Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Extra ground clearance on a Mazda boxed +4

A quick bit of bodging this afternoon that I’ve been meaning to do for a while that maybe worth a post.

I’m sure anybody with this model is familiar with that shocking scraping sound a few inches from your bottom whilst negotiating some speed bumps (not to mention the embarrassment from any wincing bystander observing). The culprit will most probably be the low slung factory fabricated rear Mazda gearbox mounting arrangement extending from beneath the car. Its centrally located between front and back wheels incorporating two downward protruding bolts for maximum effect. A feature I don’t recollect on my previous Duratec with a MT75 box.

Here’s the culprit and this measurement is with an empty car, a good pair of springs and taller profile tyres than the standard fit giving about an extra centimetre of lift. Speed bumps can be up to 100mm high.


And shown here with the bolts trimmed back if you look closely. It was my initial attempt at a fix.


A little reconfiguration seemed appropriate so a couple of countersunk screws now fitted.




I should also be able to get over the pavement and drive into my garage with a greater payload too. Every little helps……

Mine has shorter bolts Rog.........

My bolts are similarly long to Rog’s but despite that, it seems that the chassis cross-member cops it every time. However, a useful mod. So what size screws were used and how do you manage to do up the nuts? (Have never felt around in that area so not sure what access is like.)

Access looks worse than it is. You can get a regular offset ring spanner in there easily to hold the nut whilst tightening with the alien key. I replaced the 5/16” bolts with a M8 x 25. It looks like one of these might be hidden inside the fabrication.
I’ve got grooves all along the pavement outside my property where bolts have gouged. It’s always been ‘a bit awkward’ saying to would you mind jumping out before I put the car away dear……

Excellent work Rog. The Plus 4's of that vintage was also a problem in Australia
The 2010 Roadsters were worse....

Thanks Rog for useful info.

A bit more undercarriage streamlining…..

This unfortunate mismatch between the Mazda bellhousing and Ford sump castings is a little disconcerting

Again only a feature on post 2010 +4’s. My previous 2006 MT75 bellhousing was nicely integrated and flush with the Duratec sump however this arrangement leaves a protruding step very nearly as low as the cross member. If the step ever took a significant clout the impact might get transferred to the diff/transmission. So as there was a spare hole in the bellhousing it seemed prudent to try a little deflector block the same thickness as the step.

You should see the mismatch on the S1 Roadster Rog. And it's lower than the gearbox crossmember, and there's a hole at six o'clock, which benefits from a cover plate!

Ouch! I was aware of the sump but not the gearbox. Don’t think I’d be able to get it out the garage if I had one of those.

The angle of this shot makes it look rather level, but the bellhousing is slightly below the crossmember.

I fitted a Wolf/BHM skid plate to my Plus 4, but here it wouldn't do much good.