08 Honda Fit ECO gearing swap
 

Im posting a link that might be of interest to some, this is based off the 08 gearbox but I also have an 09 tranny in the mix as well

I will be swapping VX style gearing but a 5th gear swap will be possible as well should be interesting to boosted cars as well as the Ecomodder type

https://ecomodder.com/forum/showthre...wap-36618.html

It is possible to use the gears out of the 03-05 Civic Hybrid for sure inside the 1st gen Fit and pretty sure it will also work in gen 2. Gears 1,2,3 are the same while 4-5 are longer in the Civic. Final Drive is 3.6-1 vs 4.3 in the Fit. While I swapped all of the gears, swapping 4 and or 5 or just the FD should be possible
https://cimg6.ibsrv.net/gimg/www.fit...3082355bd4.png

Very interesting! Did you swap the entire transmission, minus the clutch housing, or swap out internals? Your post on the eco board says you swapped out the entire transmission I believe?

I mostly wish there was a better first gear option. It's too steep. Something in the 2.95 area would have it much more useful and not drop out of vtec on the 1-2 shift.

This is a motor swap INTO an Insight so I started with zero transmissions. I basically just took the Civic trans and swapped on the Fit bellhousing as my Fit donor trans was cracked elsewhere and cheap but you could just as easily just take the Civic guts and put them all in the Fit case. axle seals are all the same.

Cool! Thanks for that info!

So, I'm not positive we can jump to the conclusion that the Civic transmission Fit's in the Fit or that the Civic internals are a direct swap into the Fit's transmission since neither were done. All we know for sure is that the Fit bellhousing bolts to the Civic transmission.

Certainly sounds likely that they are interchangeable though! As long as there aren't mounting point differences or some weird internal difference.

How common are those transmissions? I wouldn't think very many manual Civic Hybrids were made?

The clutch case, bellhousing is part of the trans case it doesn't attach. I started this with two complete transmissions and compared all the parts, there is no doubt you can swap either gearset into either case, or like I did used one of each side. I couldn't find any differences on the outer case.
https://cimg4.ibsrv.net/gimg/www.fit...70c3462c0.jpeg

Thanks! Looking forward to hearing driving impressions. I know that's a bit away, but will be interesting.

Any idea of the weight of an L15 swapped Insight? I'm guessing you'll have a weight and aerodynamics advantage over a Fit to help with the taller gearing. In the world of Honda hatchbacks, the Fit isn't so light.

Not sure the number of manual HCH transmissions are out there but there were two at the yard I went to, I can't imagine the original owners hammered on them and the cars are all dying due to the aged hybrid systems i think they will be around for a while.

Fit engine is 30 pounds lighter if you count the battery and IMA motor although Im adding 100 pounds of audio

https://honda-tech.com/forums/honda-...muter-3290050/

Just googling the weight and adding 70 lbs net shows your Insight will be more than 500 lbs lighter than a Fit. It should do well with the taller gearing. Not sure that a Fit would since it has 25% more weight to move around.

Yeah, I think the only guys interested are turbo guy, the eco guys are all about this and its for sure not for most Fit guys. I do think people might be interested in just a 5th gear swap and this is a big clue that it will work..

After reading our conversation I should go on record to say that this is a horrible idea for 90% of Fit owners if not more, it's just info .... when the car is running I will for sure update this as well

I'm working toward a turbo install on ours. Have tons of parts here including a Quaife differential, billet flywheel, clutch, etc. I just placed an order for a ton of bearings and seals for the transmission and was really tempted to order the Civic final drive set. Is about $170 new. Just wasn't positive I want it even with the turbo. Keeping it as a maybe. I won't really know until I'm driving the completed build.

Let me see if I have got this right, you are going to end up with a 1st gen Insight with a 1st gen Fit motor and a Civic Hybrid transmission?

That sounds awesome and a heck of a lot of fun. Especially if that comes together without needing custom mounts, ie it all bolts together, one could almost make the argument that you should buy crapped-out Insights just to do this.

Will be so, so, hilarious if you are able to better the original car fuel-economy wise after this. I would say your chances are actually OK at that, and you'll end up with something faster than a Fit for sure. I have driven the Hybrid MT at length and it was fun (if slow) stock. Great quality transmission btw.

correct, it will also be turbocharged and I will have a smaller tire that the Fit/Civic as well just to be technical but yes

I did have to make mounts although the trans mount did line up so perfectly that the crank pulley bolt lined up with its little access hole and did have custom axles made. It will also be running Kpro and standard throttle body.

Funny note as steep as the Civic gears are the OE Insight 5 speed is even steeper for much less power available.

Yep, good call on the tires. They would be too big, although having done that inadvertently once I can say it's not totally disastrous.
Need Kpro because it will be turbocharged? Otherwise I assume stock Fit ECU would work?
I'm not surprised about the insight gearing ... yes much less power but the car was far lighter and arguably the customer would tolerate the slowness better. I can tell you this for sure: The Civic Hybrid 5MT was slow, borderline dangerous getting onto highways in rural areas. Albeit you will not need to worry about this, I forget total system HP of the IMA system but I think it was somewhere around 100hp so the Fit powertrain and 500lb savings will be fine .. to say nothing of a turbo ... what is point of turbo btw? (I assumed this was an eco build but now I am rethinking the goal!)

KPro because..... a wiring harness adapter is made for the chassis to ECU, E85 sensor, i like the idea of split injectors for bi-fuel future (Im into CNG) and all the flexibility the Kpro has over the factory stuff. I am also building a custom intake manifold to throttle body is not a big issue.

My goal is to have a car that CAN get 60+ MPG and CAN hit a 12.99 but the two goals do not help each other out, I also have 75 pounds of dynomatt and 100 pounds of soundsystem...... It I can average 45-50 MPG, drive 70-80mpg and base the whole way it will make a great commuter. I drive 45 miles a day on the freeway and very little stop and go.... keep in mind i will be running as lean as possible and datalogging every trip etc..... like a science project..... and if I blow an engine they are the cheapest part!

I am shopping clutches right now, I have a GT2554r (smallest garrett BB) and I'm guessing 180 max to the wheels for a while and wondering If I can get away with a Stage 1 Exedy or similar clutch .... any opinions? I may build a motor later and go with the good stuff but as of now I'm at double the original budget in time and money.

I'm the wrong person to ask. I called Clutch Masters as they come highly recommended from other platforms and asked them what I should order. They quoted me a good price on an FX350 kit on the phone for a lightweight billet flywheel and oversized clutch and I said "ship it."

I love the idea of their complete kit being a larger overall diameter. We currently have an Exedy OEM clutch in the car and it's so tiny! I didn't know there were clutches this small, but I come from the domestic world.

Oh, and nice choice on the 2554R. Great turbo for your goals.

I have the same one here as it's part of the Top Fuel kit I ordered, but I don't think it's going on the car. Our Fit is just a toy, so I'm thinking larger. Looking at the GTX2860R, but we'll see if I go full stupid.