CRXFi Build Thread (Geo Metro XFi drivetrain in Honda CRX)

[bhazard]

Interesting hybrid swap, kinda the opposite as my b6t festiva, though many similarities.

The donor car for the b6t festiva swap (merc capri or mazda 323gt) is the same width as a festiva, so the axles are the correct length.
You also drop the whole b6t engine harness into the festiva, all the plugs for the engine are there, and goes straight to the ecu. You then run a few wires to ignition switch for the hot connections.

My best yet is 38.8 mpg, .3 better than the best I got in the donor car, and about 10 mpg lower than what I averaged in the stock festiva (lol). Still got some issues, like an exhaust manifold crack thats drawing in fresh air over the o2 sensor causing it to run rich. Im running o2-less for now. More engine and bigger tires, but its lowered a bit and I swapped a taller 5th gear in. Im hoping to maintain at least 40 mpg out of it in the end, and I expect a much bigger number out of this CRX.

[Christ]

Originally Posted by bhazard

Interesting hybrid swap, kinda the opposite as my b6t festiva, though many similarities.

The donor car for the b6t festiva swap (merc capri or mazda 323gt) is the same width as a festiva, so the axles are the correct length.
You also drop the whole b6t engine harness into the festiva, all the plugs for the engine are there, and goes straight to the ecu. You then run a few wires to ignition switch for the hot connections.

My best yet is 38.8 mpg, .3 better than the best I got in the donor car, and about 10 mpg lower than what I averaged in the stock festiva (lol). Still got some issues, like an exhaust manifold crack thats drawing in fresh air over the o2 sensor causing it to run rich. Im running o2-less for now. More engine and bigger tires, but its lowered a bit and I swapped a taller 5th gear in. Im hoping to maintain at least 40 mpg out of it in the end, and I expect a much bigger number out of this CRX.

Mid 50's average, mid 60's all highway. For the places Will travels for work, it'll be an excellent highway machine, and with great aero (surely to be further improved), there's no reason he couldn't get up to 65 highway, IMO.

I'm interested to see how close my anticipatory guess is.

[MetroMPG]

Just catching up...

Originally Posted by Wonderboy

Could someone here (Darin?) with a Mk3 measure the distance between CV boots?

Do you still need this measurement? What's the Mk3 again? Speak in years to me.

Does anyone here have (access to) a 1.3l mk3?

For measurements? If mk3 = 95-01, I know where there's one about 25 km from here. I've been meaning to go out there and ask them if they were available. (Despite having far too many projects already.)

[MetroMPG]

PS- congrats on the maiden voyage (axle notwithstanding)!

It's still rough, but better than it was when I first set out.

If it feels like it's only running on 3 cylinders... then it's perfect!

[texanidiot25]

If you're still having coolant issues, I recall my dad (ASE & GM master tech) mentioning that bypassing the heater core can sometimes cause funny coolant problems. If I recall right, it's since there's now less capacity for coolant that it causes problems. Heater hoses are easy to adapt from car-to-car, just a matter of getting it from one pipe to another usually, no fittings to mess with on these older cars.

[Gasoline Fumes]

I don't know how official this is, but this is how the years are usually broken down on TeamSwift. This only applies to cars sold in North America.

MK1 = 1985-1988 (Chevy Sprint in the US)
MK2 = 1989-1991 ("square" dash, rear license plate between taillights)
MK3 = 1992-1994 ("round" dash, rear license plate in bumper)
MK4 = 1995-1997 ("new" body style)
MK5 = 1998-2001 (sometimes included in MK4)


Which axle from the 1.3L are you thinking of using? The passenger's side axle is a two-piece unit that can't be used on a 3-cyl engine.

[Wonderboy]

Yahooo!!!! I can't believe it! I measured my custom axle at about 16in from boot to boot. I went to the junkyard and measured the axle from the MK4 (my mistake, it was not an mk3, it was one of those "guppy mouth" bumpers with convex headlamps) and it turned out being far too long (wasted an hour and a half battling with stripped bolts and didn't end up recovering the axle). Lucky me though, I walked up to a 1.0l mk2 (same style as my xfi - convex headlamps) automatic, measured between the boots, and wouldn't you know it was ~16in. It has a doo-dad on it right next to the hub-side boot that rubs on my suspension fork (whatever it's called) when I turn the wheel a certain amount to the right. It makes an awful sound and will need to be removed or ground down a bit. It looks like this, except the doodad on mine is on the hub side, not the trans side:

Anyone know what that doo-dad is even for?...Anyway, I don't have to make custom axles ever again! I took it on a better maiden voyage up a steady, gradual 3 mile climb up to my parents house then back down. Beginning up the hill it would hesitate every so often, and it took a bit of a battle to even make it to the bottom of the hill, as I stalled it a couple of times getting through a bunch of traffic lights and experimenting with turning the headlights on. Getting near the top of the hill it hesitated less and less. I engine braked as much as I could on the way down, and it felt noticeably better driving around in the city, stopping and going. I stuck a meat thermometer into the rad fins but the reading didn't go over 120 I think, which was surprisingly low to me - thought it would be hotter after a big climb. The cluster temp gauge stays below center. I'm still not sure how accurate it is since the gauge is Honda and the sensor is geo... Like Gasoline Fumes was mentioning earlier in the thread it's all probably Nippon Denso, but I still don't know if there may be a difference in resistance between the Honda and Geo temp sensors that would cause an erroneous display. I'm starting to trust it more though after that big climb. Starting off in 1st gear is a lot smoother now, but could still get better. It sounds quiet idling from the outside, but it sounds like a freakin' army jeep from the inside with a lot of the dashboard supports not put back in yet. Should I take the oil out now and filter it / replace it outright yet, or should I wait until more break-in occurs?
I left the tube off of my air filter... Anyone foresee that being a problem, or should I just leave it there for a WAI? I've heard metros don't like HOT air, but I haven't heard anything about warm. I'm wary of going WOT under any kind of load yet... how long should I wait for that? This is exciting, I feel so proud driving that noisy thing around (the exhaust is not totally sealed either - that will need minor repairs as well.)

Originally Posted by Christ

For the places Will travels for work, it'll be an excellent highway machine, and with great aero (surely to be further improved), there's no reason he couldn't get up to 65 highway, IMO.

I actually got a pretty sweet 9-5 job now that I walk or bike to every day only about 6 blocks. This car will be a gas powered umbrella, stuff-mover, and "wtf is he driving?" eye catcher for now until I get the electric umbrella-and-stuff-mover working

Originally Posted by MetroMPG

If it feels like it's only running on 3 cylinders... then it's perfect!

Yes it DEFINITELY feels like 3 cylinders. Much weaker accel. on the high end than I'm used to, but that's what I was wanting to sacrifice anyway. I'll just spend a little more time in 4th gear, and relish my time in 5th gear cruising along at 55mph at like 1000 rpm

[Christ]

Originally Posted by Wonderboy

Yahooo!!!! I can't believe it! I measured my custom axle at about 16in from boot to boot. I went to the junkyard and measured the axle from the MK4 (my mistake, it was not an mk3, it was one of those "guppy mouth" bumpers with convex headlamps) and it turned out being far too long (wasted an hour and a half battling with stripped bolts and didn't end up recovering the axle). Lucky me though, I walked up to a 1.0l mk2 (same style as my xfi - convex headlamps) automatic, measured between the boots, and wouldn't you know it was ~16in. It has a doo-dad on it right next to the hub-side boot that rubs on my suspension fork (whatever it's called) when I turn the wheel a certain amount to the right. It makes an awful sound and will need to be removed or ground down a bit. It looks like this, except the doodad on mine is on the hub side, not the trans side:

Anyone know what that doo-dad is even for?...Anyway, I don't have to make custom axles ever again! I took it on a better maiden voyage up a steady, gradual 3 mile climb up to my parents house then back down. Beginning up the hill it would hesitate every so often, and it took a bit of a battle to even make it to the bottom of the hill, as I stalled it a couple of times getting through a bunch of traffic lights and experimenting with turning the headlights on. Getting near the top of the hill it hesitated less and less. I engine braked as much as I could on the way down, and it felt noticeably better driving around in the city, stopping and going. I stuck a meat thermometer into the rad fins but the reading didn't go over 120 I think, which was surprisingly low to me - thought it would be hotter after a big climb. The cluster temp gauge stays below center. I'm still not sure how accurate it is since the gauge is Honda and the sensor is geo... Like Gasoline Fumes was mentioning earlier in the thread it's all probably Nippon Denso, but I still don't know if there may be a difference in resistance between the Honda and Geo temp sensors that would cause an erroneous display. I'm starting to trust it more though after that big climb. Starting off in 1st gear is a lot smoother now, but could still get better. It sounds quiet idling from the outside, but it sounds like a freakin' army jeep from the inside with a lot of the dashboard supports not put back in yet. Should I take the oil out now and filter it / replace it outright yet, or should I wait until more break-in occurs?
I left the tube off of my air filter... Anyone foresee that being a problem, or should I just leave it there for a WAI? I've heard metros don't like HOT air, but I haven't heard anything about warm. I'm wary of going WOT under any kind of load yet... how long should I wait for that? This is exciting, I feel so proud driving that noisy thing around (the exhaust is not totally sealed either - that will need minor repairs as well.)


I actually got a pretty sweet 9-5 job now that I walk or bike to every day only about 6 blocks. This car will be a gas powered umbrella, stuff-mover, and "wtf is he driving?" eye catcher for now until I get the electric umbrella-and-stuff-mover working

That donut is a vibration damper. You can mostly remove it if you need to. I used to take them off my CRX/Civic axles to save weight. (~2 lbs, IIRC)

Good job on the... umm... job.

When you get the electric umbrella-and-stuff-mover working, let me know. Maybe I'll be interested in (and rich enough) buying the CR-XFi from you, if you want to sell it.

I'm not sure how likely it will be that I'll actually have the money, but still... let me know if you decide to sell it.

[Gasoline Fumes]

I think I still have the auto axle from my '94 Metro if you want it for a spare. No charge. I knew they were different lengths than the manual axles, but I never realized the difference was anything significant. And I agree with Christ, just take the damper off.

I think your interior noise is coming from your engine mounts. All that 3-cyl vibration is going right to the body. And probably stressing those welds....

I don't know if the radiator fins will give you an accurate temp reading. An aftermarket gauge with real numbers might be nice to have. Is your heater circuit looped or capped off? I've heard a loop can make the coolant bypass the radiator and cause overheating. This was on a Swift GTi race car, but the cooling system is basically the same.

[Wonderboy]

Originally Posted by Gasoline Fumes

I've heard a loop can make the coolant bypass the radiator and cause overheating.

Ruh-roh. I'd better try to get those heater bits in this weekend when blowers are on sale at the junkyard.

Originally Posted by Gasoline Fumes

I think I still have the auto axle from my '94 Metro if you want it for a spare.

Awe golly, thanks! That's really nice. I'll be glad to pay it back or forward. Meet me in Syracuse this Friday? (I'm only half joking because I'll actually be there) I'll get you some grub. I won't have the CRXFi though because I'll be going to get more than 1 passenger. Maybe I'll try to finagle my own rear seating for the rex.. hmmm....

Originally Posted by Gasoline Fumes

I think your interior noise is coming from your engine mounts. All that 3-cyl vibration is going right to the body. And probably stressing those welds....

You don't scare me. Yet...