now this aint a major problem at the moment, but it soon will be after stoneleigh and plenty of motorway miles.........I have been out crusing in the fug, on motorways 70mph is achieved with 4000rpm......now thats a tad too high!.........it should be around 3000rpm - ish.........

reading the BBT catalogue, they do a street bullet gearbox with a 3.88 ring and pinion set, they say that normally at 97mph = 5000rpm, but with a 3.88 ring and pinion, it will be 4000 rpm, so this is just about what I'm looking for, a 1000rpm reduction in 4th gear........for £600 - ouch........although the cost may be a good investment over a 40 year old knackered 10th-hand box!

now I think this has been discussed before - which swing-axle gearbox do I need that will already contain a 3.88 ring and pinion?.........what is the box number/code?..........I seem to remember its a 1500?.........

what should I be looking to pay for a GOOD secondhand item?.......does anyone know of one available?

this is a winter project I have planned, then I will also upgrade the 95bhp 1.5 alfa-sud motor to a 118bhp 1.7 alfa clover-leaf jobbbie.........

Please check as VW's really ain't my strong point,but I was under the impression many of the later ones,73 to 77 were that ratio. Is the gear box past replacing the ring and pinion with the ratios you need,they must be available if a model had them as standard. Don't know specifically for beetle,but ring and pinion kits can be made to spec cheaper than you'd imagine.

Hi Knighty,

Give me a shout when you find out the gearbox code, I've got what might be a 1500 gearbox (I believe I was told it was) in the garage.

I'll try and remember to have a look at it and get the code off it later.

Edit : There's a list here, some of the 1500's and 1600's have the ratio you're after : VW Beetle Gearbox Codes and Ratios

Cheers

Paul.

hey paul - yes I would be very interested to know the code from your box!......I'm assuming its swing axle?.......do you have any history of it?......whats the general condition?

where abouts on a gearbox is this code located?.......then I can actually identify what I already have!

The only swing axle gearbox with 3.88 was the 1600 GT, whereas a 1500 box will give you 4.125 and a 1300cc is 4.375.

Double jointed gearboxs as fitted to the 1302 and 1303 (1300cc) is 4.375 whereas the 1302S and 1303S (1600cc) are 3.88 final drive.

Apart from rotating the wheel and counting the revs the only other way is that for the 1600cc box's (including the 1500) the bell housing is machined out further to accept a 200mm clutch.

The GT box is rare (only 1500 imported in '73)


Hope this helps :)

Borrowed from another site :

Will have a peek at some of mine in a bit and see what I can find.

Ok here goes.....

The yellow box is where I think the codes are supposed to be. On both of my other gearboxes (an old AH coded box with knackered synchro and the AT I plan to use instead) this is where the code resides.

However on the one I thought was the 1500 box there isn't an alpha code there!

Just 9803843

As to swingarm etc...

I never have a clue about this stuff, not a Beetle bod.

But the joint onto the gearbox is shown below -- Tigger ???

As to the condition:

I came back from holiday to find a very stripped Beetle on my drive a few years back.

When I persuaded my mate to remove just the bits I might need he did so in a fairly brutal manner involving oxyacetylene and cutting through the shafts!

I then realised it wasn't going to fit to my driveshafts and it's been sitting there since.

Probably ideal for ripping bits out of, but I guess we're still not sure of the ratios.

excellent replies paul & Tiggar......thanks for the effort with pics paul........sounds like my chances of finding a 3.88 are slim and none.

Tiggar - how hard is it to replace the ring and pinion in a swing axle box with 3.88 items?........does it require specialist equipment.......or do you think I could do it?........where could I get the parts?.........G & S or BBT perhaps?

If you have both gearbox's there in front of you it is a striaght swap like for like. But it depends on the suspension type you are using? Knighty, have you trailing arms or a swing axle??

Paul, the box you show is a early swing axle.

Knighty

whats all the fuss just change the pinion ring on your gearbox BBT sell them .
It's not that hard to do.

Just done it on a friends 1600 gearbox not too much grief

I have a 1500 in one of my fugs so will post the code tommorow if get time.

Tiggar - mines deffo swing axle, I will read off the codes to identify the internals for sure.

Caloun - how much for the 3.88 ring gear from BBT?.......sounds the way to go......it would save grief too, as my box is fitted with a special input shaft for the alfa adaptor conversion........does the box need removing, or can it be done in situ?.......from what you say I assume all the pinion gears are the same???...

whats all this "in one of my fugs"........do you have a fleet of them now then :blink:

You have to take the gear cluster out of the 3.88 box, take the 3.88 ring off the diff and then swap it with the bits in 'your' box...so yes it has to come out and its a complete strip down. You also need to 'pre load' the ring and pin once re-fitted.

Looking at your website ...you'll have no problem !! B)

Otherwise convert to trailing arms (mucho better) and find a 1600cc box form a 1303S or 1302S Beetle :P

yes more than one that is all I am owning up to. ;)

looking for an f30 next :P

re price I seem to remember about £100.00

ssp link

http://www.vwheritage.com/ssp/Gearbox-Comp...?templateID=ssp

no prob for a man of your talent :)

much easier than indexing the rear suspension which you have done

Phoned BBT yesterday, they no longer sell 3.88 rings, suggested I buy one of their boxes - sod off!.......or I now see cal has come up trumps with the SSP link - nice one cal ;) .......or they suggested I phone cog-box, which is my next avenue.......yes I could probably do it, but since fatherhood has arrived, its all a question of time, I dont have any!.........

I'd rather Peter from cog-box do the work, and also give it the "once over" to diagnose a full bill of health - hes a legend in vw drag racing circles......if BBT's boxes are as bad as their engines, theres no way on this planet I'm handing them £600.......I'd rather pay cog-box for peace of mind!

I will never convert to IRS - it adds 20Kg, and its unnecessary for an on-road fug, the handling debate doesnt apply to a fug.......to a beetle yes......to a fug with a literally non existent centre of gravity........no

Ahh-h something else we can have a chat about next weekend then... :D

Knighty
Seems a lot of money to me,but is ebay item 300106761882 what you're looking for?

I've collected a fair bit of information on VW Type 1 transaxles at:

http://www.shining-wit.net/rick/buggy/design/transmission

There's also a useful calculator to give road speeds at each RPM for different wheel sizes and gearbox ratios.

A simple way of changing the engine RPM for a given speed is to change the diameter of the rear wheel/tyre combination - bigger diameter = lower revs. Much easier than ripping gearboxes appart :) IMHO of course...

Right, I have just phoned cog-box, and I thought he was a bit more local, turns out hes the other side of London in middlesex, and hes a tad busy at the moment, so I might tackle it myself.

Caloun - when you said change the ring, surely you meant the pinion too?........this is the bit I'm more concerned about!

its changing the pinion that looks the hardest bit, and setting the pre-load, how is that done?.....also, will I need any workshop grade tools?......like a bench press, or can it all be done in my garage:-

http://www.cbperformance.com/catalog.asp?ProductID=1425

I wont have a donor gearbox, just the parts I buy, so will I need anything else, like shims special tools?

I have just asked a mate at work, he took at the pic in the attached link and he thinks I will need access to a hydraulic press, in order to remove and install the bearings and gears on the pinion......do you agree?

he has don a lot of truck gearboxes, so he thinks the principle is the same......he thinks the best way to do it is set the pre-load on the diff, then play with the pinion distance in order to get the correct wear pattern between the ring & pinion teeth, using something like engineers blue in order to get the mesh pattern correct.......am starting to think I can actually do it