Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Wolf Performance chassis bash guard

Plus 4 2019 with GDI engine and Mazda gearbox. The gearbox is more exposed because it sits in front of the crossmember. Was hit by a stone on a dirtroad. All still working fine after another 30'000 kms.
mog2 by Werni Wehrli, auf Flickr
mog1 by Werni Wehrli, auf Flickr
Mog by Werni Wehrli, auf Flickr

It’s a shame we have lost Simon. I’m sure he would have easily supplied something like this to fill the a gap, if there was demand.

That’s a very smart looking plate.

Some queries :
What’s it made of and how is it attached?
The underside looks to be slightly lower than the base of the gearbox housing - thus increasing the chance of impact?
Wouldn’t the energy from said impact be transmitted to whatever fixes the plate to the housing and thus to the housing itself?
Any mileage in cutting off the portion of gearbox that protrudes below the sump?

Reason for asking is I looked closely at this while under the car not long ago, pondered the big cut but subsequently chickened out.

Thanks Chris.

What’s it made of and how is it attached?
It’s made from a 300 series stainless, although aluminum would have been fine.
It’s attached with a single M8 socket cap. It’s probably over the top but there is a small protruding ‘heel’ step on the back mounting face, in an attempt to bias the thin front portion of the deflector hard up to the sump casting when the bolt is tightened.





The underside looks to be slightly lower than the base of the gearbox housing - thus increasing the chance of impact?
The deflector is exactly the same thickness as the gearbox step at the center, so the midpoint ground clearance has not been reduced.




Wouldn’t the energy from said impact be transmitted to whatever fixes the plate to the housing and thus to the housing itself?
Hopefully owing to the deflector’s angle, some of the impact energy will now get transferred to lifting the car/engine. However the bottom line is, the deflector is attached to a reasonably strong part of the gearbox casting and is sat on the very stiff vertical edge of the sump casting. I’m happier now with it in place, compared to how the car left the factory.

Any mileage in cutting off the portion of gearbox that protrudes below the sump?
Like you, I pondered long and hard about cutting that protruding portion off but decided it was a bad idea in the end. It could create a gaping hole through to the clutch assembly. Then I would have needed to make/fix a cover plate to keep the muck and wet out. It was much easier to attach the deflector. Once the deflector was on it also crossed my mind to lop off that little protruding lug on one side that you can see. But again, why butcher the casing unnecessarily. Should the lug ever be impacted, it will probably just snap clean off anyway. So no real harm done…

So does this deflector actually exist, or is it just an idea? If it does exist where can I source one?

I think it's good as it protects the gearbox housing which is more susceptable to damage that the cross member.

It can be mis-leading to purely look at what is the lower… gearbox or chassis.crossmember. I have had many hits on the crossmember but rarely on the gearbox. This must be because the gearbox is nearer the front wheels, so gets a better elevation when traversing sleeping policemen, whereas once the wheels are over, the crossmember then becomes the prime target, with no help from front wheels. Traversing at an angle sometimes helps but not always successful.
I have been tempted with bash plates but of course it reduces the ground clearance even more. When my tyres come up for renewal next year I am going for 65 profile all round instead of the standard 60. I am pretty sure it won’t noticeably affect gearing, and speedo is easy to adjust if needs be.

I went with the 65 profile on my plus 4 last year from the 60 as fitted by MMC. Primarily to add to ride comfort but also to take advantage of the slight increase in ride height and therefore ground clearance of an extra 10mm. I checked the speedometer against a sat nav device, road angel, and its reading was spot on! Hadn't checked prior to the change though, although I suspect it probably over read like most cars do.
For me the change has been greatly welcomed as the ride quality is improved no end and I wouldn't say the handling has altered detrimentally, certainly not for the road anyway. If it were a track car I would stay with the 60's as they are more urgent but I really am enjoying the car much more for general driving. Only disadvantage is changing all 5, however they are standard VW Polo tyre's so readily available and cheap for top branded options.

Feedback much appreciated. Although I changed all 4 road tyres in late 2016, my spare is OEM and so now 12 years old but never used, so not a bad idea to change it anyway.

Don’t hesitate Doug. 65 profiles tyres was about the first change that I did after getting the +4. As Sewin say, the speedo is spot on.

👍