What transaxle

I am new to this fourm- and seek advice on which gearbox to use..

I am racing with a GTD40 in the swedish Modsport series- For the coming season I have upgraded with a bigger engine than previously. My previous engine was a 347 with approx 500hp and 600Nm, last race of the 2012 season I killed my reinforced UN1 box.....The engine for the 2013 season will be a 427 with 700hp and approx 850Nm(If I remember correct from the dynopapers...)

Anyone have any suggestions for a suitable box for my application that will last under racing conditions ?

Looking forward for comments....

Brgds !
Andre
 
A lot depends on your budget.

ZF/ZFQ/Porsche G50 I would guess if cost isn't an issue. If it is, a strengthened Audi 01E might live up on the track as you aren't going to be launching it.
 
Simple....6 speed UN1, dog synchro, straight cut gear box with LSD.

No major gear linkage mods.

No clutch system mods.

No bell housing change.

No starter motor change.

No engine mount mods.

No aft transaxle mount mods.

No exhaust sys mods.

No half shaft change.

I'll probably think of a few more too!
 
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Simple....6 speed UN1, dog synchro, straight cut gear box with LSD.

No major gear linkage mods.

No clutch system mods.

No bell housing change.

No starter motor change.

No engine mount mods.

No aft transaxle mount mods.

No exhaust sys mods.

No half shaft change.

I'll probably think of a few more too!

Your comments are highly appreciated, however I do not think any UN1 will last my new engine....A couple of years back, when I purchased my current box, I considered to go for the 6 speed seq alternative as well. After discussions with the company that provided me the box- their recoomendation was an uprated 5speed box with Quaife internals + ATB. They also provide the 6 speed seq box, it was however not considered as strong as the 5 speed one I finally bought.....

It appears to me at the current stage that the Prosche box will be the preferred alternative. I went to Autosport2013 in Brimingham last weekend and got some new input to gearboxes as well

I spoke to representatives from Quaife regarding the ZFQ, however they were reluctant to suggest this box for my applaication to the torque limit of this box, which seemed to be in the upper 500nm range...

There were a few other that may be evaluated as well, which were:

- Graziano(several versions, and fitted in Audi R8, Ferrari, Lambo etc as OEM)
- Albin
- Hewlands(a bit expensive, but....)

Any suggestions will be appreciated....

Brgds !
Andre
 

Mike Pass

Supporter
Big Hewland if you are racing. Anything with helical gears will screw them out of the casing with that much torque. Good enough for the monster motors in Mclaren M8s etc.

Cheers
Mike
 

flatchat(Chris)

Supporter
Big noise power plants NEED big noise transmissions -- don't be a tight ass here
--- The Ricardo (Ford GT) is probably a good option for strength and budget
 
Hi Andre,

I have a Hewland VGC that was fitted to my RF117 it has plenty of capacity for the power figures you are talking about. We also have the CNC milling program for a billet bellhouse to suit a Windsor block. It is strong enough to enable you to hang suspension components if required (we are not allowed in our category) If you are interested I will send some pictures

Regards

Iain
 
The Hewland VGC is a gearbox that is no longer made. Parts for now are still available, but I would not expect that to last for too much longer either.

Just FYI.

Erik
 

Andy Sheldon

Tornado Sports Cars
GT40s Sponsor
Andre

Trying to reduce the weight of the car would be a good idea. The GTDs are very heavy.

Darrin

A UN1 on a Coyote in our chassis is a very light car. The box would not break.

Andy
 
Other than a Hewland or a Ricardo, your choices are limited in that hp/tq range. Very limited. Even the 930 4speed box is not rated for anywhere near that much hp/tq. I've seen a 930 box on the bench and the gears are dramatically larger/heavier than other porsche/audi boxes, for example, but for that kind of hp/tq and race conditions you need a Hewland or Ricardo. Hewlands are race proven, the Ricardo not so much, but likely both are your best bet. The Ricardo does not have straight cut gears so it's a much quieter and civilized box by the way.

Good luck and please post your findings.
 
Cliff,

You are spot on with the Ricardo being a bit more civilised that the Hewland, I have nick named my VGC Mike (After Mike Tyson) you have to really agressive with the gear changes, in fact the more agressive the easier the change. Noise has not been an issue, i simply cant hear it over the engine !

I spent some time talking to Ricardo before opting for the VGC and they were quite willing to do the required engineering to change their TX to a straight cut dog box but needed a minimum order of 50 !

Iain
 
Thank you for all comments and suggestons- they are all highly appreciated as this is an aera of concern for the coming season....

There was a comment related to the weight of the car- The car is about 1040kgs, which is somehow lighter than original, however it would of course be benficial to have this further reduced. Some of the cars I compete against are down 600kgs.....

Another comments was related to a Hewland VGC box- Hewlands have "always" been high up on any racers wishlist- when it comes to cost levels of this type of box, do you have eny indications of the range ? I am also a little concernced related to parts availability for these boxes in my part of the world......

It appears to me that maybe the way to go will be a Porsche box, as parts are plentiful and easily available almost anywhere. They also seems to be able to handle the torque...Any comments related to this will be highly appreciated as well.....

A fellow racer have a BMW M1 with a Dodge R5P5 Nascar engine fitted, which drives through a Porsche box- it seems to last this engine, however I believe the torque of this engine is lower than mine, even if the power is around 840hp.
 
The requirement that is the toughest to meet is the 850 Nm. The only transaxle that I know of at the moment that can handle that is the Hewland LWS, rated at up to 950 Nm depending on final drive ratio.

You could probably get away with a heavily modified G50, G50/50, G50/52, or some of the G96/G97/GT3 series boxes. The Audi 01E can also be built up pretty well, there are some nice billet side plates available, and it can take some G50 parts as well.

Just my opinion based upon research I have done.

Ian
 
If you have the space available you might want to consider the G96.50, G96.88, G96.96 or G97 versions as these have been quite good with high HP and Torque applications. They are a bit pricey but I have a feeling that you are going to run into this regardless of your choice due to the Torque requirements that you have on this.

If you do decide to try one of the G50 variants, I would recommend the G50.52 as this is by far the strongest of the G50 options.

I hope that this helps a bit.

Erik Johnson
 
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