Hi everyone.

Been thinking about a new gearbox combo, and advice from BiX was to put up a post with my current thoughts and hopefully get some feedback from people. I've had a pretty thorough read of fullnoise's post about his prep for Dutton with dangerous's comments about ratio selection and so on - some awesome info in there so there's obviously some real expert knowledge around here !!!

Anyway - Jezebel is a road reg 70 IRS Bug whose primary use is hillclimbs (Mt Cotton) plus the other odd tarmac event (eg Qld Challenge).
- engine is a Pobjoy steroids, 7000rpm gives 100'ish at the wheels maybe a bit more. (still fairly new so not going that high yet)
- currently has a standard L bug box (3.875 r&p)
- tyres are 632mm OD

At Mt Cotton feel I want a bit taller 1st and then shorter on 2nd and 3rd. Don't get 4th at all there, but highway revs still need to be sensible.

My thinking so far:
- Rhino case with HD side plates
- 3.875 r&p
- Quaife ATB diff
- Albins internals, with ratios of 3.44/2.23/1.48/1.00

Questions I have:
- are there any ratio combinations known to give probs, or that should just stay away from
- ZF vs Quaife pros and cons (I really like the concept of a Quaife, but don't want to start my own horror story)
- getting a Rhino case - any places around that sell them, or is it a case of importing myself
- anyone know/recommend a good gearbox builder round Brisbane or maybe Gold Coast.

Keen to hear whatever ppl have to say - I'm out to learn as much as I can with the whole hillclimbing caper. For me its more about having fun than being super-competitive.

Thanks !!!

Hello Sides(sorry i dont know your real name),
I would stick with your SSC tranny case,
and run the latest model VW side cover or aftermarket one if you like.
If you want you can go for the Rhino but I dont think it is any stronger than the case you have.
I think that Mick Motors has the Rhino in stock.

Albins only stocks a few ratios for first and second, unless you want to spend more fore a custom order.
He has a 3.55/ 2.25 combo, or a 3.33/2.077 combo.
Those 3rds and 4ths should be OK, being that it is more for fun than trying to push that last little bit.
Just make sure the part numbers fit each other.
ie the 3rd and 4th are 002 style to suit the Albins mainshaft set.

The gear ratios are a good spread,
but the rev-drop between them may be worse than stock,
particularly into 4th gear.(3rd is better)
This is a bit of a comprimise, but it does depend on your favourite ratio at the track.

If you choose an off-the-shelf mainshaft set for 1&2, then you may need to change your plan slightly.
If you go for the 3.55/2.25, then a 3rd between 1.444 and 1.5 will be fine.(as you have chosen)
If you end up with the 3.333/2.077 then a 1.4 to 1.444 may suit better.

Of course if you go for a lower 4th gear, you can lower 3rd some more.
It just depends on how each particular gear suits your most common track and whatt is bearable on the street.
You would hate to run out of steam in a particular gear if it is the wrong choice and have to change up at an inconvenient point.
LIkewise if it is to tall it wont accellerate fast enough.

I have fitted a couple of the Quaiffe diffs for friends, and the quality was excellent.
These ones had bigger splines so that bus CVs can be used, and also eliminate that weak point.

go for the Quaife over the ZF.

Gday sides

Is that your car in the latest VW mag? lookes cool.
I run a 1976 single side plate beetle box with standard 1st standard 2nd then 1.58 third and 1.21 4th gear ratios.The ring and pinion is 4.375 which would be a little low for street use im sure.Ifind 1st and 2nd a little short but with such a close 3rd she pulls quickly out of tho hole,andstays in the power band.

As far as diffs are concerned, my biggest leap forward in lowering my times at tracks was the purchase of a LSD.You dont realise how much time you lose especially when turning left and of the start line.

My LSD is a ZF purchased from the samba VW site.If you do nothing else with your gearbox sus out a LSD.


Cheers Col

OK, cool - sounds like I'm sort of on the right track.

Dangerous - thanks for the tip about the Rhino case - seems a pretty exxy option, especially if I don't need it !!!

Checked with Albins on what ratios they keep stock of, and although they stock the 3.55/2.25 and 3.33/2.07 sets they're out of anything between 1.40 and 1.50. Good bit of news tho is they can make whatever I want with about a 6-8 week lag (cost stays same) and luckily time isn't an issue for me !!!

I'd seen that Quaife do an IRS beetle diff with bus splines - I like that idea, but what's a good setup from CV's outwards then ? I'm assuming that bus CV's won't fit up to bug drive shafts (I don't know much about buses)

So my plans are getting just that little bit clearer - good stuff.



btw Col - haven't seen the latest mag, so not sure. It's possible since Craig was out at Mt Cotton recently taking a few pics, but if it's a dark blue with 70 on the sides it's bound to be me !!! Getting some form of LSD was the starting point since I'm now spinning the inside rear quite a bit - the rest of the box changes have just snowballed from there...

If you are in no hurry, I may be able to assemble it for you (since trannys are my hobby).
But in Brisbane, guys like Leon's, German Auto, and Phoenix Engineering do tranny work also.
There may be others.

The Bug axles are fine, and the bus CV can be counterbored slightly to fit the type1 axle.
You can use 'Thing' or 924 stubs on the outboard end,
or weld on some locating rings (made from bus flanges) to the type 1 stub and you are away!

[ Edited on 14-8-2007 by dangerous ]

Thanks for the offer Dangerous - I'll bear that in mind. I'm assuming you're going to Warwick - hopefully will get a chance to talk some then.

Also that's good info on the bus CV's - seems some more researching for me to do !!!

has anyone seen these before?

http://www.phantomgrip.com/how_it_works.htm 

Thats a very old rally trick that allot of guys have used. Normally home made for under $50. But i wonder, as iam pretty sure it acts like a locked diff and then allows slip, rather than being open and locking as slip occurs.

bix, are you using an LSD?

Not at present, looking at getting a deal with sides when the tax man gives me some money.

Rallydave from here ones a home made version of the LSD you pointed out in his rally car.

[ Edited on 28-8-2007 by BiX ]

[ Edited on 28-8-2007 by BiX ]

yep, I've talked to him and I'm seriously considering making one up.

Rallydave had some cool pics of his bug throwing major rooster tails at a grass motorkhana... had to look at the photo a couple of times before you realize the dirt was coming from the LOADED wheel while the other side was a couple inches in the air....so his setup definitely works.

Would be perfect for a Rally/dirt/Offroad car...

yep, it's definitely getting the thumbs up! I do it straight away!
...once I mow the lawn, put the kick boards and picture tails on, patch and paint the broken fibreglass, paint the new coffee tables and fix the kitchen door...

but thats daytime what about the night time!!

off to mow the lawn again...