Gearbox and back axle on a new project.

[polo2k]

Hi all, its been a fair old while since I have been on here but hopefully I will be able to get on here a fair bit more often now.

I have a 63 4 door in the garage to satisfy my sensible side, however I am going to build myself a bit of a toy.

I have already decided on an engine which will be 170hp at first, working its way to about 300hp if I think I can handle it once ive had a play at 170 ponies.

I think that the common consensus is that the Type 9 box is the one to go for. is there anything else I should consider before I start bidding on ebay? I want something that can handle the power reliably, has good parts availability and is relatively compact.
I want a box with a seperate bell housing to make the adaptation easier.

The other questions I have is about the back axle. As far as I have read the Mk2 escort mexico back axle is the one to go for as it is the right width for the minor and gets the bigger brakes. I have also seen a few limited slip diffs out there for this axle, I think one of these will be nessesary once I get giddy on the power.
I want to stick with a live rear axle for the moment to simplify the build of the project. Is the escort axle the only option? is there anything else I should look at?

How would a type 9 and Mk2 mexico axle be geared ? sensible or a little low?

sorry for all the questions but I want to get cracking on this project soon and will post progress as I go.

Many thanks

Ash

[ratrodmog]

The Mk2 Escort axle is a good choice but there is also the Toyota Celica axle to look at which I think is the right width (although I may be corrected). Also I'm not sure if the brakes are as good as the Escort? The gearing with the Type 9/Escort axle will be fine for normal use.

[polo2k]

would the the the GT4 back eld? or would it be something older?

What power limitations are there with the type 9 and mexico combo?

[polo2k]

I have just read that the replacement for the type 9 box (the MT75) is much easier to get hold of and better built while using most of the same mounting bits and pieces.

[jonathon]

The MT 75, (more trouble, ) as known, in the trade has an all in one casting of the box and bell housing, its also a much larger unit. No better than the type 9
We have faced similar issues with our racer re parts , which is why we have now limited the power (torque).
If going over 250bhp and over 200+ftlbs or torque then go for the T5 box and a narrowed Capri axle. Or add much better /stronger internals to the Escort axle (expensive).
It does depend on the sort of use you are going to give the transmission, if doing burnouts, and drag starts then you will need to upgrade ,if just fast road then you might get away with the std T9 and Escort components. What kills transmission is torque not peak bhp.
If going for big BHP then go for the V6 box which has longer gearing, or have a reconditioner fit the gear sets from the V6 into the T9 box. Diff ratios depend on what you are wanting, we use a 4.1 on the racer and a 3.54 on road versions. Running 15" wheels 195 50 fronts and 235/50 rears.

Hope this helps.

Ohh don't forget to upgrade the clutch and release bearing.

[plastic_orange]

An MGB axle is considered to be pretty robust - and easily available.

Pete

[Jon H]

In the Ford scene we're seeing a few MT75 swaps now since the ratios are better than Type 9, which has a whopping hole in the middle. The MT is bigger but the remote's very adjustable - almost put it where you want. If it were me I think I'd have a go just to be different!

You do have to pick your box though but, you get a nice concentric clutch slave cylinder too - the one all the Type-9 convertions use!!

Back axle - try finding a narrow Celica axle! Try finding any Celica axle....

An Atlas is more likely to handle bigger power but you have to, as Jonathon says, narrow it really to fit a Minor - think a Mk3's 54" -ish wide but as far as I know, the mounting brackets pick up on the Minor's - well they did on my van and the Mk1 Atlas I have is the same... Don't know if that applies to saloon based models - I don't know the distance between the springs (are they different to van?)

I will use my narrow Atlas on my van as it's the right width but I have a Mk1 Cortina axle on my saloon with 5 1/2js on the back (tucks in just right). On that I'd uprate it, which would cost about the same as narrowing and a pair of halfshafts on the Atlas. Swings and indeed roundabouts...

My traveller BTW has a narrowed 8" Ford with LSD!

Jon

[bmcecosse]

I suggest the Rover LT75 (later version is R380) 5 speed box is strong - compact and uses a bolt-on bell housing. Used in TR7s and easily fitted up with a bell housing to take the Rover V8 - as in TR8 conversions!

[polo2k]

Ive spoken to the local scrappies and the ford options are going to be the easiest to source and clutch wise will be easier.
I went to look at some boxes yesterday and all the MT75`s has integral bell housings. the only type 9 they had was missing its bell housing, it is a non cossie box so has the shorter ratios, I have decided to go for it as they will do it for £45 including the gear lever and a used friction plate for mocking up.
I will be picking this up later in the week.
for the release bearing I think I will use the VR one as it is concentric and hydraulic so I get freedom on the mountings. Another advantage of keeping the VW master cylinder is that I may be able to use the golf pedal box and master cylinders including the servo but before I buy anything I need to check the brake piston diameters as the minor will be on 2 pot calipers rather than the single sliding golf ones.
Once Ive got all the pieces together I will be able to get on with some fabrication

Hopefully the car will be here soon so I can start the tear down and strengthen and rebuild and strengthen some more.

[MartinB]

Escort 'English' axles can take a lot of abuse, I have also heard of them breaking with not much power so it really depends upon what you are doing with it (type of use)

A guy I competed against (hillclimb) a few years ago had a 2.4 Pinto (on carbs) powered Anglia and told me he had to change the axle tubes because he had sheared them off (this was with a very low diff ratio and quite large diameter wide slicks).

I have been using an Escort axle, admittedly with Quaife shafts & diff, with over 400 BHP but with smallish diameter slicks (although 10" wide) and the 3.54 ratio takes some of the torque off the axle tubes and shafts.

It really depends upon your tyre sizes (OD), gear ratios and therefore diff ratio. (Tall first in close ratio boxes needs lower diff ratio), and of course mainly what traction you will get.

For road use shouldn't be a problem.

[charlie_morris_minor]

i have a mk3 capri axle.. and the sits on the traveller springs mounts like the van with no modifications.

The only reason I decided not to use it was when i got the wheel on it was not sitting totally inside the body work. I used mondeo steel wheels.. 99p of ebay for 4! and they stick out by an inch or 2 at the most and i wanted to keep the car looking standard from the outside but a slight flare to the arch would have easily covered that.

[polo2k]

is there any particular place I might find a suitable axle? i was thinking tree bay but is there anywhere elsE?

[twincamman]

It might be worth looking at the Avenger/Sunbeam axle. It's good for 200bhp (or more if you weld bracing plates between the outside of the axle tubes and the diff housing to stop the tubes popping out). It's a bit wider than the Minor axle and has the Ford bolt pattern. It's also likely to be much cheaper than a Ford axle!

[charlie_morris_minor]

is there any particular place I might find a suitable axle? i was thinking tree bay but is there anywhere elsE?

scrap yards?