final drive

[Rob_S]

f20 has fixed pinion yeah? need to remove gears etc etc to swap them.
small blocks has removable pinions making life easier, f10 has a 4.18 fd available, are big and small cwps interchangeable?

saw a custom cwp 4.66 on that barbados rally thread and i want that ideally, more info would be just super lol could get a few made up if i can find a good gear man

[jonlint]

4.66:1 final drive

I tried like hell to find a 4.18:1 final drive for the F20, but to no avail. I got my 4.66 final drive custom made by a guy in Finland:

http://www.rallysystems.com/

There is a guy in Italy that can also supply it.

http://www.colotti.com/inglese/

They are not cheap!

[Rob_S]

lovely
will see what i can do with the people i know
know how many teeth are on each wheel mate?

[jonlint]

know how many teeth are on each wheel mate?

I paid 920 euros for my final drive. I think it was 70/15 teeth. The guy at Rallysystems called Timo Kittela will help you. Try the cell phone number listed on the web site if you dont get an answer on the normal number. It was well worth it though - running on 15"s with even a 3.7 diff makes the gears too long. And if you modify the engine and can pull 7,000-7,500 RPM, the gears get effectively longer.

Hope this helps, mate

[Rob_S]

yup, i stay around 8k usually
may well have a chat with a boxbod i know of and get a few made up. cheers for the info mate, great stuff any more specs/tech drawings (lol) you have send them this way

[jonlint]

Not much technical to add. The pinion on the F20 is integral with the layshaft. The final drive came with the pinion on the end of the layshaft, and he sent a new bearing. I had to remove the gears off my shaft and put them on the new one with the 4.66 pinion. Then the crown wheel came with it, which i bolted my differential onto.

Dont have any photos, I am afraid.

[Rob_S]

good gen, cheers
how do you find it then, worth the effort i take it!

[kickastra]

Final drive

It was definitely worth the effort. We often had situations where one gear was too tall and the next gear short for a given corner exit.The 4.66 feels good everywhere, and gstill allows good top end for the longer straights - around 128mph on 15" tyres.

[Xedrah]

I'm also looking for another gearbox with a higher final drive or an other way to change the final drive. I'm afraid a F16 isn't strong enough for my tb'ed 20XE, and certainly not for the 2.2 engine that I'm building.

There must be a cheaper way the change the final drive, won't it?? I heard of a F16 diesel box with a 4.18 final drive. That would be perfect to install in my F20, but haven't found it yet.

[kickastra]

You need to be looking for a Combo or Astramax with the 16D engine.
F16 box with 4.19 final drive.

[Xedrah]

Thank you. It's a 4-speed probably, is it?

[Xedrah]

BTW, is it possible to swap some internals from that F16 to an F20? To keep it a 5-speed of course.

[kickastra]

It comes in both 4 speed and 5 speed.

[kickastra]

BTW, is it possible to swap some internals from that F16 to an F20? To keep it a 5-speed of course.

I speak under correction here, but i believe the layshafts are different sizes in the two boxes- the F20 is larger and can handle higher torque loads. Also, the number of teeth for the 3rd 4th and 5th gears differ from F16 and F20, so I imagine there are some differences. Both boxes come with wide ratios and close ratios. The 4.19 is from a wide ratio box.

HTH

[Xedrah]

Great, that's the info I needed. I can start my search now.