Metro XFI Score!
 

I found a Geo Metro engine on craigslist. I found out it was from a '91 XFI and I went to get it. I got the engine, transmission, axles, radiator, ECU, fuel tank and a bunch of various little parts. All for $100!!! I have yet to verify if it really is an XFI, but I'm happy either way for the price.

It's supposed to be a good running engine, but I haven't heard it run. I was going to rebuild my late '94 engine, but now I'm not sure. I could rebuild the XFI engine or rebuild the non-XFI engine and just stick the XFI cam in it. Anybody know if the XFI piston rings are the same as the normal engine's top rings? Or is it a special design?

They just leave one of the rings out for friction purposes I believe. If I were rebuilding an engine, I would find some Total-seal rings (better compression) to put in there, JohnnyMullet would know about the number of rings.

No, it's a different, XFi-specific piston. Not just a regular one with one ring left off.

That said, I'm not sure if it's the same ring as the non-XFi. When you find out, please post back though.

And... congrats on finding the $100 parts pile!

I would rebuild the non XFi, and then put the XFi cam w/ a +4 cam gear and ECU on it. Should do about as good as the XFi.

What, and give up the massive fuel economy benefit of the 2-ring XFi pistons???

I just read some reviews on the Total Seal rings and some people have had problems with them, while others love them. I don't think they're worth the risk. And they're not cheap either. $126 from Jegs. I got my NPR rings on eBay for $22.

I probably won't be using the XFI ECU. I'd have to basically convert the whole 1994 Metro to a 1991 and I think I'd lose the ability to use my Suzuki scan tool with the older ECU. What does the XFI ECU do differently anyway?

Taking a closer look at the engine, I see it's a '92, not '91. Which means I should be able to use the XFI ECU with my scan tool. Now I need to measure that cam. Wish me luck! :)

Do you mean measure the lift/duration?

Yep, lobe height/lift is shorter on the XFi.

Hope it turns out to be the lucky cam.

The ECU runs leaner on the XFI, and the tall gears are a big help, too. You can probably measure the cam right through the oil filler using the depth guage on a caliper, close enough for identification.