2.2 motor question

[914/6now911]

I am looking at a motor for sale, advertised as a 2.2L. However, the seller says it has a '73, 2.4L case, with 2.2 pist/cyl. Can that be?

[Tyson Schmidt]

Then it is a high compression 2.4 l. The 2.2 and 2.4 had the same bore but different strokes. The 2.2 liter engines had higher compression pistons which when installed in the longer stroke engine, become .55 points higher yet.

Are they T,E or S pistons and cylinders?

Also, which crank? The 66mm, or the 70.4 mm? The number on the case doesn't necessarily reflect what is now inside.

But my guess is that someone installed 2.2 P's and C's on a 2.4 liter bottom end to get a high compression 2.4 liter. That's a pretty common mod.

[914/6now911]

Tyson,

Thanks for the reply. I didn't realize the 2.2 and 2.4 had the same bore. The seller doesn't have much info, but your data helps. I now know what specifics to ask. It sounds like I definitely need to find out what the ultimate compression ratio is; don't want something crazy high trying to run on pump gas.

[Tyson Schmidt]

Well, it shouldn't be too high for pump gas. 2.2S pistons in a 2.4 will yield a theoretical 10.35/1 CR. But bruce Anderson states in his book that if you build this motor, it actually comes out around 9.6/1 for whatever reason. So even in the most extreme case, you should be fine on pump gas if you run Super.

[Wayne 962]

Right - about 9.6:1 is about right. This is a good recommended upgrade (as referenced in the new book)...

-Wayne