Morris Ital rear axles

[goodwoodweirdo]

I understand early 7’s used Morris marina / Ital rear axles (3.75” PCD), can anyone tell me from which model or the ratio ?
I’ve also read the Ital Van uses a late MGB axles (4.5” PCD)…..but thats something else....

Thanks in advance

Matt

Edited by goodwoodweirdo on Monday 4th October 15:11

[Noger]

Either Standard Marina or Ital and their light commercial variants. Or Triumph Spitfire or Dolomite (but not the Dolly Sprint). Minefield !

The heavy commercial had a different PCD as you say.

Ratios vary a lot. From 3.27 (which is what I have in the Gixxerham, it is from a Triumph GT6 with overdrive IIRC) through 3.63 (4 speed), 3.89 (5 speed) to 4.11 (which is what the grads use).

Think they go higher still, the light vans had 4.55. Nippy, but runs out of puff early !!

Rimmer Bros have a lot of info if you need.

[goodwoodweirdo]

Thanks Noger,

Just the information I was looking for ....

Cheers
Matt

Edited by goodwoodweirdo on Tuesday 5th October 12:34

[EFA]

You sure Noger? I know you own a Herald (even if its not called that any more:-0)

The GT6/Spitfire/Herald/Vitesse uses a transverse spring and fully independent rear setup. See http://www.kdtriumph.com/martini-gt6-rs/uploaded_i...


Are the actual diffs the same as the Marina item?

I thought Marina/Ital came from Moggy Minor parts heritage, and GT6/Spitfire/Herald/Vitesse all from Herald a la Standard Truimph.

[Eric Mc]

That was my understanding too.

My 1996 Seven Classic SE has an Ital set up.

[wobblyweb]

My Seven has the Standard 10 axle with a an LSD. The Marina diff is based on the Standard 10 diff and has "Stanpart"cast in the same as the Standard 10.
I use the LSD and swap between Marina housings and the Standard 10 to get different ratios. The Marinia has wider bearings and thicker halfshafts.
They are very similar but not the same. Standard 10 later became Herald Spitfire etc all the same.

Rae

[Noger]

Ah no, have got it the other way round, the non-overdrive GT6 is 3.27.

That is the CWP I got from Rimmer Bros. And it fits the Caterham diff (which I think were all 1600 Itals that Caterham used - although you did tell me bits were from an Ital Van on "ours" EFA).

There are other cars with 3.27, like auto Dolomite 1850s, but they don't have spares as readily available !

That was just ratios I was talking about. Whether you can take a MkIV spitfire diff and stick it straight into an LA Caterham.....I have no idea. But the diffs are similar enough for the CWPs to be compatible.

It is the TR4/5s and Dolly Sprints that use the other type. 3.45 ratio one.

Edited by Noger on Tuesday 5th October 15:37

[BDA]

I can confirm what noger said, CW&P and diff internals are interchangeable across Itals, non sprint dollies, spits and GT 6's. There is minor differences due to bearing sizes, this is due to age brakes and not models so sometimes it's a bit hit and miss to get the right bearings for a caterham as you don't know the age of the axle. Diff casings externally can be different dependant on source. I found rimmers can be a bit difficult if you mention caterhams, Jigsaw always very good and offer uprated CW&P's

Wobbly web.
Are you using an Ital diff in a standard ten axle? I am aware that the diff fits but how do you get around the issue with half shafts, IE if you use Ital shafts they are too long


Chris

Edited by BDA on Thursday 7th October 19:06

Edited by BDA on Saturday 9th October 15:01

[wobblyweb]

HI Chris
I use Standard halfshafts as you say the Marina are longer and the splines are bigger. I mix and match the internals. The LSD fits any housing and I use the crown wheel from a Marina and bolt it to the LSD and into the housing with the pinnion fitted. Marinas have wider bearings but its OK to use the narrow Standard bearings in the wider Marina housing.
Its all worked well enough for me for years.
My Lotus Seven has a tuned Twin Cam in and although i am not too hard on the axle it has survived well. Ive snapped 1 halfshaft and sheared the woodruff key once. I guess the LSD helps.

Rae

[BDA]

Rae,
Just to confirm, your LSD has standard ten side gears?
The reason I am inquiring is I am possibly looking at fitting an Ital/marina diff in a standard ten axle, which then causes me the issue that the diff side gears have the larger spline than the standard ten axle. Although part of the reason to fit the Ital diff is to have the benefit of the larger dia shafts (but these will need to be shortened, bespoke manufactured)

Cheers
Chris

[wobblyweb]

Hi Chris,
sorry not sure what you mean by side gears. The Marina diff will fit straight into the Standard Ten axle, if you are planning to have marina halfshafts cut down they would fit the diff but i am not sure what effect that would have on the outboard side. Thicker halfshafts would not fit the outboard seals for instance. I have 3 sets of ratios and use the Marina or Standard housing with the pinnion fitted then bolt the big gear onto my LSD with the small splines for the Standard halfshafts.
I have had similar thoughts to you about cutting down the Mariana shafts,also maybe widening the standard axle but then might as well fit a Marina. Have you thought about having stronger Standard shafts made?
Rae

www.lotus-seven.co.uk

[BDA]

Rae,
By side gears I mean the sun wheels, IE the splined female gears in the sides of the diff that the half shafts fit into. Which is now obvious they must be standard ten size as you are using standard shafts.
As for getting shafts made up, it is prohibitively expensive unless you can get a good few people on board and get a batch made up. I was going to have a look at shortening some marina shafts but haven't got around to looking at the feasability yet. as you say if you look at widening the standard axle you may as well just fit a marina/ital.

Cheers
Chris