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Rb20Det Head

david69

By david69,
in Engines & Forced Induction

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david69 Community Regular

david69

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Surely there is a limit as too the maximum amount that the rb20det head can be skimmed.there must be a way to measure maybe a reference point on the top of the head to the block mating surface.i don't want to buy another unskimmed head as a reference, as that will tell me nothing other than mine is thinner.i just want to make sure im not gonna increase my compression ratio on my stock bottom end and damage anything.

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XRATED Veteran

XRATED

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At the end of the day, someone will have had to really hack into the thing for it to be considered 'too thin' to use. Not too many machinists would do that.

Rb20det comes from the factory with quite a low compression ratio as it is. A couple points more static CR is only a good thing.

When you put it back together, just be sure to get it on a dyno.

Cheers

J.

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StevenCJR31 Veteran

StevenCJR31

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Posted

At the end of the day, someone will have had to really hack into the thing for it to be considered 'too thin' to use. Not too many machinists would do that.

Rb20det comes from the factory with quite a low compression ratio as it is. A couple points more static CR is only a good thing.

When you put it back together, just be sure to get it on a dyno.

This ^ at 8:5 to 1 an increase in CR wont harm the motor

Cheers

J.

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GTSBoy Grand Master

GTSBoy

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Piggaz advice is 100% valid. Put the valves in with some grease around the seats to make sure they seal. Get the clear part of a CD case and drill a 5mm hole in the middle. Slap that on the head face with a smear of grease to seal it. Set the head so it's nice and level. Use a burette or even a syringe to measure how much water you put in through the hole. Even with rough set up and equipment you'll be able to find out to within a fraction of a CC what the volume is. Job done.

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