16V/20V pistons

[robokill]

if size (bore 81mm standard 81.5 first oversize etc) are the same I would not see why not.

[Ivan141]

woper: if I remember all the discussion about the compression ratios form the past, the general idea was that US cars have the 9.4:1, while euro low-comp-non cat was 10.0:1 ratio (at least for ae86's).
The 2 different partnumbers for the bluetop pistons seem to confirm this too.

We both got the comression ratio for ae92 smallport engines wrong though...it's not 10.0 or 10.9... its 10.3:1.

[oldeskewltoy]

[u:98f2b5eeb5]16V[/u:98f2b5eeb5]
US 4AGE early 9.4 to 1
euro 4AGE early 10 to 1
1990+ 4AGE 10.3 to 1

stock head gasket is 1.2mm. Each 1/10 of a mm is ABOUT 1/10 of a compression point. using .8mm gasket you get a .4 compression boost. The later 10.3 slugs, and .8mm gasket gives you an approximate CR of 10.7 to 1 Anything much over that will need a stand alone engine management to run at its best.

There is an advantage to running 16V high compression slugs... they are cast(with heat coating). They are MUCH lighter then the 20V pistons which are forged


Woper - from my info each piston has different rings... 20V rings are pretty much for 20V pistons.

[jamiemirror]

There is a catch with head gaskets. 1.2 uncompressed, ~1mm compressed. But MLS gaskets will compress less if any - so 0.8mm will not gain 0.4 CR, just ~0.2.

Early and late 16V engines use different piston rings.

[woper]

I guess I have to check it out, how the things are going with 4AGE pistons ))
I'll let U know, after I disassembly 20V bottom and 16V high compression.

Thanks for advices!