mderoy340
Well-Known Member
I've removed 3 sets of Mr Gasket thin head gaskets from 3 seperate motors and none of them have compressed to .028, all have mic to .032-.034
Need opinion
- Thread starter prostreeter9
- Start date
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prostreeter9
Well-Known Member
If I was to look at Pistons, do they make them that are taller? Is this a good option? Looks like the one that were stated before are just stock Pistons for a later model 318 is that correct?
Jon
Jon
nm9stheham
Well-Known Member
Very good to know. I wonder if they 'expand' at all when pressure is released. Going from .028 to .033 drops SCR in this case by about .09 points.
mderoy340
Well-Known Member
I'm no engineer but I don't think so. Every used fel pro 1008 is .039 as advertised.
nm9stheham
Well-Known Member
Yes they are, BUT removing the eyebrows is the key; it removes chamber volume roughly equal to a .030"-.040" cut on your closed chamber heads.
I am not aware of any lower cost cast pistons for the 318 that have a taller compression height. KB167's are a lot taller but I did not go there as the price is a bunch higher, and their lighter weight will push you to a re-balance of the crank. You might be able to finagle around the re-balance; I have not thought it through on possibility....
With KB167's, you'll be right around 8.9:1 with 65 cc combustion chambers, standard Felpro head gaskets at .051". The pistons tops will be around .012" below deck rather than .075" below deck.
And BTW, I have been assuming you have an LA block, not a Magnum block. Is this correct? The deck height is a bit lower on the Magnum block.
prostreeter9
Well-Known Member
Yes I have a 68 LA block. Also I've not picked up the heads yet been trying to decide about the shaving before I go get them.
nm9stheham
Well-Known Member
OK, then I used the right deck height for the numbers above. Again, the 65 cc chambers is an assumption.
nm9stheham
Well-Known Member
Thank you.
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