Mazda MX5 BP 1.8 motor and gearbox swaps. Gearbox mountings

[ewokracing]

hi guys

those of you that have done the miata/MX5 swap into things like Escorts and Triumphs, how did you mount the gearbox?

I know that normally RWD Mazda gearboxes have a mount underneath the box, but mx5 ones have the mounts on the side.

I was hoping that I could use something like a Mazda Bravo/B2200 etc gearbox instead, but I think that the bolt pattern on the bellhousing is different.

thanks

(oh and some pictures of how you did it would be awesome).

[wheelspinner]

Hate to contradict you Mx5 gearboxes don't mount on the side.....
They have 2 huge bolts go from top to bottom through the box that attach it to the power plant frame and behind,heading towards the rear of the box, that they have a sort of L shaped bracket with a captive nut that locates onto the ppf.

www.mx5cartalk.com/forum/viewtopic.php?f=29&t=30535

Could try something like this

mx5-haynes-roadster.blogspot.co.uk/2011_07_01_archive.html

Might need to shorten the shifter to get it in the right position

www.classic-ford.org/cfp/m/tm.aspx?m=1704&mpage=6&p=9

[Seth]

On the drivers side I used one of the holes from the big bolts that wheelspinner mentions. On the passenger side I made up a small bracket to a couple of the casing bolts which sits on a rubber bobbin mount straight on to the chassis.

[goldnrust]

I had the reverse of this problem when I put the rotary in my mx5, and solved kit as some Mazda gearbox parts are interchangeable About 2/3rd the way down this page is all the info you need: www.solomiata.com/Drivetrain.html

Mazda uses the 'type M' gearbox in a number of vehicles made around the same time as the mx5. All type M boxes have the same mid section and internals, with different bell housings and input shaft lengths and different tail housings and gearbox mounts. You can take a tail housing from a series 2, 3 or n/a series 4 rx7, or from a b2000/2200 and bolt it straight onto the back of your mx5 box as a direct swap.

One note about the info on that site, is the speedo drive info is a slightly wrong as you need to be more careful of interchangeability than they say. I learnt the hard way when I couldn't work out why my hybrid mx5/rx7 gearbox was chewing speedo drives up!

Poor photo, but thats a series 4 n/a rx7 gearbox on the left with it's tail housing off with normal gearbox mount, and a mk1 mx5 gearbox on the right. As you can see they are identical, and I bolted the mx5 tail onto my rx7 box and it worked perfectly.

[ewokracing]

Mar 30, 2014 7:31:25 GMT wheelspinner said:

Hate to contradict you Mx5 gearboxes don't mount on the side.....
They have 2 huge bolts go from top to bottom through the box that attach it to the power plant frame and behind,heading towards the rear of the box, that they have a sort of L shaped bracket with a captive nut that locates onto the ppf.

www.mx5cartalk.com/forum/viewtopic.php?f=29&t=30535

Could try something like this

mx5-haynes-roadster.blogspot.co.uk/2011_07_01_archive.html

Might need to shorten the shifter to get it in the right position

www.classic-ford.org/cfp/m/tm.aspx?m=1704&mpage=6&p=9

thats what I meant with the side mount, that big frame thing that runs to the back end of the car.

Anyway, I just saw in someone's herald thread that there are two tapped holes by the look of it under the extension housing:



Depends on length etc, but that will solve my problem nicely.

I had a Series IV turbo gearbox in this car with the 12a and it bolted straight up to the crossmember, Nice to know I can mix and match gearbox rear sections to bellhousings if I have to.

[wheelspinner]

Apologies thought you meant mounted on a rubber mounting.

Yep there are two holes just behind the ppf holes i think they are m10 if you look on thta exploded diagram i posted it attaches the L shaped bracket to the ppf.

I have a spare gear box in the garden if you want me to do some measurements.

Steve

[goldnrust]

That solution you've posted looks good.

Just to confirm, the rx7 series 4 turbo box is a different box, its the series 4 n/a box that shares it's internals with the mx5 one. Also switching the tail housings is easy, switching bellhousings is quite possible but you've gotta watch the input shaft length.

[mhuk]

Land rover mount on end of g/box bit like the above pic

[ewokracing]

^ read my mind, I swapped the engine mounts in my p6b about 3 years ago and they looked pretty sturdy. They're similar to Mazda rotary/early piston mounts too.


I've run into another problem though. Apparently the sump bowl will hit the drag link in my 1300. I've searched for hours but haven't found anyone who has cut and welded a B6 or BP sump for extra clearance at the rear. Plus the gearbox bolts to the sump. Hmmmmmm

[wheelspinner]

How much clearance do you need...if you drop the sump there is a baffle on which the oil pick up sits,that sits in a baffled hole

www.mx5nutz.com/forum/index.php?showtopic=7079

So you might get away with notching the bowl but chopping it about too might prove a bit of an ordeal

What about a v6?

forum.miata.net/vb/showthread.php?t=434146&page=2

Claire at curse word Engineering (yes thats her company) does some great conversions on 5's

Steve