lsd or not! and if yes...

[Rodolfo]

Hy!
I have a 016 aaz on my cav, i do not know if it is a good idea to change the open diff with an lsd. and if yes what kind of lsd. (ex porsche or quaife or...) Please tell me somethings about your experience.
On my Birkin seven is a must have add, but on a gt40... i have not the necessary experience to answer this question.

It is necessary to have a zf on a 380 cv motor?
I will use the gt on the road and sometimes in Monza race track!:thumbsup:

R

 

[Cliff Beer]

Hello R,

Do a search for "016" and you'll find some threads on this. Basically, some folks have had success putting in an LSD from a porsche 944 turbo 016 box. And, I've heard the quaife LSD is good too. Off the top of my head I believe the quaife is a worm-drive/torsen type LSD whereas the 944 LSD is a plate type - there are pros and cons to both (and a thread or two here on that topic as well).

Your AAZ doesn't have the best ratios for faster european style driving. There are better 016 boxes with more desirable gear ratios. I have attached an 016 gear ratio worksheet here (created by Ron Earp I believe) for reference. I believe the "3U" coded 016 with much better ratios is available in europe only (not US) so that's the one I would be looking for if I was you.

One other minor note on the 016 box, there's a strengthening plate that can be added to the rear of the iron housing as a improvement to structural strength and durability of the box (it's not a very strong transaxle). These guys sell a kit: http://www.auditransparts.com/7794.html And, I have also attached a pdf of the installation process if that's of interest.

Good luck!

 

[Rodolfo]

Cliff thank you AGAIN!
I have read something about the porsche lsd, but it is not too easy to find and i prefer to buy a new quaife. But i do not know if i MUST have an lsd on a gt40.
Do you have an lsd on your gt?
Tell me what do you think about this upgrade.

Grazie Cliff!

 

[AdrianBurton]

From what I hear if you are serious about racing/ street performance then the LSD becomes more important, but if you are only going to the track on rare occasions AND drive on the street like you would a passenger car then I would pass

 

[Paul Thompson 'Hooligan']

For what it's worth - I've driven 40s with Pawl locker type, Friction plated type and Quaife ATB Torsion type differentials and the Quaife unit was the best suited for both road and track IMHO.

When we first fitted the Quaife unit to Roy Smart's Mk1 GTD40 (UN1 / 450ish BHP), it transformed the handling, allowing much more power to be used both off the line, through corners and out of corners. The best bit of all was that it removed the tendancy for the back end to break away quickly when cornering hardish, which whilst it could be caught with quick reactions was far more easily controlled with the ATB. The car would instead start to move into a gradually increasing oversteer condition/drift, which made it a blast to drive in the wet and was definately a safety enhancement I think both on road and track

Just my own experience/thoughts... others may differ in opinion.

 

[Cliff Beer]

Cliff thank you AGAIN!
I have read something about the porsche lsd, but it is not too easy to find and i prefer to buy a new quaife. But i do not know if i MUST have an lsd on a gt40.
Do you have an lsd on your gt?
Tell me what do you think about this upgrade.

Grazie Cliff!

Hi Crudo,

I would wholeheartedly agree with Paul. Yes, it makes a big difference.

Primarily this is so on a GT40 because the high levels of torque of the SBF can create a LOT of wheel spin of the less-loaded wheel in a power-on situation. And, during hard stopping where some braking force is generated through engine drag, the LSD applies a more even amount of brake to each wheel thereby.

Personally, I'd go so far as to say that any track time at all calls for a LSD. I wouldn't want to be on the track in my GT40 without a LSD. Sure, you can do, it's just a lot more pleasant (and safe) with a good LSD. My preference is for the torsen worm drive type LSD and I will be installing one of those soon. Street work doesn't necessarily call for an LSD, but who doesn't want to burn 'em off once in a while when you have a safe bit of road? A one wheel burn out is a bit funky.

 

[AdrianBurton]

I agree with Cliff and Paul on that, I am going to install one in my car as well, but my plan is to use the Kaaz LSD in my build

 

[Rodolfo]

Hy Adrian what kind of transaxle do you have in your gt?

I'm thinking to swap my 016 for another stronger gearbox, but i do not wanto to spend 10000 dollars.
Any Idea?

 

[Jack]

IMO, I prefer an LSD in any car as light as ours and having 400HP or more.

 

[Howard Jones]

A LSD is the most effective performance improvement you can make to a GT40 with the exception of tires. I have a Quaife TBD in my UN1 Renault and it completely transformed the car on track and at the same time it has no detrimental effect on street driving. Its just in there and works all the time without any drama. Magic!

As far as Audi's, I don't think they are weak by any measure. They just will not stand up to repeated abuse (what will). Most good condition Audi's should be good for up to 400hp IF you are a mechanically sensitive person and drive it like it is YOUR money.

Should you intend to change it for something else you might look into putting a G50 XX into the car with a Quaife installed. I think it can be done for a modest amount of money if you don't spend a lot extra on custom gears and such. You are in Europe so maybe you can find a good deal on a used Porsche gearbox /flywheel/clutch, etc.

I am not clear on your engine? If you are saying you have 380HP then the Audi should be fine. How about installing a Quaife unit in it ? Or fine a better suited Audi and upgrade it with a Quaife. This will save you some money on the other conversion part and you won't need to rebalance your engine because you can reuse your flywheel and clutch.

I do agree that any light mid-engine car with more than 275-300hp should have some form of LSD when on track.

 

[Rodolfo]

I have a 302 with, as the seller told me, 380 cv. It is good to hear that my audi016 can support my engine. i am a little in alarm about the audi gearbox...

But if this transimission may be used i will buy the strengthening plate and a lsd from quaife.

Grazie!

For info, i can find a g50 for 1000 euros.

 

[AdrianBurton]

Hy Adrian what kind of transaxle do you have in your gt?

I'm thinking to swap my 016 for another stronger gearbox, but i do not wanto to spend 10000 dollars.
Any Idea?

I have a 01X 6spd from a diesel. I am not building a GT, yet I am doing a V12 powered Diablo

SDC10458 on Flickr - Photo Sharing!
SDC10457 on Flickr - Photo Sharing!


If you are not going to abuse your car the 016 will do just fine. I went with the 01X because it has better ratios and they are cheap enough that I could simply replace instead of repair if it goes BANG

 

[Randy V]

I decided - for now - to stay with an Open Diff in my G50/03 for a couple of reasons;

1) Cost
2) Reduced strain on the gearbox. Should the rear tires decide to really hook up hard during a peak torque operation with an LSD, the gearbox will be under great pressure.

Interestingly enough - I don't think that an LSD is entirely warranted in these cars as they are so light. Why you ask?
In the early 70s I campaigned an old front engine Top Fuel Dragster. The differential in this car was an Open differential with 4.88:1 gears from a 1957 Oldsmobile.. The car never failed to light up both rear tires during the burn-out. Nor did it ever light up only a single tire if they broke loose on the launch.
Also - David Bordon (on the ffcobra.com forum - link below) autocrossed his FFR GTM with the same transmission as I have and found that even in the really tight corners with full throttle on exit would not spin just one tire.

I submit that the cars with little weight (such as these) will force the side-gears in the differential out into the carrier "hard enough" to lock the axle under many/most circumstances..

Now - when traction is limited or compromised under one tire and not the other, I do believe that this will be the only tire to spin.

I'll give my current setup a go and see how it works and report back the results..

to LSD or not to LSD this is the question - FFCobra.com - Factory Five Racing Discussion Forum

Food for thought...

 

[Paul Thompson 'Hooligan']

Interesting line of thought Randy and I can understand your reasoning behind it BUT experience of the 40s, or at least those with stock UN1s without LSD does show major improvements with the ATB diff fitted.

I remember well watching video of Malcolm MacAdam competing at Prescott in his GTD40 with stock non LSD UN1 and each time out of a slow climbing tight left hander, oh tarmac - it lit up the lesser loaded wheel - big time.

It was also a regular occurance for the cars at Wiscombe Park to struggle out of the tight hairpin at SawBench - with sap from trees and the odd shower, the cars would almost stop there, scrabbling for grip.

After fitting the ATB diff for Brighton 2001, the difference was marked. In 2002 at Longleat would record a 0-60mph of 3.7s / 0-100 7.6s and progress out of corners was significantly improved. I think ALL competitors thereafter, fitted ATBs over the next few years, but in 2002, I won 8 out of 10 events coming 2nd in 2 whilst setting several class records that stand today. I don't attribute this to my ability - I attribute a fair proportion of it to a strong Fontana based motor and the Quaife ATB diff transferring it effectively.

Thinking back, for trackdays, the best part of all was the back end being far more controllable/progressive in its slip than without the LSD - possibly the best £650 (then) spent on the car...

ps - would love to see some pics of your Dragster - how about posting some up in another thread.....:thumbsup: I would really really like to 'have a proper go' at drag racing one day.... definately on my list of life's tickboxes.

 

[Paul Thompson 'Hooligan']

Forgot to mention - !!

I agree with what you say Randy about hooking up well transferring damaging loads to other trans parts. Seems once you get over about 380HP - the stock Renault UN1s start to give real problems.

Firstly, a good hook up - or mid gear loading will snap the quill shaft. Happened to Malc pulling off at a junction and to Roy Smart, exiting a slight corner 'hard on it' in 4th!

Secondly, once you break traction and start spinning primarily a single wheel, the stock Renault diffs fail. The little planetry gears run on plain bearing shafts within the diff housing and spinning like buggery as you smoke a tyre, they overheat, expand the shaft, it siezes, snaps and then BANG! your diff goes pop. If you're lucky, you just lose power, (3GTDs I know of) if you're unlucky, parts of the pin exit the diff housing via the access holes and find their way between crown and pinion - result DOUBLE BANG!! - A lockup, cracked trans casings - oil everywhere - including on rear tyres - change of underwear usually a result!:laugh: (I know of 2 / 3 GTDs that suffered this too)

ALL UN1s with stock non LSD diff.....

 

[Rodolfo]

4 Questions!

1- A porsche 944 turbo 016 can be swapped without change my flywell and clutch?
2- A porsche 944 turbo is strongher than my 016 audi?
3- What I need to swap my 016 for a 930?
4- The 930 short version is always without an lsd?

Thank you very very much for the info and sorry for my english...
;-)

 

[AdrianBurton]

4 Questions!

1- A porsche 944 turbo 016 can be swapped without change my flywell and clutch?
2- A porsche 944 turbo is strongher than my 016 audi?
3- What I need to swap my 016 for a 930?
4- The 930 short version is always without an lsd?

Thank you very very much for the info and sorry for my english...
;-)

1. No, the 944 does not have clutch provisions, but there have been those that have taken the gears from the 944 case and installed them in the 016

2. The gears and bearings in the 944 are thicker/ stronger

3. You would need a new adapter kit

4. Not sure about that one

 

[Rodolfo]

Where i can find a kit to use a 930 on my 302?

 

[AdrianBurton]

California Motorsports - Porsche transaxles, gears, differentials, parts and service
Kennedy Engineered Products
Renegade Hybrids

Are the ones that I know of in the US

 

[Rodolfo]

Grazie Adrian!

If somedoby needs parts for alfa romeo/autodelta i'll be happy to help!