5 speed conversion

[stuart_k]

I suspect from observing other posts that there will be 2 camps regarding this question.

I keep finding myself reaching for a 5th gear that isn't there. The traveller is used for weekend motoring, mostly A and B roads but we often travel several miles on a road which allows us to reach the heady speeds of 60mph and certainly between 50 and 60 there is a lot of noise and commotion. Next year we are tentatively planning a little tour which will almost certainly involve some motorway travelling and we certainly hope to make the National Rally which will involve a fair few miles of motoring.

Are there any advantages to a 5 speed conversion on a standard 1098 engine?

Would/should I need to change the diff or is that best left alone given that the majority of the time I'm driving around town and villages?

Does a 5 speed conversion require any structural changes? I'm ok with spannering but draw the line at structural changes - I've never welded and don't possess a welder (I know, I really should learn ).

Finally, what's it going to cost if I do the work myself (assuming no welding required)?

[PSL184]

My personnal opinion is to change the diff to a 3.9 and keep the standard 1098 box. The 3.9 is not as tall as the 3.7 so gives slightly more flexibility without a significant disadvantage at cruising speeds. 3.9's are also slightly cheaper than 3.7's. The 5 speed conversion if done yourself and you can source used parts, I guess would be around £300. A 3.9 diff is no more than £80.
You are probably gonna get a number of responses with other different opinions to follow.....

[bmcecosse]

Are 5 speed conversion not nearer £1000 ? I have the 3.7 diff (£70) with a warmed up 1098. It's great! As PSL suggests - a 3.9 may suit the standard engine better - but for the relatively tiny mileage you appear to do - I doubt if anything is 'really' worth doing.
Fortunately - you appear to have a very simple solution at hand. Just swap diffs with the Spridget. This will make the Minor slower and quieter (what you want) - and the Spridget faster and noisier (what every Spridget owner surely wants?) - all at absolutely no cost.
Ideal solution I would say ?

[cormorant]

I have the 3.7 diff in a standard 1098 and it's fine. Though I must say there are no huge hills in my area.
I wouldn't want to go further than this gearing though (well I would but the car wouldn't pull it I think)and fitting a 5 speed to a standard 1098 would do exactly that - might be ok on the flat.
So I'm sticking to the 3.7 and have plans to warm up the 1098 slightly.

[PSL184]

Are 5 speed conversion not nearer £1000 ?

Yes definately if you are buying new parts ie fitting kit circa £500 and recon box circa £400. However, T9 boxes can be got from scrapyards for £50 (they rarely go wrong (famous last words)) and the other bits required come up on ebay from time to time. My £300 was based on the potentially cheapest route but the safest / easiest would be nearer the £1000.

[mike.perry]

Isn't the conversion bell housing the expensive bit?

[PSL184]

From the MMCB website (other retailers also sell the kits).

FIVE-SPEED GEARBOX FITTING KIT (NEEDS TYPE 9 FORD GEARBOX) £379.00
A complete kit for fitting the Ford Sierra 4/5/6 speed gearbox to a 1098cc or a 1275cc engine. Different clutch combinations possible. Easy to fit with no permanent alterations to the vehicle.

[bmcecosse]

MMCB ? Does that include prop shaft/bellhousing/flywheel modifications/clutch plate/crossmember/mounts/modified gearlever/modified gearbox cover I wonder ?
I thought JLH did a complete 'kit' - but don't see one on their website - although there is a very comprehensive list of the parts required to do the job. http://www.jlhmorrisminors.co.uk/store/ ... at&catId=7 It adds up to quite a LOT, and I'm still not sure it includes everything.

[PSL184]

MMCB = Morris Minor Centre Birmingham.
All I know is that it says "complete kit". I couldn't find details of what was actually included..... ?

[charlie_morris_minor]

I have the 3.7 diff in a standard 1098 and it's fine. Though I must say there are no huge hills in my area.
I wouldn't want to go further than this gearing though (well I would but the car wouldn't pull it I think)and fitting a 5 speed to a standard 1098 would do exactly that - might be ok on the flat.
So I'm sticking to the 3.7 and have plans to warm up the 1098 slightly.

i do not fully understand your concern, the type 9 ratios are..
1st 3.65:1
2nd 1.97:1
3rd 1.43:1
4th 1.00:1
5th 0.82:1
Rev 3.66:1

the moggy ratios are
1st 3.628:1
2nd 2.172:1
3rd 1.412:1
4th 1.00:1

with the exception of 2nd ratio they are almost identical, the main difference is 5th that you use of the motorway for a more relaxed cruise

[cormorant]

Yes the 3.7 diff is about 12% different from the standard gearing but the 5 speed box gives you about 20% difference in top, I can't see the standard 1098 engine being able to use 5th gear very much at all.

[Jefftav]

For the mileages you talk about doing the 3.9 diff will work fine and be the easiest to install and run. If you can try to hear the diff in the car before you buy it. They rarely go wrong but you don't want to do the job twice.

The MMCB do sell a complete kit although I can't remember about the flywheel but if you were using a standard 1098 would you need another flywheel? Also you use the gearstick from the ford and mine came fitted to the gearbox but I have seen some who cut the ford one and weld on the minor stick, HIgear engineering offer this for £70ish (this is from my own investigations 2 yrs ago but can't see why it would change).

As PSL says if you really want to go the 5 speed route there are no modifications to the car that can't be changed back again. Place a wanted ad on here or in your local paper as they do crop up every so often.

[bmcecosse]

There needs to be a support for the front end of the input shaft to the gearbox - it's not long enough to reach into the oilite bush in the A series crank tail. So I believe a bushing with an oilite is fitted into the centre bore of the flywheel? Not something I have ever done - but that's my understanding of it. Hopefully someone will come along with some pics soon.

[Jefftav]

I remember now, the bush was fitted to the flywheel. Sorry I can't find the pic's though.

[bmcecosse]

How is it fitted in there Jeff - held in mechanically - or just 'trapped' by the crank tail and the input shaft ?

[Jefftav]

I hounestly couldn't say. As far as I remember it was a very tight fit in the flywheel so I don't think it relied on the crank or input shaft.

[stuart_k]

Thanks for the advice. Perhaps I'll leave well alone for now - until I get the hankering to spice up the engine anyway.

[Matt]

The spigot bearing is a interference fit into a bush, which is, in turn an interference fit in to the flywheel.

I agree a 3.9 diff would be your best bet.

My T9 5 speed conversion cost me £250 for the bellhousing (new but 2nd hand) and the associated metalwork. I had everything else I needed in stock except a propshaft which I made by shortening an escort one (prop - £40 UJs £20)

So I managed it for about £340ish in the end - but I would suggest its very uncommon to get hold of a complete working conversion that cheap, and there was a little of fabrication involved because I didnt have the "proper" kit

[jagnut66]

Hi, I am looking to do the 5 speed conversion myself, partially because I think my gearbox / clutch are heading west (well the old girl is 46 years old now ) and partially because I would like a smoother gearchange as she gets regular use.
Could you tell which Escort you sourced your propshaft from? (ie: a single piece one out of a 1600? mk1 or 2?)
Also how much length needs to be taken off to use it with a Ford type 9 gearbox.
Thanks alot. Mike.

[aupickup]

http://cgi.ebay.co.uk/MG-MGB-MGA-Morris ... 19b86c4680