The Stovebolt Site Forums The Shop Area Engine Shop 235 rebuild - sleeve or .080 overbore?

With Chevy 235 becoming increasingly difficult
to find, I buy them when a chance comes along.

I bought one, 55 - 57 casting, and brought it
home from San Pedro with crossed fingers. Not
too bad except one cylinder presents a challenge.

The previous owner allowed water to enter the carb
which ended up in the number one cylinder causing
very minor rust damage. This damage, although
minor, is measured at .012 to .015 in depth.

Real problem is this engine is stamped bored to
.040 and normal limit is .060 overbore. Taking
it out to .060 will not quite clean out all of
the damage, minimal left but that is unacceptable.

I am told you can take the 235 out to .080 over
like the big brothers. However, over the decades,
this has never been my personal practice. I am
concerned the water jacket will be too thin which
will cause overheating problems.

My first choice is to sleeve all cylinders and
bore to standard. This will present no problems.

Still, I am curious about a .080 overbore with
a 235 cubic inch (not the larger engines) and
what effects where noted.

Anyone have any direct experience with this?
Positive or negative outcome?

Thanks,

Billyray

I have built several .080 over 235s one built quite radical. None have had any problems.

Thanks Dave. Heat is not usually a problem with
the 235 engines. I run "desert" radiators which
is just a fancy term for 4 core radiators.

Compression and breath draw will be slightly
greater but I don't think will be a problem.
Stock compression is very low to begin with.

Dave, do you have a favorite parts source for
those .080 pistons and rings?

Thanks,

Billyray

I get most of my parts from Northern Auto Parts. www.northernautoparts.com

My usual parts source is Internal Engine Parts Warehouse, in Nashville, TN. I think their corporate headquarters is in Mississippi, and they distribute parts all over the southeast. Good people, and they have a good jobber's discount.

Doing a full sleeve job will be expensive, unless you've got your own boring equipment. I salvage trashed-out 4-bolt main bearing 350's that way, and run them in round track cars at over 600 HP in some applications. Some of my competitors GIVE me blocks they think are junk, and I recycle them and beat them with their own scrap iron! 80 over on a 235 shouldn't be a problem, however; those blocks have a lot of iron in them!
Jerry