Fitting a ZF Transaxle into Roaring 40s chassis

[Ross Nicol]

If your lucky enough to get your hands on a ZF and you have an RF car to put it in, my experiences here may help. I was told when I proposed to do this that "It won't fit" and my answer was I'll make it fit!
I decided to use an ERA bell housing and bolted it to the ZF then assembled the transaxle and motor.

Chassis Prep
------------
Removed engine mounts from chassis
Removed inboard suspension top link support

Clamped board to chassis under side and sat motor/transaxle
onto this board.The ERA bell housing has a flat bottom and sat flat parallel with the bottom of chassis.I decided this was as low as you can go.

Now for the fore and aft setting.I found the bell housing just cleared the crossmember nicely when the drive shaft angle was nice and shallow and where I wanted it.
I next bolted the engine mounts together and welded them back into the chassis.Finally I made brackets for mounting the rear and top of the transaxle. I removed the support board from under the chassis and there it was a ZF in an RF with minimal work .I have to say this work was carried out with no sump fitted as I had the dry sump fabricated to clear the front crossmember later.The motor was now lower (good for handling) and further forward (good for driveshaft angle).My goal was to achieve minimum chassis alteration and I achieved this goal to my surprise, It did fit didn't it Robert.

Regards Ross

[Ian K]

Question is - will Robert makes this an available
option ???

Ian

[Mark Worthington]

In order to minimize chassis alterations, I think the operative phrase here is "dry sump."

[Ross Nicol]

Mark
A friend of mine who bought one of the first chassis from Robert, has a 302/ZF combination fitted using a wet sump. The wet sump is very shallow and the wings make it difficult to access the solid engine mounts. he has to remove the sump before removing the motor.He had to remove
the crossmember from under the sump and also modified the chassis to allow clearance for the selector box on the side of the ZF. Geoff also has original Gurney Weslake heads on this car also. He has the motor slightly further forward than mine and as low as the bell housing allows like mine too. I can vouch for having the motor/ transaxle low in the car as I was following another RF on the track last saturday and he was very taily where mine was as solid as a rock. So it is possible to use a wet sump but a dry sump system is better in my opinion. Ian I'm sure Robert could
offer a chassis for fitting a ZF but whether he could make it affordable considering he is tooled up for the audi box is another thing.

Regards Ross

[Robert Logan]

Ross,
There are many reasons why cars behave differently and although some things change the car's behaviour it is not correct to say that the ONE change (lowering the engine) makes ALL the differences between the cars.

At Roaring Forties we have matched and usually bettered all the times that I have got from ALL other drivers with our FIRST car on road tyres.

The difference between your car and the car you are refering to can be summed up in a few areas and if it were as simple as you have indicated to lower the engine and use a ZF box than we would ALL be F1 champions.

There are two major problems with the other car :

1. the throttle linkage is like a on / off switch and I hope that the car will come to our workshop soon so that my staff can fix it, and
2. the car does not have a LSD fitted again soon to be fitted.

The driver has not got your experience and in my opinion has TO MUCH POWER with a 383 ci Ford with HUGE torque. I believe that the inside rear wheel is getting light and spinning up and when the wheel gets weighted up again she spins. The driver is gaining experience and is fully aware of his inexperience but is working hard and has lowered his times by over 20 percent in only a few months.

As regards to fitting a ZF gearbox into one of our Roaring Forties, Ross knows that we are working on this at present as we are working on a big block fit for a MkII , but as I have said before when it is ready then it will be released. If you want a car with something than ORDER IT !!!!!

We have just finished a car with launch control and traction control because they were ordered. I made a large number of adaptor plates because of all of the "I will order one of them" coments from the forum and guess what NONE WERE ORDERED.

My staff can do ANYTHING with our cars but I can not afford to waste their time and our monies.

Coming back to the topic of this thread, once the throttle response has been made uniform and controlable, the LSD fitted and the driver has a little more experience I am sure that his car will look a little more stable to your experienced eye.

Best wishes,

Robert

[Ross Nicol]

Robert
I obviously have offended you again. This was not my intention and if you look back through my posts I think you'll find they are very balanced. My post about the ZF transaxle and motor height in the car should have been taken as my opinion only as most readers would have. If I didn't have such a thick skin I would find your other remarks quite offensive. I have no intention of being confrontational but lie down I won't.

Regards Ross

[Robert Logan]

Ross,

Thank you for your kind comments about our cars and in particular the way yours handles. I supose we are both sensitive and stuburn and will always have an interesting conversation about everything. I would never expect you to fall down or go away as I would never expect anyone on this forum to do the same but please never expect anything less from me but to protect / support my other drivers / owners as I have done with you.

We are all GT40 fans, some have a lot more experience than others in a meriad of ways but we have the common thread in our lives which is our passion.

Please accept my appologies and I look forward to our next conversation.

To Ian K. - I am happy to build a car with a ZF box in it and like all other R&D projects, we will not charge for our thinking time only our doing time so the price will be similar to our standard car price. I must add that I believe that the OIE 6 speed Audi box looks a better box for road use.

Best wishes,

Robert

[patbarry]

Well said Robert!

[Ian K]

Robert,

As usual, you have demonstrated yourself to be very customer
friendly in listening to what is wanted and catering to those
desires if possible.

Ross,

I have found your threads on setting up your car and fitting
the ZF to be truly enlightening.

If I go the ZF route (which is where I am hoping to go for
various reasons), using a dry sump system is not out of the
question. I have found a local shop that makes custom dry
sump set ups - Armstrong Race Engneering http://www.drysump.com

Of course, it is all up to the finances and my financial
advisor (aka "The Missus") as to when this will all come
together [img]/ubbthreads/images/graemlins/smile.gif[/img]

Thanks as usual for everyone's comments and thoughts.

Ian

[Ross Nicol]

Ian
Thanks for the kind comments,I hoped that someone was benefitting from my ramblings. When I was researching the dry sump I checked out that site and their sumps look good.My sump has 2 scavenge ports. I think dry sumping is avoided because it's not very well understood and cost as well of course. I think, once understood a dry sump system is quite easy to understand with a multitude of benefits. As for the financial adviser yep I've got one too but I blew all our money before she found out and boy am I paying for it now.We are going for a drive on Sunday with the Lotus club,her first ride in the GT40 and I'll have to be on my best behaviour as any oversteer is not tolerated teehee.
Regards Ross

[Robert Logan]

Ross,

Enjoy the day, drive it like you stole it. Remember the "Men are from Mars" thing and understand that they will never work us out and dont let them even get close.

Financial advisor, YEP but leader of the OPPOSITION, ALWAYS !!!!!

Best wishes,

Robert

[super40]

I would love to see a pic of a engine in a rf mounted to a ZF gearbox. You can email me at mhorgan@san.rr.com for pics or post them here but you can attach one at a time. I'm thinking of a ZF because due to the hp and and torque of a 302 stroked to 347. Correct me if I'm wrong.

[TMR2003]

Is there a way to do it using a wet sump?

[Ross Nicol]

Mike
I presume you have read my earlier post detailing the advantages of using the ZF transaxle, and how it allows the motor to sit lower in the chassis.With the motor sitting lower in the chassis, the sump if not made shallower, would hang well below the chassis.A dry sump not needing depth is ideal in this situation but it is still possible to use a wet sump by cutting the bottom off the original sump and fitting wings to each side.The idea being to make the sump more shallow but still be able to carry the original volume of oil. The original race cars like 1075 had sumps with wings and pics are available in Trevor legates book in the parts list. I hope this helps and I haven't confused you.
Regards Ross

[Lynn]

Ross and Mike,

I have an inverted Porsche transaxle and, while I am not sure about this, I would be surprised if the ZF has your engine any lower than mine is. I sourced a wet sump, GT40 oil pan from Armando's Racing Oil Pans and it sits perfectly flush with the bottom of my chassis. The "wings" aren't that wide as this looks just like the original GT40 oil pans. It has built in scrapers and windage tray, as well as, a 4 trap door fence around the purpose built sump. It is very similar to the Aviaid GT40 pan (Armando worked for Aviaid for years before going out on his own.)

I don't know if anyone has tried either of these yet, but I feel relatively sure that they would work as a wet sump system with your configuration. I have pics of Armando's somewhere around here [img]/ubbthreads/images/graemlins/blush.gif[/img] if you are interested.

Regards,
Lynn

[Frank Catt]

We run a ZF Tranaxle in a GTD with a wet sump. I used a Canton 7.5 inch sump and have the bottom of the sump 1.5 inches below the chassis level, which means the bottom of the engine block is just 6 inches above the bottom of the chassis. We are then able to run IDA webbers with full length trumpets and still keep the tops of the webers below the rear window line. Even on some extremely rough events like the Isle of Man hillclimbs we have never scraped the sump on the ground. It can be done ! Frank

[TMR2003]

Is this using a Front or Rear Sump?

[Oliver]

This was very helpful for what I want to do. My question is RF still doing the converion on request basis only. If so, I'm In!!!

Regards
Oliver