Hi-Gear Engineering MGA Five-Speed Conversion – A Do It Yourself Adventure

There is no oil in the gearbox!

That’s the first thing I read upon receiving the four boxes that comprise Hi-Gear Engineering’s five-speed conversion for the MGA. Opening one of the boxes, I found the same message writ large: “THERE IS NO OIL IN THE GEARBOX!” And after removing the Styrofoam packing protecting said gearbox (just in case I hadn’t noticed) was the message: “Gearbox – NO OIL!

Okay, then. Consider me warned.

But apart from all the warnings, why am I converting my MGA to a five-speed? After all, there was a time when shifting a “four-on-the-floor” was the defining feature of sports car motoring (no three-on-the-tree for me!). But sporty or not and even in the best of condition, the four-speeds typically fitted to British sports cars had their shortcomings.

MG four-speeds, for example, are great for negotiating twisty two-lane roads where you can use them to advantage by more precisely modulating speed and torque. But in pretty much all the classic British cars I’ve driven on the highway, fourth gear just isn’t tall enough to cruise comfortably.

So when faced with a rebuild of the now-ancient three-synchro’ gearbox in my 1956 MGA (crunching ever-more unhappily from third into second), thoughts of a five-speed conversion started to make much more sense. After all, it wasn’t only the worn syncho’ rings that would get resolved; there would be other benefits.

For example, a lower engine speed on the highway should improve fuel economy, and may even keep the engine running cooler; I’d have a full synchromesh transmission and it would arguably produce less wear and tear on both the engine and the occupants.

True, a five-speed would not be original to the car, but my car’s not fully original anyway (somebody changed the front drum brakes to MGB discs at some point in its long history, for instance).

When it comes to choosing a five-speed transmission for the MGA, though, there aren’t a lot of options. Nonetheless, this is a well-worn path taken by many MG owners over the years, and the Ford T-9 (Type 9) gearbox used in the European Ford Sierra has been found to offer ideal features for transplant. It’s light, it’s compact, its ratios are compatible with the MGA and it has been readily available.

Unfortunately for North Americans, however, that transmission is very rare here. Used only in the short-lived and low sales-volume 1980s Merkur XR4-Ti (effectively a turbocharged European Ford Sierra hatch), sourcing a T-9 more realistically requires ordering from the U.K. where the Sierra was much more popular. Fortunately, the excellent kit available from Hi-Gear Engineering in England includes all the components (including a transmission, should you need one) necessary for a straightforward conversion. Cost for the MGA kit at the time of this writing is 850 pounds sterling, plus 675 pounds sterling for the rebuilt Sierra five-speed transmission. Shipping is extra.

Hi-Gear Engineering founder and owner Peter Gamble has been in the five-speed conversion business for over 20 years, now, and it’s a business that’s grown steadily. Founded in 1994 after modifying his own MGA 1600, the already retired Mr. Gamble discovered a new career duplicating his efforts for thousands of equally gearbox-challenged MG owners. Over time, he adapted his kit for the MGA 1500, the MG TC, TD and TF, the MGB (early and late), and the Magnette. He’s also ventured into Triumph territory supplying kits for TR2-TR6 models (for details, go to hi-gearengineering.co.uk).

Hi-Gear Engineering supplies kits to Moss Europe, Moss Motors, the MG Owners Club, Brown & Gammons and Frontline Developments. However, you can bypass the big suppliers and order one directly if you like. The affable and helpful Mr. Gamble – a genuine trove of information on five-speed conversions — is only a phone call away.

“It all started when I put one in my own MGA,” he recalls. “Then it turned out that a friend wanted one for his car, then another and another. Pretty soon my wife and I were in the transmission business!”

Happily for buyers of the Hi-Gear kit, Mr. Gamble is a stickler for precision and detail. Over the years he’s refined the component parts (which include a new driveshaft, custom bell housing, clutch release lever pivot, mounting brackets, gaskets, spigot bushing, modified gear lever assembly, clutch plate, gaskets and hardware) so that installation requires drilling only four holes to accept the new gearbox mount. The MGA clutch cover assembly, clutch release lever and clutch slave cylinders are re-used. You will be impressed by the quality of the packing and the parts you receive from Hi-Gear Engineering. No, I’ve actually understated that. You will be blown away by the quality of the packing and parts you receive, and the professionalism they clearly represent. No cutting, welding, bending or serious “persuading” is necessary for the installation, and that’s a direct result of the Mr. Gamble’s engineering savvy, high standards and comprehensive written instructions.

All that said, as you may know, removing the MGA (and MGB) transmission is an “engine-out” operation. Looking at it optimistically, here’s an opportunity to clean up your engine bay, easily install that radiator shroud, service the steering rack, re and re your carbs, gain access to several other hard-to-reach areas and components, and possibly work on your anger management.

On the other hand, it’s not a small job and you’ll definitely benefit from the presence of an engine hoist and one or two friends to help out. In my case, I was the student helper, and the two friends (thanks, Andy and Terry!) supplied the hoist and the expertise.

Except for a couple of seized bolts, wayward tools and learning to work by feel in some cases, it all went smoothly (although if child labor is permissible in your area, you may wish to avail yourself of some small hands on occasion). In fact, getting the engine out was easier than I expected, leading me to think that revenge would be exacted when we tried to put it back.

With the transmission out, the engine on a bench and everything ready to accept the new engine/transmission assembly, you can fit the beautifully machined replacement bell housing to the new transmission and after uprating the clutch plate with a new (included) MGB version, test-fit it while everything’s easily accessible. It should slide right in if you have everything correctly in place.

Once assembled, and after installing the new driveshaft and transmission (don’t forget to pre-install the two top bolts on the bell housing before pushing it into place) it’s a theoretically simple maneuver to lower the engine into the waiting transmission and onto its mounts. I should point out that you haven’t bolted the transmission to the frame yet (it’s supported by trolley jack at this point) as you will want to shift it and the engine to effect a smooth pairing.

This is when the temperature increased in the garage; the engine becoming surly and uncooperative, hanging from the hoist like a disinterested teenager, and apparently totally indifferent to hooking up with its new partner. Red-faced, focused and determined, with beads of sweat forming on his brow, at one point I saw Terry angrily reach for an ice pick and I truly feared for my inner fender.

When the ice pick failed, we were reduced to using a broomstick as a lever (Terry mentioned that Andy used to curl…), and I must say, that did the trick.

Now under the car, the transmission mount is fitted via four bolts through holes drilled into the chassis rails. It is challenging, especially if your car’s on jack stands, rather than up on a hoist. Hook up the clutch release lever and the job is pretty much done. You’re now the owner of a five-speed MGA!

Well, almost. Even after refitting the radiator, carburettors, electrics, speedometer cable (a new longer one supplied but a better option is to order an angle drive from Speedograph Richfield and use the original cable), exhaust, tachometer cable, gearshift with optional five-speed graphic, along with all the other sundry bits and pieces, there’s still one thing you need to do.

There is no oil in the gearbox!

Ah, the taste of engine oil. There’s really nothing like it, is there? Peter Gamble thoughtfully supplies two liters of the special synthetic oil you need for the Ford T-9. Pumping it into the hard-to-reach filler while on your back using a giant syringe builds character, for sure, especially as it drips all over your face. The good news is you only have to do it once. Why not do it earlier? Andy had warned us that you have to tilt the gearbox to install it, which will cause the oil to escape via the rear oil seal.

After bleeding the clutch hydraulics and getting feel back into the pedal, I was initially alarmed by the fact that the shifter wouldn’t move at all. Don’t worry. It’s because the gear oil hasn’t been distributed within the gearbox. Eventually you’ll engage a gear, then another, and after a spin around the block, all will be well.

And on the highway… Ah, bliss. The gear we’ve dreamed of is now available and your MGA settles into to high-speed cruising with a modern, relaxed gait. A bonus is that the shift “feel” is close to that of the original gearbox, so other than the extra gear, the driving experience is largely unchanged.

A lot of people want this kit, and here lies the irony. As time passes, demand is exceeding supply. The bell housing, driveshaft and fittings are no problem as they are custom made, but the gearbox itself is, as they say in England, is getting “thin on the ground.” They were current in the 1980s, after all, and as Peter Gamble says, “We’re seeing less of them, and when we do, they need significant work.”

As time passes, however, the availability of the Type-9 gearbox will continue to decline and eventually, supply will dry up and a more modern and plentiful alternative will be required. One promising option is a kit under development by Vitesse Global Ltd. (vitesse-ltd.com), another British company specializing in niche engine and transmission products. Established in 2012, the company has a supply contract with Mazda for the five-speed transmission from the outgoing MX-5 and is already offering a full conversion kit for the MGB.

Key differences between this and the Hi-Gear kit are that the transmission is more modern and is brand new. No cutting, welding or drilling is required and Mazda has committed to supply the gearbox into the future. An MGA kit was announced a couple of years ago, prototypes are in cars, with production in Q1 2018. Kits are also available for MGAs fitted with an MGB engine. See link below.

The good news is that it looks like our vehicles are being well served by specialist suppliers. That’s a result of classic MG’s continuing popularity and the determination by owners to keep them on the road.

Hi-Gear Engineering

Vitesse Global 5-Speed Conversion


    • Jeremy on April 14, 2018 at 3:46 pm
    • Reply

    Hey Paul. Very informative read. Just wondering what the engine rpm is now at, say, 100 km/h.

    1. 2800 rpm at 100 km/h.

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