Healey Scotland
The Scottish Sub-Centre of the Austin Healey Club Northern Centre
 

 

Five Speed Healey
By Neil Munn

If you are a fan of originality, you might want to turn the page now, If not you may want to consider the following.

Getting fed up with gearbox problems on my 3000, I decided to investigate my options. Either rebuild the existing box and overdrive or convert to a modern five speed. The overdrive had been "professionally" rebuilt a few years ago and was acting up sometimes. Had it been done correctly? Might I be throwing good money after bad?

A few companies seem to offer five speed conversions - either based around Getrag or Toyota gearboxes. I decided to go for the kit manufactured by Conversion Components of New Zealand - they were cheapest!

photo of Neil's MK1 Healey at the top of the "Rest & Be Thankful" - no link
What I received was a new alloy bell housing, a low mileage Toyota Supra gearbox, clutch bits, a propshaft joint and a new speedo cable. Oh, and sundry nuts and bolts and instructions.

With the old gearbox out and left to dribble oil on the garage floor, the first operation was to bolt the new bell housing into place and check the flywheel for clearance. Once this is correct (it was), the clutch is bolted up with the new Toyota clutch plate and the release mechanism installed. The new gearbox is then slotted in just as usual except that it is easier because it's a lot lighter, about 40lbs lighter in fact. I managed fine working alone as the new box balanced nicely on my trolley jack. The last few millimetres of bolting of the gearbox were fractionally tight but seemed OK. Certainly no warning bells going off but perhaps all these years of Healey blatt have taken their toll. The next task was to fabricate an inverted U section from 2.5mm plate to bolt onto the cruciform section of the chassis. As this section sits higher than the main chassis rails, there is no reduction in what we laughingly refer to as ground clearance. I drilled and tubed the chassis to accept 12mm dia bolts. I also fabricated a simple bracket to accept the tie bar (you know the one - it stops the engine fan mashing the radiator under heavy breaking). Next stage was to get a new propshaft made to mate Toyota gearbox to Healey axle. You do not need to chop up a Healey propshaft to do this. Incidentally, should I want, for some reason to change back to the original gearbox, the only change is two holes through the chassis and you can see them anyway.

With everything connected, it was time to fire up. Nothing. Just a loud click from the starter. Thinking that the battery was flat I tried jump leads etc, before realising that the engine would not turn. Gearbox out again. Xxxx. It was obvious that the clutch was fouling on the bell housing. A bit of relieving and a very careful check soon resolved that. I think that Conversion Components will modify their fitting instructions to take this into account.
With everything refitted it was time for final details. For my taste, the Toyota gearstick is too long and has a modern vibration damper fitted. Gentle heat soon took that off and left a stick just right. I also trimmed the glassfibre cover slightly. With the carpets in place, the interior looks the same as before.

Driving impressions. Clutch in; engage first gear - no baulking, no engaging second gear first, just smoothly in. As you start moving there is a strange noise, or rather lack of it. No first gear whine. Gear change quality is excellent, and the ratios seem to be nicely spaced with fifth gear very close to O/D top. The biggest surprise is the lack of transmission shunt, which I was not particularly aware of before. On my car the shunt may be worsened by a combination of high lift cam, triple HD8s and a lightened flywheel. Another advantage is said there is less power loss through the gearbox, meaning even more to the back wheels. My only loss is the lack of O/D third. I have always loved being able to flick O/D off to give you lots of passing power.

If you love thrashing your Healey and have gearbox problems then a five - speed conversion is a worthwhile option. Of course if you want to stay original you could always buy my old gearbox. If you have any questions, want to try the car or even want to buy my old box, please feel free to phone me on 0141 638 1614 evenings or e-mail me on tecbrick@aol.com. No abusive calls please, from concours fans! The contact number for Conversion Components is 00 64 7 863 8509 and fax is 00 64 7 863 6354. Remember that they are eleven hours ahead and I am just a satisfied customer.

PS. I am aware that my heroes at Denis Welch Racing reckon they have sussed the gearbox problems and I believe them but I've given them enough money lately.
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