Gt4 Thin Cylinder Wall

January 19, 2005

I have heard that the early 94 GT4's have thin cylinder walls, and djdna2000 has just told me this aswell, i have a Celica GT4 ST205 WRC (Homolagation model) 1994

would this have the thin cylinder walls, could some one help me out here.. cos if so.. im gunna have to get a different block before i mod up my engine (BUMMER)

:unsure: :help:

January 20, 2005

I have heard that the early 94 GT4's have thin cylinder walls, and djdna2000 has just told me this aswell, i have a Celica GT4 ST205 WRC (Homolagation model) 1994
would this have the thin cylinder walls, could some one help me out here.. cos if so.. im gunna have to get a different block before i mod up my engine (BUMMER)

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As far as i know the only way to find out is to strip the engine down and get a density test done on the cylinder wall's as not all early 3s-gte's had this problem, from memory i think it is number 2 that has the fault and Toyota won't admit their is a problem btw <_<

Also i seem to remember Fensport did some research on this but my memory is a bit sketchy about it, so if i remember rightly you have a good un if the density is about 160,000 on number 2 wall and on a bad un if it is about 50,000 but i'm sure someone will be along to post the correct figure's shortly ;)

Personally i'd just mod it but keep saved up enough pennies for a block just incase you did need it.

January 20, 2005

As above, you can't tell without ultrasound really. It cracks between 2 and 3. I'm almost certain that a '94 WRC will have the 'thinwall' block.

Don't sweat it though, it just isn't a good idea to overbore too much, and stresses the requirement for good tuning!

January 20, 2005

As above, you can't tell without ultrasound really. It cracks between 2 and 3. I'm almost certain that a '94 WRC will have the 'thinwall' block.
Don't sweat it though, it just isn't a good idea to overbore too much, and stresses the requirement for good tuning!
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Some 94 WRC's will have the thinwall block as will some 94 rev3 MR2's but getting a new block won't cure the problem as some of the newer block's have a problem, just ask Tony & Dawesy who both chucked one on number 2 with a new block with forged piston's :o

January 21, 2005

as long as you dont go beyond 86.5 mm then you should be ok upto about 2.5 bar boost. these thinwall blocks are still ok for tuning but not for stroker kits.

around '96 is a safe year for the thick wall.

remember if you use a brand new block then you will have to 'season' it.

this means run in as normal and then std boost for 5000 miles to get enough heat cycles into it.