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changing final drive ratio
oval TOFU - October 31st, 2005 at 02:25 PM

I've currently got a 1500 grearbox with (i'm presumiing) a 4.125 final drive ratio. With the on set of smaller diameter rear tyres, i'd like to keep my top speed and efficiancy intact.

How much work is it to replace the final drive? Can it be done at home or does it need lots of "VW tool number ####" to get it done properly?

Cheers

VWCOOL - October 31st, 2005 at 05:11 PM

It needs all the special tools

oval TOFU - October 31st, 2005 at 05:13 PM

dam.

How much do ya rekon a garage would charge to do it if they supply the R&P? (ballpark figure of course)

[ Edited on 31-10-05 by oval TOFU ]

Flintstones - November 1st, 2005 at 09:23 PM

Be cheaper and easier to change your tyres first, considering these are the final "gears" that determine the outcome of speed etc.

What size tyres do you have on it now?
What final drive did you want to go to anyway?
What were you hoping to gain from changing the final drive?

Cheers

VWCOOL - November 1st, 2005 at 09:45 PM

Quote:
Originally posted by oval TOFU
dam.

How much do ya rekon a garage would charge to do it if they supply the R&P? (ballpark figure of course)

[ Edited on 31-10-05 by oval TOFU ]


Four figures... if you can find a 'garage' that could do it

oval TOFU - November 1st, 2005 at 11:46 PM

Quote:
Originally posted by Flintstones
Be cheaper and easier to change your tyres first, considering these are the final "gears" that determine the outcome of speed etc.

What size tyres do you have on it now?
What final drive did you want to go to anyway?
What were you hoping to gain from changing the final drive?

Cheers


I want to go lower profile rears but keep the enging ticking over at roughly the same rpm as stock...so to counter act the smaller rolling diameter or lower profile tyres, i'd have to decrease the final drive ratio (taller).

225/60/15's - same rolling diameter as stock.
3.88
lower revs at highway speeds ie: better fuel ecconomy.

The place where I had my gearbox recoed said it was next to impossible (or not economically viable as they had to be custom made or shipped from the US) to install a taller final drive.. I don't see the difficulty in finding a 1600 gearbox and taking a servicable R&P from that..?

Flintstones - November 4th, 2005 at 09:11 PM

you've got some big boots under the car already!! 225's, that would fill the guards nicely:thumb
I gather you've got a swing axle, thus the ratio change request...get another quote/opinion, maybe have a chat to Wayne Penrose as he build's boxes as shown in his oval build up.

http://forums.aussieveedubbers.com/viewthread.php?tid=36521&page=3#pid335130 

Cheers

Mr Bubble Head - November 5th, 2005 at 09:40 PM

Chris

I'll have a dig for the number of the guy who built my box I started with a 1500 box and put shorter axels in I also played around with the final drive ratio I changed it for a kombi 0.60 from memory this will give me slightly lower revs in fourth gear ie taller top end for the freeways.

Hes been building gearboxes for VW's for 30 odd years so knows his shit plus has all the tools.

I'll find his number for you in the week by the way hes good on the pocket

nIck

oval TOFU - November 6th, 2005 at 11:42 AM

Thanks for the leads guys.

If you can have a dig Nick, that would be great. I'm going to contact my original builder to see what he says again and to address some shifting and oil leaking issues and we'll see what happens..

Cheers

oval TOFU - November 6th, 2005 at 11:44 AM

Quote:
Originally posted by Flintstones
you've got some big boots under the car already!! 225's, that would fill the guards nicely:thumb

Cheers


Yeh, they do fill the guards nicely! But they'll lprobably rub when I drop it a couple inches.. so hence the switch to thinner and lower profile tyres to match the front... ;)