European Piston Question

[economycar]

I am in the US and I am doing a mild rebuild on a large port 4age with 18mm wrist pins. I have heard that there was a large-port motor in the EU which had a 10:1 or 10.2:1 compression ratio with 18mm wrist pins. Is this true? Does anyone have part numbers? I have heard that there was a Finnish spec motor, could this be the one?

Any info would be appreciated, I don't want to buy custom pistons but I want more than the stock 9.4:1 without cutting the head or the block too much.

Thanks,
Mike

[Ivan141]

Yeah that is something we're a bit uncertain of ourselves over here.. lots of spec sheets seem to indicate a 10:1 CR for early model 4age's, and there seems to be a difference between the pistons in pictures said to be from a US 4age and those of euro 4age's. The number of different partnr's for stock bore 18mm wristpin pistons is also a possible indicator.

That being said, Why not go for custom pistons? I doubt toyota sells pistons way cheaper than Wiseco does (450-500USD?), so it might be interesting to opt for 11:0 wiseco's in stead of using hard to find toyota pistons (Toyota US probably doesnt stock these pistons).

[jamiemirror]

http://cgi.ebay.com/ebaymotors/ws/eBayIS...558&rd=1,1

Higher
vs
lower

http://cgi.ebay.com/ebaymotors/ws/eBayIS...182&rd=1,1

CR piston for 18mm pin. Stock (but not original as you can see).

[Ivan141]

Just had a look-see at my old bluetop pistons, they are marked 16030, which should correspond to the last numbers of the ordercode. The center is raised slightly above the outer edge of the piston on those. The redtop pistons have a more pronounced rise in the middle.

[peter møller]

Yup....redtop pistons look nothing like the ones linked to on ebay The middle is allmost "flush" with the piston outer diameter, the look completly flat, only with the depths to make room for the valves.

[jamiemirror]

Guys, I listed only 18mm pin pistons. Smallport ones use 20mm pin.

[oldeskewltoy]

Well I've done some research going through the EPC. What I've found is that there is indeed a # different for parts of "EUG and Singapore" that got piston# 16030. The USA AW11 MR2 uses 16020... that is the same piston as the "FRG" and "4AGEC" spec piston.

So in essence there are 2 different bluetop pistons... 16020 is the 9.4 CR of the USA and a few other places that used the 9.4 to 1 CR. The 16030 pistons would be the "other" one.......

[gon]

yep , they are 10:1
i will sell you my 10:1 18mm pin if you want altough they have 150k miles on them .... but they still look good