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Nice transaxles for small cars?
Alez - 27/5/08 at 09:44 AM

Hi All,

I'm having a first preliminary think about a spaceframe Mini project. I'd like a car mid engine and was thinking about the transmission. Most of these cars use a FWD set, the ZCars VTec for instance being very similar to the Atom and using the Honda Civic engine and gearbox. I don't like this because it makes the engine sit high and quite to the rear. I think the engine position this gives is poor compared to the chain driven ZCars R1 or similar cars. For car engine, I like it Retoga Zetec style:



These use a transaxle from Elite Racing Transmissions. I think Hewland has similar transaxles available as well.

I'd like to have any comments from you.
Any experience with these?
What engine(s) would I want to look at? (I'd like a proven solution I can use for reliable 200 bhp, I was thinking Honda Civic, Toyota 4A-GE, Zetec, Duratec as these are well known.)
Are these LSD diff?
What's a "H pattern dog box"? (I thought Hs were sincromesh and sequentials were dog but I've seen one or two described like "H dog" on the web. I like it quick and sequential as one would imagine.)
Any other makes?
How do I know which transaxle goes well with which engine in terms of adapting it and also in terms of torque? (I'm looking at a 700..750 kg car I'd think, with Mini dimensions, maybe 195 or so tyre width and so on.)
I know these will be expensive to very expensive, but any rough ideas of cost?

Cheers,

Alex


tegwin - 27/5/08 at 09:55 AM

Thats a pretty tidy setup...I like...


Have you considered the VAG transaxle as shown in the 1.8T passat, Audi A4 etc?

How about simply using the passat/a4 as the donor....you can tune the 1.8T engine to about 350hp if you have the inclination


Fatgadget - 27/5/08 at 10:14 AM

Nice.But £8,000

[Edited on 27/5/08 by Fatgadget]


Alez - 27/5/08 at 10:40 AM

quote:
Have you considered the VAG transaxle as shown in the 1.8T passat, Audi A4 etc?


Interesting..

Is it this one? Not sure the rear would fit in a Mini but looks good for similar enough projects?


quote:
Nice.But £8,000


Now that's a show stopper


Alez - 27/5/08 at 10:49 AM

What do Elises and Exiges use? Just the original gearbox that comes with the engine? i.e. Rover K, Toyota..


worX - 27/5/08 at 11:06 AM

You can get second-hand hewland gearboxes that may already have ford gearbox mounting adaptors from around £1500GBP but they will need rebuilding aswell...

Steve


Minicooper - 27/5/08 at 11:14 AM

I think it will be very tight for space, the seats would have to be well forward and I'm not sure you would get the overhang of the gearbox at the rear in either

I can do a few basic measurements if you want

Cheers
David


coozer - 27/5/08 at 11:16 AM

Beetle or VW camper??


Fatgadget - 27/5/08 at 11:24 AM

quote:
Originally posted by coozer
Beetle or VW camper??


Dont you have to turn those upside down with all the attendant problems or something?


tegwin - 27/5/08 at 11:50 AM

Dont think you have the right VAG tranny there...


The one I found at my local scrappy (£250) was pretty short....

But as has been said...perhaps too long for a mini!


Mr Whippy - 27/5/08 at 11:54 AM

quote:
Originally posted by Fatgadget
quote:
Originally posted by coozer
Beetle or VW camper??


Dont you have to turn those upside down with all the attendant problems or something?


as far as I can remember thats not the case as seen in formula v cars. Note the later cars 1303 etc have proper suspension as per the 911's with normal UG's on the driveshafts if your not keen on the funny swing axle idea.




[Edited on 27/5/08 by Mr Whippy]


finlay - 27/5/08 at 12:00 PM

quote:
Originally posted by worX
You can get second-hand hewland gearboxes that may already have ford gearbox mounting adaptors from around £1500GBP but they will need rebuilding aswell...

Steve


can you give any sites they would be on sale on ?

cheers


Alez - 27/5/08 at 12:22 PM

quote:
Originally posted by MinicooperI can do a few basic measurements if you want


Very kind of you David but for now it's just putting together a few thoughts so don't bother just yet. It's more this kind of discussion we are having what I was looking for just now

Cheers,

Alex


Mr Whippy - 27/5/08 at 01:06 PM

Saab 900, Renault and Audi also have used that layout. You might consider even using an automatic transmission as this will do away with the complex gear lever linkage and will effectively give you instant acceleration at the lights. You can also wire the modern electrically controlled ones up to paddle shifts.


Dusty - 27/5/08 at 03:33 PM

The beetle/transporter transaxles live with the engine behind the axle and the box in front. So yes you do have to invert if you want the engine in front of the axle. Same with the porsche ones. I'm sure I remember an article in PPC a few months ago which also looked at alfa trannys.


Volvorsport - 27/5/08 at 04:23 PM

std beetle boxes need strengthening above 150 hp , and for 15 inch wheels .


Ringius - 27/5/08 at 08:55 PM

Shows a quattro box, the 2WD box is much shorter, think away the black part of the transaxle and you get approx size. The 016 transaxle (as fitted in Audi 80/100/200 is approx 18" from centre of drive-shaft to back-end, the 01E (A4, A6, ...) is shorter still. If interested, I can upload a couple of drawings of the 016-box into my archive.

As for the beetle transaxle, IIRC - it is possibel to invert(?) the pinion gear and reverse the box without flipping the whole transaxle.


Fred W B - 28/5/08 at 06:23 AM

See 016 details in this thread

Tha older smaller Audi "80" used a smaller box that may be more suitable for you

cheers

Fred W B


drive train
drive train


[Edited on 28/5/08 by Fred W B]


Alez - 28/5/08 at 08:21 AM

quote:
Originally posted by Ringius
the 2WD box is much shorter, think away the black part of the transaxle and you get approx size. The 016 transaxle (as fitted in Audi 80/100/200 is approx 18" from centre of drive-shaft to back-end, the 01E (A4, A6, ...) is shorter still.


That'd be good news, but from the picture just below it doesn't seem so, that has a smaller black end but then it has another bit attached to the rear of that

Then again that box seems to take a lot more torque than I'm looking for, so maybe that 01E you mentioned is worth a look?

quote:
Originally posted by Fred W B
See 016 details in this thread

Tha older smaller Audi "80" used a smaller box that may be more suitable for you


Yes that 016 is definitely a monster I'll need to have a look at the alternatives you have been suggesting.

I've been looking at your thread and that's a very impressive job Well done!


Alez - 28/5/08 at 08:28 AM

I think this is the one mentioned:



Found here:
http://cgi.ebay.co.uk/Audi-A6-80-100-Cab-V6-Coupe-5-Speed-CDX-Gearbox_W0QQitemZ290154113215QQihZ019QQViewItem

[Edited on 28/5/08 by Alez]


MrFluffy - 28/5/08 at 02:11 PM

The vw transaxle pinion can be swapped easily to invert the drive direction, I have one here that has a hewland ford adapter plate on it, and it was immediately apparent as soon as the bellhousing was off..

My vote is for the Renault un1, http://www.un1.co.uk/
The ng9 is a bit shorter, but its weaker too, and the un5 renault master variant has a unchangeable and almost unusable low diff ratio.

Cue scruffy mockup shot :-


[Edited on 28/5/08 by MrFluffy]


Alan B - 28/5/08 at 02:20 PM

Anyone spot the "Z" bar on this....the opposite of an anti roll bar......allows roll but stiffens both wheels trying move together...

Irrelevant I know...





[Edited on 27/5/08 by Mr Whippy]



Alez - 28/5/08 at 03:23 PM

quote:
My vote is for the Renault un1, http://www.un1.co.uk/


Is that not massive for the application in terms of weight, size and torque rating? That box is used for V8 applications all the time I think.. Let's have a look at that NG9

[Edited on 28/5/08 by Alez]


Alez - 28/5/08 at 08:52 PM

This pic shows the UN1 and NG9 side to side. The NG9 is a lot weaker (likely more suitable in terms of weight), but both look unsuitable because of their length

Found here (Renault Medallion = 21):
http://www.gt40s.com/forum/gt40-tech-powertrain-transaxles/19659-renault-medallion-transaxle.html Rescued attachment UN1.jpg
Rescued attachment UN1.jpg


cymtriks - 1/6/08 at 05:08 PM

From the original post I think what is wanted is a cheaper transaxle than a Porsche G50 that can be inverted.

I have looked at several forums and done a search for this but apart from the G50 I cannot find any examples of a smaller transaxle being inverted.

The VW Beetle, Renault UN1 and the alfa transaxles are all getting on a bit now. They may well be up to the job but finding one might be an issue!

The obvious choices are:
Audi (which I can find nothing regarding inverting) and Porsche (which can be inverted but it is big, heavey and expensive) and Subaru (not common in 2wd)

Does anyone know otherwise?

[Edited on 1/6/08 by cymtriks]


mr henderson - 1/6/08 at 05:29 PM

quote:
Originally posted by cymtriks

Audi (which I can find nothing regarding inverting)


Why would you want to invert it, though? It's already the right way round for a mid-engined car

John


Fred W B - 2/6/08 at 06:07 AM

quote:

Why would you want to invert it, though?



To improve the driveshaft angles with a low mounted (dry sump?) engine and a low ride height.

I've never seen or heard of it done on an Audi though.

In my car, with the RV8 sump flush with the bottom of the chassis and 80 to 90 mm ground clearance the drive shft angle is 10 degrees, which I am happy to try

Cheers

Fred W B

[Edited on 2/6/08 by Fred W B]


Delinquent - 5/6/08 at 01:43 PM

quote:
Originally posted by Fred W B
quote:

Why would you want to invert it, though?



To improve the driveshaft angles with a low mounted (dry sump?) engine and a low ride height.

I've never seen or heard of it done on an Audi though.

In my car, with the RV8 sump flush with the bottom of the chassis and 80 to 90 mm ground clearance the drive shft angle is 10 degrees, which I am happy to try

Cheers

Fred W B

[Edited on 2/6/08 by Fred W B]


& if you are making the chassis yourself, why not angle the engine and box downwards a few deg to sit the engine lower in relation to the driveshafts (which is what is happening in my plan)


smart1275gt - 16/6/08 at 08:54 PM

I've seen Mazda rotary engines bolted to VW transaxles and cope fine upto 150bhp.

Rotary Sandrail Conversion

In a Mini - what's wrong with a rear engined transverse set up? I guess weight distribution, but that's it.

[Edited on 18/6/08 by smart1275gt]


sebastiaan - 21/6/08 at 06:49 PM

alfasud? this gices you inboard brakes also!



akumabito - 21/6/08 at 09:43 PM

Can't find any pictures at the moment, but perhaps the Alfa 33 box would be suitable?


sebastiaan - 23/6/08 at 05:51 PM

33 box is very similar to the alfasud box, but with outboard brakes. Highest powered 33 was the 1.7 16V, with 133bhp.

I don't know how they'll cope with 200bhp and middy levels of traction though...


akumabito - 25/6/08 at 10:08 AM

Seen a twin-turbo 33 once. 500Hp, kept shattering transmissions like crazy. I guess they'd be fine up to 200 though. This one claims 220Hp and 273NM with 0.8 bar boost. Think the 'box will be fine unless perhaps you mate it to a big V6 or V8.

Still not sure about the size though.

Mehh, stick with the Audi. It's a proven concept.


Delinquent - 25/6/08 at 12:10 PM

quote:
Originally posted by sebastiaan
33 box is very similar to the alfasud box, but with outboard brakes. Highest powered 33 was the 1.7 16V, with 133bhp.

I don't know how they'll cope with 200bhp and middy levels of traction though...


wouldn't really worry about the bhp... I'd be slightly more concerned with the torque figures...


Ratman - 27/6/08 at 04:48 AM

Remember that the transmission only has to be able to cope with the torque that can spin the rear wheels. In a light weight car this might not be all that much, so 500HP may not put all that much more stress on a transmission than 200HP. I guess it would depend where the weakest link in the tranny is.


thomas4age - 16/7/08 at 12:32 AM

the renault NG3 boxes aren't weak!

they cope with over 200hp in some formula renault cars over here..... everything in the cars has broken at least once exept the box.

it's small Light strong and has room for almost all 4 and 6 cylinder clutches you can think of..... cheap as chips also. all renault 25 exept the V6's and also all everything pre renault 19 uses them......

grtzx Thomas