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Comp ratio suggestions please

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Old 30-01-2013, 11:56 AM
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ram
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Default Comp ratio suggestions please

Hi guys

currently rebuilding my engine and need to send the pistons off for cut outs and possibly ratio change. my previous set up was running 7.5-1, but this was with C.P pistons, i'll now be running 4x4 Mahles.

spec will be..

200 block
2wd head with normal headgasket
standard rods
Mahle 4x4 pistons with cut outs
BD14
T38 around 30psi

Wondering if 7.5-1 is too low really? i have a feeling i once read that 4x4 pistons and 2wd head drops the ratio to 7.8-1 anyway? so if thats the case i guess i just go for pockets and leave ratio as it is.

Cheers

Last edited by ram; 30-01-2013 at 12:05 PM.
Old 30-01-2013, 12:04 PM
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Bart
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I would do just cut outs and keep the c/r as high as possible.
Old 30-01-2013, 11:51 PM
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ram
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Thanks yeh so long as the ratio is 7.8-1 with my head and piston set up then i'll leave the skimming. just need someone to confirm that really
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