ive noticed they come in 2 diff thicknesses ?

how come ?

matt

 

So you have more choice on the CR.

 

so is it just the std thickness one you need if you wanted it same as ?

 

yep, if you want to keep your cr as it is (which will typically be higher than std as most heads have now been skimmed) then just get the standard one.

There are more than 2 thicknesses available for most engines, altohugh ive only used standard on a YB so cant confirm the options for that, but on the vauxhall engines they do 3 or 4, including one thats thinner than standard.

 

does using a thicker one not ruin squish?

 

I wouldnt go as far as "ruin" but it certainly makes it marginally worse.