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gearboxs for larger motors
phoenix_dr - January 8th, 2011 at 11:55 PM

[size=4]something that has been bothering me lately as I work on the body of my dak dak is:

what motor/gearbox should I put in it?

it's a 65 beetle (stock as a rock)
So with a larger motor the standard gearbox ratios wouldn't be great, not to mention strong enough to handle the extra revs, so I was wondering what other people have done to their early beetles to fix this problem.

Would a later IRS pan be the best option?
Maybe a Tpye 3 or kombi box? (IF... I can find one)
How much fabrication is required for these?

Are there other options? like stronger, longer gears?

Any advice/ thoughts/ previous experience would be really helpful.[/size]

barls - January 8th, 2011 at 11:57 PM

im using my stock 1302 box but have been thinking of dropping the diff ratio down to 3.88 or 3.44 just havent had the money to get it done yet.
ideally the 1303 box with the signal side plate is the go as its the strongest of all the boxes unmodified

phoenix_dr - January 9th, 2011 at 12:03 AM

wasn't the 1302 a 70's model gearbox? do they fit into the early beetles?

barls - January 9th, 2011 at 12:07 AM

i think they are a little different but not 100% sure. its the 1600 irs gearbox with the 4.125 diff.
im sure you could fit one if you really wanted to. hell ive seen the porsche 915 box in a bug

phoenix_dr - January 9th, 2011 at 12:07 AM

How much difference do you think that will make?

what motor are you running with that gearbox?

barls - January 9th, 2011 at 12:11 AM

stock 2L t4 with a mild cam, 40mm dels and custom exhaust.
i know when i changed rims and tires to slightly bigger it dropped my cruising rpm by 1000 so now im just below peak at 110kmh.
i want to change the diff to drop it down to about 3grand.

phoenix_dr - January 9th, 2011 at 12:25 AM

thats what I'm thinking...

anything around 2L(with a stock gearbox) is a great option for driving around at 60km's, but get on a freeway and it will be up in the higher revs with the stock ratios.

who would you go to for new ratios? America?

What size wheels did you go to?
16'
17'

barls - January 9th, 2011 at 12:31 AM

ive got 16s with slightly bigger tires on the rear.
if you want some good advice on boxes try pmin dangerous on here.

phoenix_dr - January 9th, 2011 at 12:36 AM

Cheers Barls, Thanks for the input :tu::tu:

Joel - January 9th, 2011 at 08:45 AM

It's a big job to convert to IRS.
It;s a body off and bit of chassis surgery but worth it if you want a car that handles better.

If you dont want to do the whole body off thing and stay swingaxle I;d just chuck a 1500 beetle box in

That will give you a pretty strong box for a mild 2L and the ratios are the same as the twin side plate superbug boxes.
Theres no huge advantage with a 3.88r&p over a 4.125, theres still pulling similar revs in 4th

My rotary bug had a DC type3 box in it, the only difference was it had a longer 3rd.

you dont wanna slow revs in 4th too much or you'll start getting overheating probs