333 gearbox rebuild

[jbz23]

Hi all

I have a bare 333 casing , wondered what my best options are to rebuild it ? . new 3 syncro mini spares straight cut kit ?? or any other kits out there ? any help or advice would be much appreciated

many thanks

jabez

[dklawson]

There are several people here who are quite versed in the early gearboxes and they will have the experience to comment on the straight cut gears.

Instead, I am curious about what you have to start with. Are the gears worn to the point they need replacement?

[jbz23]

Hi

No I have a complete but bare casing , no gears at all

Cheers

[CooperTune]

It's going to be a tough nut to crack. The first/second assembly is not included in the SC/CR kit. I haven't done a three synchro
in ages. If the first/second assembly can be purchased new, I'd suggest having the complete gear set REM treated to reduce noise.
The other thing I'd start looking for is shift forks. I have a fair collection of tranny parts. Steve (CTR)

[iain1967s]

If you are considering building it up to original spec using 3 synchro B type helical S gears, the only thing available new off the shelf is the 22G1100 laygear and the 22A1021 1st/2nd synchro hub. Everything else is NLA, so prepare yourself for an expensive international scavenger hunt to track down NOS gears.

Service parts such as bearings, shafts etc. are fairly easy to find from likes of guess-works, as most are common across all gearboxes of that era.

I just finished building one from scratch last year. I haven’t totaled up the numbers, but I’d guess I spent well over £2000 for all the individual parts, and that doesn’t even include a donor remote gearbox that I was gifted for the non-service related parts such as selector rods, forks etc.

[Dearg1275]

Have I not read a passing comment on here that it is possible to install a 4synchro gear set in a 3 synchro box. If that’s the case then that would give you more options. Others on here will know the truth of this.

D

[bwaminispeed]

Pretty difficult to do 4 synch into 3 synch box, as, the cases are quite different in the 1st motion shaft bearing area......

[iain1967s]

There’s a 22A982 1st motion and a 22A980 2nd gear on eBay currently, if you are still looking for a 1275 S gear set. These are usually hard to find NOS.

[Spider]

Have I not read a passing comment on here that it is possible to install a 4synchro gear set in a 3 synchro box. If that’s the case then that would give you more options. Others on here will know the truth of this.

D

That's not possible - without doing huge modifications to the case, the Mainshaft and Laygear is 1" longer for starters.

[Vegard]

Have I not read a passing comment on here that it is possible to install a 4synchro gear set in a 3 synchro box. If that’s the case then that would give you more options. Others on here will know the truth of this.

D

Nope, not at all possible.

[Dearg1275]

Have I not read a passing comment on here that it is possible to install a 4synchro gear set in a 3 synchro box. If that’s the case then that would give you more options. Others on here will know the truth of this.

D

Nope, not at all possible.

Just shows, you can’t believe all you think you have read.

D

[Maddog]

Well, yes it is indeed possible - but as Spider has pointed out only after some massive engineering and machining to make things fit. One day when I have the motor off the box in my race car I will have to post some photos for the disbelievers.

I can't take any credit for the hybrid gearbox - the work was done by the engineer who created the car. He liked doing things that people told him were impossible. He's still at it today...

[Vegard]

Have I not read a passing comment on here that it is possible to install a 4synchro gear set in a 3 synchro box. If that’s the case then that would give you more options. Others on here will know the truth of this.

D

Nope, not at all possible.

Just shows, you can’t believe all you think you have read.

D

Well, if you reweld the complete internals in a 3sync box, you can fit everything.... Why stay there, why not fit a motorbike 6speed dog. That has been dones as well...

If not, you can't.

Not trying to brag, but I guess I've rebuilt 40 Mini gearboxes the last 5-6 years.

[OzOAP]

Hi all

I have a bare 333 casing , wondered what my best options are to rebuild it ? . new 3 syncro mini spares straight cut kit ?? or any other kits out there ? any help or advice would be much appreciated

many thanks

jabez

I have just swapped over a 333 gearbox to a 4 syncro 1128.
333 has straight cut gear kit fitted. Customer was asking £1000 for it without the diff or £1300 with Salisbury LSD

[Spider]

Well, yes it is indeed possible - but as Spider has pointed out only after some massive engineering and machining to make things fit. One day when I have the motor off the box in my race car I will have to post some photos for the disbelievers.

I can't take any credit for the hybrid gearbox - the work was done by the engineer who created the car. He liked doing things that people told him were impossible. He's still at it today...

Nice !! Look forward to seeing that !!

Dave Rosenthal did a few 6 speed gearboxes. He worked from the 3 Synch Cases, only because that's what he had a load of to hand, however, as far as the case went, there was little modification done from memory.

[jbz23]

Cheers oz

I do have a 3 synchro straight cut kit in another 22G68 box , I guess there’s no reason I couldn’t put that into my 333 box ?

I guess everything size wise is the same ?

Cheers

[Vegard]

Cheers oz

I do have a 3 synchro straight cut kit in another 22G68 box , I guess there’s no reason I couldn’t put that into my 333 box ?

I guess everything size wise is the same ?

Cheers

Yes, go ahead!

[mk1]

Jbz, It hasn't been suggested, but if you are building a road car you would be as well off using a helical 3 synch kit from a standard Mini box as a straight cut one.

[jbz23]

Yeah that’s a thought mark

While we are on gearbox questions , what exactly is a 22G 1522 gearbox

Cheers

[Rusty old S]

1522 was the last generation 333, used in late mk1 s or early mk2 3syncro said to be a stronger case around the bearing area racers liked them in the day . Some early Ado 16s had them with different diff housing to suit robber remote