Mazda rx8 gearbox

[Darren.]

Whilst looking through ebay I stumbled across this http://www.ebay.co.uk/itm/MAZDA-RX8-6-S ... ?hash=item and also this http://www.ebay.co.uk/itm/301772649057?ul_noapp=true.

Just wondering if this gearbox could be used for the moggy with some sort of adapter.
Any thoughts ?

[Chipper]

Probably. Just about any gearbox could potentially be fitted, assuming it will physically fit in the tunnel and you use an appropriate bellhousing adaptor to mate the engine to the gearbox, or have the skills to TIG-weld the Minor's bellhousing to a suitable ally plate to create an adaptor; folk have used Toyota, Ford, BMW E30 and various other gearboxes in Minors and other cars with A-series engines.

I recently heard about a Mazda gearbox conversion for the Minor available from the Morris Minor Centre, but I'm not sure which actual model of Mazda it comes from - MX5, most likely...

[firehor5e]

someone selling Rx8 gearbox £10 and rear subframe inc dif/brakes etc £20.Ebay. only 15 miles away from me in Devon.

[twincamman]

The RX8 box has the same input shaft dimensions as the TYPE 9 Ford box (1", 23 spline)

[Monty-4]

Somebody needs to make bellhousings and crossmembers for this conversion (JLH?)!

[philthehill]

http://www.ebay.co.uk/itm/Mazda-rx8-6-s ... SwZtJW9V4R

Unless there is a readily identified market for the conversion a manufacturer will not take up the proposal.

http://www.morrisminorowners.co.uk/view ... 50#p133105

See Sept 27th Post for details. Note that the engine is not an 'A' Series.

Unless you have a 1275cc (or larger) engine fitted I would suggest that fitting a 6 speed gearbox is way over the top especially if only a 948cc or 1098cc is fitted.

[Tootall]

The RX8 'box - especially the more recent 6-speeder - seems to be pretty popular with Ford types, as a replacement for the Type 9.

Apparently, as the number of splines and length of input shaft, as well as the length of the gearbox and position of the gear lever are the same, it's a pretty decent swap.

This is the chap who does kits; https://www.rx8gearboxadapters.com

He doesn't make them yet for A series engines but is always looking to expand his potential market.

It seems that 5th is direct drive (making 1st about as redundant as a Minor 1st gear) while 6th is over-driven.

Mazda boxes seem to be around £300 on eBay, rather than the £600 for a Type 9.

Ford types tend to use the carbonfibre Mazda prop, with a custom-made rear joint.

It might be the new 'Type 9' for anyone looking for longer legs on the Motorway...

He's posted more information here: http://www.turbosport.co.uk/showthread.php?t=980905

[Tootall]

Still thinking about this...
RX8 Gearbox man is promoting them as a viable alternative to the Ford Type 9...

Which raises a number of questions:
Which clutch is used in a Type 9 - to - Minor conversion? The Minor one of a Ford one? If a Minor one, then presumably it can also be used for the RX8 conversion, too.

He offers a hydraulic clutch as standard - presumably a propriety kit to do a hydraulic conversion from a Minor specialist would be needed to make that work.

I assume the Minor starter goes with the Type 9 'box - hopefully it'd work with the RX8 too (would have to check where the Mazda starter is, relative to the Minor one...)

Is part of the Type 9 kit a new gearbox cover, to accomodate the different size/length? That'd need fabricating, if so.

The RX8 uses a carbon-fibre propshaft. In most Ford applications this needs shortening, which is possible, to fit a rear UJ, which would also need doing for a Minor.

If I'm going to the effort of doing a gearbox, it'd also make sense to fit something like a Capri axle, to help handle the power.

This will need a decent degree of work...

[Tootall]

Would also need to work out how to drive a speedo (unless using a GPS version - is that MOT legal?)

[kevin s]

The rx8 and lighter mx5 box have integral bell housings, you could make them fit to the engine by getting a new engine backplate made, here's one I did for the a mx5 box.

rps20210327_194402.jpg (127.38 KiB) Viewed 2598 times

We have tried it in the car but never got it finished, the issue with the mx5 box is finding a suitable clutch

For either of them you will need to cut a fair chunk of the clutch housing away to clear the steering rack and get a prop made, the other issue will be gearstick position, on the mx5 NA box you can move the gearstick forward to the minor position fairly easily, I don't think this is possible on the rx8 one .


Our plan now is to fit the mazda mx5 box to a maestro 1.3 engine, the mazda flywheel bolts to the crank on these resolving the clutch issue.

There is anther option, the suzuki box, barrat engineering do a conversion for the a series midget which addresses most of the difficult issues.

[Tootall]

The rx8 and lighter mx5 box have integral bell housings, you could make them fit to the engine by getting a new engine backplate made, here's one I did for the a mx5 box.

rps20210327_194402.jpg

We have tried it in the car but never got it finished, the issue with the mx5 box is finding a suitable clutch

For either of them you will need to cut a fair chunk of the clutch housing away to clear the steering rack and get a prop made, the other issue will be gearstick position, on the mx5 NA box you can move the gearstick forward to the minor position fairly easily, I don't think this is possible on the rx8 one .


Our plan now is to fit the mazda mx5 box to a maestro 1.3 engine, the mazda flywheel bolts to the crank on these resolving the clutch issue.

There is anther option, the suzuki box, barrat engineering do a conversion for the a series midget which addresses most of the difficult issues.

The more I think about this, the more possible answers come up.

A couple of things from your post - what's different about a Maestro 1.3 crank, compared to a 1275 crank, that allows you to bolt the Mazda flywheel to it?

Haven't heard about a Suzuki 'box conversion... will have to Ask Jeeves...

Type 9 kits don't have anything to re-position the gearlever mount, do they? But if the RX8 'box puts the lever in the same place, that might be OK...

I need to ask more questions...

EDIT: WOW! £3250 for the complete Suzuki kit... that's an RX8 box and £2750 of fabrication work... while the Barratt kit might be wonderful, it's too rich for my meagre 'budget'...

[philthehill]

The Maestro crankshaft has a deeper flywheel mount flange to accommodate a lip seal. The Maestro engine does not have a scroll to return the oil to the sump.
kevin s
What are you using to house the Maestro rear engine lip seal?
Phil

[kevin s]

The maestro uses a VW gearbox and clutch, coincidently this is 6 M10 bolts on the same PCD and crank flange diameter as the 6 MX5 M12 bolts so with a shouldered bolt and one hole opening up to a slot because one is offset they bolt up.

The plan for the seal is to machine the maestro backplate down to 18mm thick then bolt a backplate on the back of it to carry the gearbox, this will make the engine around an inch longer but with the front mount towers swapped and an electric fan this should fit easily enough.

[philthehill]

kevin s
Thank you for the above information.
For general info here is the Maestro seal mount/backplate:-

Maestro rear engine seal plate.jpg (414.94 KiB) Viewed 2099 times

Please keep us posted on how you get on.