Conversion - lsi convertible into xfi convertible

I've been doing a 70 mile daily commute and even with my 1991 lsi convertible's top notch gas mileage (46 mpg average) I'd like to get even more fuel economy. I know the xfi gets mileage into the upper 50s. What would it take to convert my lsi into an xfi? I know the xfi uses a different cam, gears, and ecm. Are these parts plug and play into the lsi? I need to do at least 60-65 on the expressway to be safe.

Thanks

the tranny in your vert has 4.39 gears, the xfi has 3.89 so with the 13" tires you will lose some power on the bottom end

I don't think finding the 12" rims and tires would be all that much of a challenge. I suppose my biggest concern would be having to do any modification of the wiring harness. I once put a chevy v6 into a Suzuki Samurai and the wiring on that never worked out to my satisfaction and I eventually gave up on the project.

The lsi to xfi conversion sounds more straight forward. As far as losing power on the bottom end, I'm rarely in a situation where I need rapid acceleration. I just need to be able to keep up with some of the slower traffic. I have a source on the xfi parts I need and they might have the 12" rims as well.

i think the xfi also has 2 ring pistons as compare to 3 ring ones in the normal metro. you could just put the xfi tranny in with the xfi computer, wiring should be the same. not sure your gonna get much better mileage though. xfi only got about 52 max and your vert is heavier

Yep, I hadn't thought of that. The convertible is heavier. I keep forgetting about all the bracing and extra metal needed to make the metro convertible. I'll just have to settle with 46 mpg then.

Thanks

i think the xfi also has 2 ring pistons as compare to 3 ring ones in the normal metro. you could just put the xfi tranny in with the xfi computer, wiring should be the same. not sure your gonna get much better mileage though. xfi only got about 52 max and your vert is heavier

Hi all,
I just went through the 3 day project of changing my 1994 geo metro auto to an xfi, It was a little more involved than I thought. I had to change out pedal assemblies (a real knuckle cutter, also drill hole for clutch cable, also drill holes for the transmission mount. Also had to short two main wires on the neutral safety switch harness and find the two wires for the backup lights and splice them in with the switch on the standard tranny. After it is all said and done I have been keeping track of my gas mileage. I drive 90 mile round trip a day to work. I am getting a solid 51- 52 miles a gallon going 65- 70, I do have one question for anybody that might know. Is the timing setting different on an xfi metro?? The car was originally an automatic. I changed motor and all. The auto says under the hood that the timing should be set at 5 btdc, I was contemplating setting it a little higher to see if I can get the 53 cty, and 58 hwy window sticker mileage. Oh and if anybody wants an automatic 1.0 53k original miles I have it also the auto tranny and various other odds and end parts. Just email me and let me know. Thanks in advance.