Heads cut for 94s but will 90.5 cyl work?

[Cave Man]

I know this has been talked about before but I can not find it. I have found a set of heads cut for 94's but mow engine runs 90.5's. Can I run these heads or will I be asking for certain trouble. They are him I cut with about 58 cc 40x35.5 stage 3 from Steve Sands at Pro Flow here in Ga. I haven't spoke to Steve yet but deal is on the table and I can't get him till Monday. What you think about running them like this.

[Dougzilla]

Tear it down and cut the case for 94's. Buy some
new 94mm P/C and you'll be happy and it will be
done right. A rebuilt engine with increased displacement.
Viola!

[Cave Man]

thats an option but didnt wont to go that route. like to run the 90.5s

[Ian Godfrey]

yes you can run the 90.5's as long as the chamber in the heads 'fits' with in the new bore size. Some 94 chambers use the full 94 diameter to unshroud the valve. This leaves the barrel with nothing to seat on.

[Bruce Tweddle]

It's called Power-sleeving.  You send your cylinders to RIMCO and they machine a collar to go around the tops of your cylinders with the same OD as 94s

[neil68]

You could also just sell your 90.5 piston kit, and then buy some 94 slip-ins...they will fit your 90.5 case and 94 heads.  I've been running this set-up for several years without issue

[dangerous]

You could also just sell your 90.5 piston kit, and then buy some 94 slip-ins...they will fit your 90.5 case and 94 heads.  I've been running this set-up for several years without issue

This only works if some one has incorrectly bored the case down to the bottom,
instead of correctly boring it for the 90.5 piston and cylinder at two diameters.

So long as the cylinder does not overlap the chamber too much
you can use your 90.5's, but it helps to have a locating sleeve or "power sleeve".
I have used the power sleeve method on 90.5's,
even with a chamber unshrouded to 92, and it worked well.