 on pistons without valve cuts to help with compression. Piston with valve cuts get .1875. Either should work dandy.
