Custom 5th gear ratios?
 

I'd like to know if eco-modder members are interested in custom 5th gear ratios and for which vehicle?
There is a possibility that custom gears could be machined if we can get enough interest in a particular transmission and get a group buy kinda thing going.

My first vote would be for honda D-series transmissions, should work for 1992-2000 years and maybe 1988-91 depending on which trans. Maybe shoot for ratio's in the high .5XX's?

I know there's gotta be some Miata and Protege5/Mazda 3 owners out there that would be game, which may also cross over to Ford products as well.....

I'm sure this place could make them:
http://www.cgearinc.com/capabilities.asp

I'd be interested in a super tall 5th :)

Now you're talking! Gearing is a powerful tool for improving MPG.

Can you do a 0.55:1 top gear for my ZF-6-650?

This would be something we want to have machined in batches, otherwise it will be way too expensive to run one off's. I'm expecting the honda to be a go because there are so many but we'll have to see for the ZF-6. I'm assuming your refering to the 6sp manual in the F350 super duties?

Based off of a DX or LX Civic trans with a 4.08FD, changing to a .600 5th gear would yield 69mph at 2500 RPM based on a 22.8" tire diameter. Many of the 2-valve and VTEC-E engines make good torque at 3000rpm and should be able to pull this gear on the flats.

Perhaps if people poke around on their separate car/truck forums to get other people in we could get enough for orders of various things.

PS: I'd be putting it in an 89-91 D series. I was thinking probably my HF but if I can get a tranny with closer gearing on the first four I might put this in for the fifth. I feel like a bit more pep on the low end for getting up to speed quickly might help mileage a little.

Novel, but I imagine the fuel payback is pretty long-term. My Protege5 gearing is VERY short. I accelerate without chugging in 5th gear at 40km/h... I'd rather be at the same rpm at 65km/h.

wow... if you could make some custom super high ratio 5ths for VW transmissions... higher than their already high diesel 5ths (common swaps among the VW community), I bet I could rake in a TON of interested people

I've e-mailed custom gear with my intents, we'll see what they say. I started my workforce life as a machinist/cnc programmer, and once they get the program perfected it's just a matter of loading the gear blanks and hitting the go button. The more that can be purchased at once the cheaper they will be. Obviously for those that can't work on their own trans the install price would make it a negligable investment, but for many of us it's just what we've been looking for.

I really need a taller 5th. Previous owner swapped out for a shorter one to get a faster 0-60. . . dunno why you'd want that with a Del Sol. . .

but I am not currently on the market for parts of any kind.

You may be confused... the previous owner may have put in a shorter final drive gear to reduce his 0-60. Any knob that shifts into 5th gear before 60 shouldn't be driving if his intention was to get to 60 quickly.