[DeTomaso] 383 vs 393 vs 408 ??

[JDeRyke at aol.com]

In a message dated 2/19/10 3:14:42 PM, erik at unicall.no writes:

> The only sensible thing to do is to keep the original cylinder block and 
> fit the rest new after boring it to .040". It is already .030". To fit new 
> complete cylinder heads and maybe a stroke kit from Scat(?), will probably 
> do?!   The car need 400-450 hp(DIN:-), with good torque!
> 
NO!!! Before you even THINK about rebuilding this engine, sonic-test the 
cylinder walls for thickness! Cleveland engines are notorious for shifted 
cylinders during the factory casting phase. I've seen quite a few UNBORED blocks 
that failed the wall thickness test- some were below 0.100" thickness 
stock. Boring such a block will yield paper-thin cylinder walls that won't seat 
rings nor hold compression, and will eventually blow up. Adding a stroker 
crank will make a thinwall block even worse. 
I have a friend that should have known better but had his Pantera's block 
bored 0.040"-over without checking thickness, and a year later, the engine 
was still blowing oil out the breathers. The paper-thin cylinder walls balloon 
under stock combustion pressure, bypassing huge amounts of oil past the 
rings- 1 qt per 200 miles. He eventually gave up, threw the block AND pistons 
away and started over with a different block that sonic-tested OK. Very 
expensive lesson.
Second point: if you find a block that has only small wear marks up in the 
top of the cylinders, its OK to HONE the cylinders straight, up to 0.004" 
oversize, and use 4.000" FORGED pistons that expand under heat a little more 
than cast pistons and are much stronger. This much honing may not remove 100% 
of the wear areas, but you'll find that the worst wear is normally above 
the ring travel, so boring to remove it only makes the combustion area larger, 
with no benefits.
My block wall-checked OK, but was honed 0.004" oversize, runs 4.000" forged 
TRW pistons and std. 4" rings, and still puts out good power with almost no 
oil use, after 17 years of track and street driving in a Pantera. Good luck 
on your brother's engine- J DeRyke