MX5 Donor, Using as a Donor/problems/solutions/advice Info

[CTWV50]

Originally Posted by Talonmotorsport

If you remove the MX5 rear diff cover and the mounting arms you can make the MX5 diff fit where the Sierra one would go. You would just have to alter the wishbones to take the MX5 uprights.

Hi phil,

I've just discovered you absolutely can't use escort track rod ends with mx5 uprights.

http://www.haynes.co.uk/forums/showthread.php?t=12605

Just clicked on your shop link and noticed your selling extensions for mx5 steering balljoints. Is that right?



Cheers

Chris

[PorkChop]

Originally Posted by CTWV50

Hi phil,

I've just discovered you absolutely can't use escort track rod ends with mx5 uprights.

http://www.haynes.co.uk/forums/showthread.php?t=12605

Just clicked on your shop link and noticed your selling extensions for mx5 steering balljoints. Is that right?



Cheers

Chris

Yes, it is Chris. I have a pair on order from Phil

[CTWV50]

So what kind of gearbox to prop flange clearance are people leaving? As there is no PPF anymore there is likely to be substantially more movement on the splined end of the prop. Any ideas?

[Talonmotorsport]

Originally Posted by CTWV50

Hi phil,

I've just discovered you absolutely can't use escort track rod ends with mx5 uprights.

Cheers

Chris

Why would you use Escort track rod ends with MX5 front uprights? The Mazda track rod ends are kinked for use with the angled steering arms on the uprights, the rack extensions that I make for MX5 builds have M12 threads for Mazda rod ends.
There is a post on here some where from me about making the lower front wishbones bent so that the steering arms on the rack clear them.

[robo]

Is that kick in the lower wisbone a good idea? It has to be compromised in strength with the set in it and the angle of that tortured track rod end looks less than comfy. I am not knocking it but merely pointing out that from an engineering point of view its less than ideal. It might just be the angle of the shot.

Bob

[Talonmotorsport]

That's the correct MX5 track rod end for the MX5 upright although I don't think it had the top wishbone in place.
I take on board what your saying about the bend and it's been discussed before but it's done with a 25mm tube former so it's as clean as the bend can be.
I looked at the bend in the lower wishbone and came to these conclusions:
the chassis bracket is welded to a 1.5mm walled box section in some cases
the load acts on both ends of the wishbones not in the middle, if any load is transfered through the bend the pivots have siezed
if worried up the material to 3mm wall

[CTWV50]

Just thinking about this wishbone clearance issue. What about putting the lower wishbone chassis brackets beneath the Bottom rails rather than on top. How would that affect things? Might order 4 and try it out as an option.

How's that batch of mx5 steering rack extension coming Phil?

[Stot]

Originally Posted by CTWV50

Just thinking about this wishbone clearance issue. What about putting the lower wishbone chassis brackets beneath the Bottom rails rather than on top. How would that affect things? Might order 4 and try it out as an option.

How's that batch of mx5 steering rack extension coming Phil?

Don't think that will be possible.
You would need quite a steep upward angle to keep the upright in the correct place and this would foul the chassis on bump.
The Wishbone would need to be longer.
The lower ball joint would be canted all the way over, locking out on bump.
Also there's no where to put the forward mount on the bottom as its mounted to the angled FF members.



Cheers
Stot

[CTWV50]

Oh yes! Not one of my better ideas. lol!

[vmax1974]

Just about to move onto mounting the engine into the chassis what height have people mounted there engines to allow for clearance of steering

I am using the 1.6 engine

All advice greatly appreciated