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Discussion Starter · #1 · (Edited)
A long story short my motor was built wrong the 1st time. Well not built wrong but milled improperly, which caused a blown hg. before my compression was 190 all the way across which is a bit to high, because of the block being milled wrong. So now i have to re mill the block so that it will be correct. so here is my question/problem. Rt now i have almost brand new CP 9:1 pistons and since the compression was so high if i re mill the block it wil be even higher due to the block being even closer to head. so i was wondering if it would be stupid or if it would even work to mill a tiny bit off the pistons to lower the overall compression. or if this is possible without altering the performance of the pistons.I know i could get a new block and start over but that would seem like a waste of money and i dont have the spec sheet for the pistons anymore. Any suggestions are appreciated. or any other possible ways to lower my compression.

thanks, brandon
 

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i made two passes over my block and 3 over the head when i milled my engine.

IIRC, we took about .008" total off (block + head). i'm running CP 9.0:1 pistons on my stroker and have no clearance issues. also have the TRD head gasket.

-Mike
 

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Discussion Starter · #10 ·
Isnt the TRD head gasket 1mm. I guess i could do that ^ but my comp was already at 190. I dont know if it was so high because of the improper milling or what but i dont really want to take the chance of putting it all back together and the comp be really high again. I think im gonna go with the TTE which is 1.4mm i think? which will help lower the comp a little. but i dont know if it will be enough.
 

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It should be fine. stock head gasket is only .8 mm. Soo if you go with a TTE 1.4 which is what I did that is almost double the thickness of the stock gasket. I doubt your going to be milling .6 mm from the block. I think you will ok as far as clearence issues go. Also should lower the compression a little but not that much. .6 mm of volume increase in the cylinder isn't that much. But it should be enough to get you back to 9.0 compression. just my thoughts, right josh?
 

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Discussion Starter · #12 ·
well the problem with my situation rt now is that the block is uneven. and some of the pistions are sticking up higher than the block/ when they are suppose to be level or lower. So if i make the deck even it will be even lower and logicaly it seem it would the pistons would been even higher
 

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turbolence56 said:
It should be fine. stock head gasket is only .8 mm. Soo if you go with a TTE 1.4 which is what I did that is almost double the thickness of the stock gasket. I doubt your going to be milling .6 mm from the block. I think you will ok as far as clearence issues go. Also should lower the compression a little but not that much. .6 mm of volume increase in the cylinder isn't that much. But it should be enough to get you back to 9.0 compression. just my thoughts, right josh?
correct -- using the thicker gasket is a easy way to drop CR and do it reliably

BTW -- mike -- ever get your car running yet?
 

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Brandon.. if you can visually see uneveness far as some pistons stick up higher than others.. imo that block is junk... anyway you try to correct it...its a bandaid to the situation, not to mention your head is uneven as well.. I think you should cut your lost and find a new block.
 

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Brandon,

If you know of a machine shop that can correct the block, offer a solution the compression problem, and guarantee you will not have a HG problem again, then go for it. If not, get another block.
 

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bmk said:
mister3 how would you go about doing this?
well -- we can mill the block true and mill the pistons to make it a zero deck height + we'd also inspect everything and most likely build a different block for you and assemble everything into it........ also a reason for 2 pistons sitting low could be bent rods.....
 
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