They do.

say what :boggle:

do those heads not have squish zones then?

i am


but thats not related

stem seals, gonig to remove the head and get the head pressure tested

It's nothing to worry about if you're not burning any oil.

There are lots of variables that effect the results of these tests.

done 56k



and when stripped look perfect tbh.....

Will be down to wear on the engine.

just seems although its down slighty


although nothing wrong with it, just woundering what has caused it and weather its right or not

as most are 30-40psi more

Compression test only measures how well a cylinder seals. To an extent it has an affect on performance. But it doesn't indicate true cylinder pressure. If you want to compare performance using cylinder pressures use BMEP.

Easiest way to work out compression ratio is to cc it.

And yes more compression does mean more power.

ttt

quote:

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Originally posted by Dave A
compression and compression ratio are 2 very different things, compression ratio can be massively affected by working the combustion areas on the head but compression itself wont be affected by more than a few PSI.

to measure cylinder compression leakage, use a leakdown tester. rather than getting a reading that is affected by compression ratio, you will get a reading of cylinder leakage which is a far more accurate measurement

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compression and compression ratio are 2 very different things, compression ratio can be massively affected by working the combustion areas on the head but compression itself wont be affected by more than a few PSI.

to measure cylinder compression leakage, use a leakdown tester. rather than getting a reading that is affected by compression ratio, you will get a reading of cylinder leakage which is a far more accurate measurement

say i did, what difference would it made

theres only two ways of raising it back up

but dont realy want to skim it again uptill it needs it

and im 100% not skimming the block! lol

yet i know sound one else who has a chamber polished and ported but he has 250psi :!

how much power difference would that make?

More compression will mean you may have to run high octane fuel though, and have it mapped to run that fuel.

You should have measured the chambers, and worked out the proper compression ratio.

quote:

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Originally posted by Vaux Lad
Did you measure the chambers before and after?

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quote:

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Originally posted by andyc1234
if its had combustion chamber done then yea it will be slighty lower. not sure if you wont notice it though without having a silly spec relying on high compression

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if its had combustion chamber done then yea it will be slighty lower. not sure if you wont notice it though without having a silly spec relying on high compression

Did you measure the chambers before and after?

lots of chamber work done

i meant in the combustion chamber




[Edited on 28-03-2008 by warren.g]

ported head shouldnt chage compression unless its had the chamber side worked on

most 1.6 x16xe's have (from what ihave tested) between 200-240 psi compression

my 1.4 had 190-200psi

now the 1.6 has 180-190 psi (due to the port and polished head??)

its already been skimmed, but is there alot more power available with another skim??