Talk Morgan Forums Morgan Sports Cars Classic Morgans (pre-CX) Flat Rad Morgan 5 Speed Conversions

So I just got a 1953 Plus 4 and am finding my way around. The previous owner always wanted to fit a 5 speed transmission in it somehow. Morgan Spares of New England has a Ford Sierra 5-speed conversion. Several of my friends have counseled me against the Sierra conversion (they don't like the trans), but I haven't found anything else available. Are there other conversions out there?

-Bill in Tehachapi, California

Bill, If the rest of the vehicle is original I would be tempted to keep the original gearbox unless you intend to do a fair bit of motorway mileage. What engine has it currently got?

Quaife, quaife.co.uk, do a fair range of gearboxes. I'm not sure that they go back to the 50s though.

As far as originality is concerned I think that any Morgan that is as original as it left the factory has never lived as a Morgan should

Presumable a Moss box car? Several owners have managed to fit an overdrive ......

It is the original Standard Vanguard engine with a single Solex carb. I live in California and have to drive at highway and freeway speeds quite a bit. I would like to drive 65 mph without the engine taching at 3500 for long periods... The car has a good Moss box in it (not too noisy).

I have a friend with a AH Bugeye Sprite with a Ford Sierra 5 sped in it. He complains that it just isn't that good of a transmission. Likewise, he has a MG Midget with a Toyota or Datsun 5 speed in it and says that it is a much better trans.

Bill,
I intend to get the Morgan Spares 5-speed kit for my 61 +4, as soon as I can spare $5,000 and two weeks of garage time.

You are right that driving your flat rad on interstates is going to be too hard on your engine. You may be aware that the Moss boxes on flat rads were "close ratio" boxes that had lower gearing than the "High ratio" Moss boxes that were fitted starting 1954.

A friend in Virginia has installed a Sierra 5-speed in his 67 +4 and he loves it. He does have some problems with the engine-to-transmission adapters, because he did not use the Morgan Spares kit, but instead modified a cheaper kit designed for a Triumph TR4. (The Morgan Spares kit is more expensive in part because it includes a royalty to the widow of the man who developed the conversion kit.) With Morgan Spares you get a kit that you know will fit and you know you can get expert advice.

Bill,

Will that engine make enough power at lower RPM to overcome the flat rad's air resistance at 65 mph?

If not, you may find yourself with a completely unusable 5th gear.

Many of these 5-speed conversions are coupled with an engine upgrade as well. You need power to push the air out of the way.

Warren

If you find the gear ratios very low have you thought of changing the rear axle to a higher ratio?
According to my workshop manual the +4 with the Vanguard engine had a 4.1 or 3.73 Salisbury. Not sure of the availability on crown wheel and pinions for your axle but it would have the advantage of keeping it standard and retaining value.
Moss box cars fetch a premium over here.

I believe the overdrive Moss box is a Jaguar item, but I know no more than that.

As JB Sports Engineering are probably the folk to go to for a Moss box rebuild, I cannot imagine they don't know what the overdrive options are.