Hi Leon, I've been looking at your progress on the gearbox, nice work! How far along are you with the car? I'm working on a Lola T-70 MK3-B (street runner) and I also have a McLaren M-12 GT project car! The M-12 GT will be a Track/Street car with about 650+ HP so I'll be looking for a strong gearbox for it. Thinkin about a Porsche 930 or G-50. Are you going to offer your creation for others too? Just thinking outloud... :coolgleam:http://www.gt40s.com/forum/images/smilies/coolgleamA.gif Panama G... Ps, I just got another Lola T-70 MK3-B body and frame, this one will be a track only car... (maybe ;-)
Custom transaxle
- Thread starter leonmac
- Start date
hi Panama G,
Those are great cars you are working on, true 60s icons. I'm a fare way along with my car, I have pretty much finished the tub and suspension but as with all these types of projects you tend to change and redo things as you go. As for the transaxle and some of the other parts I'm casting, Uprights, wheels etc it would be nice to get some comercial payback but that is a fare way off. My short term plans are to get it to a workable prototype and then think about where to go from there. Cheers Leon
Those are great cars you are working on, true 60s icons. I'm a fare way along with my car, I have pretty much finished the tub and suspension but as with all these types of projects you tend to change and redo things as you go. As for the transaxle and some of the other parts I'm casting, Uprights, wheels etc it would be nice to get some comercial payback but that is a fare way off. My short term plans are to get it to a workable prototype and then think about where to go from there. Cheers Leon
I have heard on more than one occasion that the R230 is like a Ford 9 inch rear, but stronger, and with IRS
The R230 was also found in the Infiniti Q45.Ian
Love the work and the prototype so much that I decided to try a transaxle fabrication project of my own. See the new thread: New/Old transaxle ...
Calif.Fogg
Calif.Fogg
Been awhile since last post and have had a set back with the original mock up so have now made a completely new mock housing, this one is much more stout and will be easier to have cast although it will be a bit heavier. I have tried to go away from the 3rd shaft for the pinion and QC gears (will make the housing 2'' shorter and lighter) but its hard to find a diff that will let the input shaft run under the carrier while only having 3.5" shaft centres. The ford 9" carrier would be ideal but the pinion height still makes it hard. I have thought about adapting the R230 R&P to a ford carrier?? Or just run a spool?? this is for a track only application. any thoughts. Cheers Leon.
Great project, I had a brief play about with a home grown transaxle, I initially based it on the internals of a wc t5 and cosworth diff. There were problems with my concept similar to yours with shafts passing over the diff and pinion height, it all got a bit to complicated to be feasible. I then looked at using a jag lsd diff (4hu) with 4 speed top loader internals, that was doable and had the advantage of having the room for changeable drop gears at the back of the car (hewlandish ) . Anyway the G50 emerged at the same time which seemed to tick enough boxes so I stopped playing with the project and messed with that instead.http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/40490-g50-not-flipped.html
Bob
) . Anyway the G50 emerged at the same time which seemed to tick enough boxes so I stopped playing with the project and messed with that instead.http://www.gt40s.com/forum/gt40-tech-engines-induction-exhaust/40490-g50-not-flipped.htmlBob
You can get Chevy style gears for a custom Ford 9" carrier, i.e. they have less "hypoid", that is the pinion is closer to the centerline of the ring gear. They are intended for less drag than the Ford setup. Would that help?
Well I have spent a good amount of time on the T/A and have a final set up nailed down. This is what will be the final component list starting with ford 9" carrier with 8.8 R&P The gear box can house a ford Toploader gear set but the first one will have the Nissan 4 speed gear set which is almost identical diamenssion's to the Toploader I have set the input shaft at 2" below the axle centre line and the pinion height is 1.5" above. The out put shaft will run Winters QC gears to the pinion shaft. I have almost finished the mock set up and now working on selecters. The length of the complete box from bell housing mating surface to rear is 25" and from Axle centre line to rear of casing 18" this is 2" shorter than a G50. I have decided to go with the 3rd shaft for the pinion for 3 reason's 1) using the QC gears will make the unit more usable for different weight and power cars, 2) it makes it easier to set up the pinion and the input shafts and 3) I can run the 3.5" shaft centres which makes getting the input shaft under the diff carrier easier. Will have photo proof for you all shortly. I'm feeling really pleased with the progress and would like to see it in alloy before the new year but finance will decide that. Cheers Leon.
I do believe they are available in ratios in the 3.00/3.90 range. I just found that page quickly to show how they do the gears.
The 8.8 comes in 3.08 and up, using the QC gears I can use any of the available R&Ps up to 4.1 so it gives good flexibility Not everyone has a 500+ cube engine and wants 200mph this is the main reason I went for the QC option. It was that web site I got the info about the 8.8. and JacMac's guidance that decided the final component choice.
Did a couple of hrs in the work shop today working out selector positions and fitting the reverse idler shaft and gears. I'm now at a crossroad, Casting the diff housing is a given but I'm now thinking for fabricating the gear case. the plan is to laser cut the end plates that hold the bearings then using tube cut to precise length and studs that will sandwich the end plates and then fill in the casing flat plate. My thinking is that the end plates and studs do all the work and the side's main purpose is to hold the oil in. That is a very simplistic view and obviously the side's as such also provide a great deal of the strength. The other option is to continue with the mould and cast the main case. anyway I have taken some photos and hope you can get a rough idea as to where I'm heading. Cheers Leon.
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I have some photos of the GM adapter and the Hewland Adapter that I made so far just need to make a Ford one. They press onto the spigot on the front of the housing, the Hewland is held in the correct position by the piece's on the side which also become strenghtening once cast the GM still has to have the centre routed through and it will also then locate in a fixed position. I have poured the first piece in Alloy (rear QC gear cover) and hope to pour the Diff section next. The gear case itself is still under reveiw. 
At this stage I plan to cast the Bell housing adapter as part of the diff section so it wont be a seperate piece that is bolted on later. cheers Leon
At this stage I plan to cast the Bell housing adapter as part of the diff section so it wont be a seperate piece that is bolted on later. cheers Leon
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Well I have poured the first alloy for my Custom Transaxle and machined the case that it became. Its only a small part but it is better to start with the small parts and by the time you get to the big bits you should have things sorted. The part is the rear bearing retainer for the lay shaft and main shaft. There is a slight change in that this first T/A is only a 2 shaft and won't have the QC gears in the back this makes the box lighter and almost 3" shorter. From the Axle line to the rear will be 16". The area where the bearings sit is 15mm and the rest of the case is 10mm thick with the obvious ribs and bosses where the studs will attach it to the main case. Next part in line for casting is the diff section, once it is made then I can line up the other end of the gear stack and then I can make the main case. Anyway a couple of shots of the finished part. There is a casting that bolts to the back of this to cover and retain the bearings, I already have it I just need to drill and tape the holes, there is a provision to drive an oil pump off the back of the main shaft.
Cheers Leon.
Cheers Leon.
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