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what axles and CV's for +250HP ?
72RSbug - August 4th, 2007 at 04:48 AM

I've got a type 1 Pro street IRS transmission on my EJ20TT (280HP) and stock type 1 trailing arms but these will not last very long I suspect.

Was thinking of using 944 turbo axles but am not sure if the dimensions will work and also have no idea on what CV's to use.

What are you guys running?

1303Steve - August 4th, 2007 at 07:56 AM

Hi

The trailing arms wont give you any trouble. Good stock CVs are OK up to a point, the next step is Kombi CVs, then Porsche 930 CVs. With the stock CVs and the Kombi CVs you can use stock axles, which will be fine. With both the Kombi CVs and 930 CVs you will need special flanges on the stub axle and trans output. With the 930 CVs you will also need special axles.

Between breaking stock CVs and the need for Kombi Cvs you will most likely have a transmission failure. Stock CVs can act as a fuse, or weakest link, just carry a spare complete axle in your boot.

I ran Kombi CVs in my old car, they survived my stupid driving which broke a Quaife diff output shaft, I'm going to run 930 Cvs in my new car because I have an extra strong trans and I need the extra operation angle that they give.

Steve

reub - August 4th, 2007 at 10:35 AM

930cvs, modified drive flanges, romac billet axles...:thumb

555bug - August 4th, 2007 at 06:45 PM

CB stub axles (type 2 flange) and cb type 2 drive shafts with high tensile bolts, this should be good for the sort of HP you are expecting. If you are running big angles opt fro the 930 cv's.

Cheers Stephen

seagull - August 5th, 2007 at 02:19 AM

If you have a key way main shaft you need another very soon :)

pete wood - August 7th, 2007 at 12:07 PM

If your axles are nearly straight, you may well be able to use the stock beetle CVs. Angle kills them, just like Steve said. Kombi CVs are a lot stronger than you may think too. A number of turbo Sports sedans have used them and they are putting out a lot more than 250hp. Kimm Garland's (Indian automotive) blown V6 twincab uses stock bus CVs and he told me he's had the same set for 10 years. He regreases them and swaps them around each year and they just keep going strong. He's blown a couple of gearboxes up and chewout a 091 ring gear, but the CVs are still good. And that's behind 300hp+ and heaps and heaps of torque. Just make sure you get the German Lobro CVs.

72RSbug - August 8th, 2007 at 12:19 AM

some very helpfull info here guys, thanks.

@ pete wood, bus CV's are larger in diameter then type 1 CV's, correct? Maybe I could use bus axle stubs on the wheel side but what about the transmission side then?

pete wood - August 8th, 2007 at 08:23 AM

yes bus CVs are larger diameter. bajawes had a solution to this on his website...

http://www.offroadvw.net/bajawes/wes/aug_sep.html 

he even has some drawings to use...

http://www.offroadvw.net/tech/drawings/drawing.htm 

This is the cheap way of doing it and has worked really well for Wes.

I have bug stubs that were machined and then had bus CV flanges welded to them, not too pricey but if I'd seen Wes' setup first I'd probably have done that. They were made up by a VW specialist in Aust. Any machine shop could do it for you. There are a number of US companies that make bus to bug output flanges and stub axles. Although stub axles are certainly more plentiful than the output flanges due to the offraod industry. Just look around. Wes' bits have held together well with his setup, but keep in mind he's using a 200hp NA motor and torque is the problem for driveline parts. So a turbo motor putting out lots and lots of torque might be another proposition all together. But then, Boof's EJ20T car is still using all beetle CVs and shafts and he's had no CV breakages. As I said above, the key is keeping the axles and CVs as straight as possible, in which case they are nearly bulletproof.

matberry - August 8th, 2007 at 10:14 AM

Angles are bad for cv life but tyre size is also abig killer!
No wonder offroaders have the most drama with joints!

Matt

supa74 - August 9th, 2007 at 12:04 PM

if somebody is using a 091 bus tranny, why not just use the bus cv's all the way to the brakes, n mount bus wheels on the rear of the buggy??? just pondering on this thought. if somebody isn't picky about having different wheels on back n the bug wheels on front. wondering if it can be done

MickH - August 9th, 2007 at 01:53 PM

Quote:
Originally posted by supa74
if somebody is using a 091 bus tranny, why not just use the bus cv's all the way to the brakes, n mount bus wheels on the rear of the buggy??? just pondering on this thought. if somebody isn't picky about having different wheels on back n the bug wheels on front. wondering if it can be done


The bus axels are to long to use on the bug rear end and the bus hub is different again..it doesn't physically fit and is a larger diameter axel so reuires different brakes etc etc....the way Wes has done it by modifying the CV pattern on the flange is the easiest way and it allows you to use modified beetle axels with the bus CV's,otherwise use porsche rear stubs with the modified beetle axels and bus CV's,as I've done but that costs $$$.....

[ Edited on 9-8-07 by MickH ]

Flintstones - August 9th, 2007 at 10:43 PM

Or you can get VW Thing stub axles and gearbox output flanges with either Thing or Kombi cv's on beetle axles.

That'd be the easier option and cause it's all OEM you can be assured of the VW quality.

Of course you'd need to source the Thing parts from the USA...

Cheers

MickH - August 9th, 2007 at 11:18 PM

The "Porsche" stub axels are actually branded VW/Audi..