Escort crown wheel

[David Kemp]

Some time back a Javelin owner put a Ford Escort crown wheel in his Javelin diff housing. This meant he could run 14" wheels without changing speedo calibration.
Does anyone know if the project was ever completed?
If so what Escort?
What wheels?
I think it was a Kiwi club member.

[george garside]

I have not come accross this one before and have doubts as to the interchangeability of escort & javelin parts for many reasons not least of which one will be made to metric measements & t'other to imperial. Assuming I am wrong and the conversion works it is presumably intended to provide a higher back axle ratio to compensate for a 14" wheel and so retain overall gearing of around 15mph per 1000rpm. the fact that the speedo would not need recalibrating would just be a sort of bonus.

Again if the 'conversion' is viable a better use may be to raise the averall gearing to reduce revs at todays cruising speeds. Has anybody calculated the rpm per 1000revs that would result.

george

[Leo Bolter]

When I saw the original post, with its reference to NZ, I immediately copied the text of the post and sent it off by e-mail to Vic Morrison, Neil Moore and others (they being the ultimate NZ Jowett gurus ) I am yet to get a response from Neil (his e-mails are read during business hours only), or the other folk, but Vic responded almost immediately. The text of that e-mail is quoted below.

Hi Leo, Never heard of this before and seriously doubt it could be done.
Cheers, Vic.
----- Original Message -----
From: Leo Bolter
To: Morrison Vic ; Moore Neil & Dennise ; Stanley Alan ; Bradford Sid
Sent: Saturday, June 23, 2012 12:42 PM
Subject: Escort crown wheel . . .

Gentlemen.

This has just appeared on the International Jowett Forum. Does anyone know details about this? And if so could they respond?

I know nufffing! (as Schultz would have said)

Leo.

But, while on the subject of alternative gearing, I do have a old printout of a spreadsheet that was compiled by NZ'er Ian Leighton (now a resident of Aussie) of various "other makers" differentials/axles/components to change the final ratios of Jupiters and Javelins. I'll dig this out and scan it if there's anyone interested. By the way, when Ian and Kate visited me earlier this month he revealed that he was presently working on his Jupiter "racer" to bring it alive and race-able after about 15(?) years in storage . . . great news!

[David Kemp]

Regards escort being metric, I don't know for sure but remember the first escorts are 40 years old! I doubt the UK car industry went metric over night especially American owned companies like Ford. Australian Fords of course were also mix & Match, with imperial motor components from local Ford , metric threads, but could also have imperial spanner sizes depending on age & source.Even window glass good differ for the doors depending on source.
This is from my experience as a wrecking yard hand in the late 1980's. Pain in rear when customer wanted side glass, we normally only had the one that was the Incorrect for their car. The reason for this diff change was to run cheaper more common 14" tyres without changing Javelin characteristics as well as Speedo.
Given this was sometime back it could be when I received The NZ & Australian club magazines, a longggggggg time ago. This may have been tried & failed, that is why my curiosity.

[Forumadmin]

Th Gallery has some pictures of Mike Allfrey's conversion of a modern diff to fit in a Jowett.

[Chris Cole]

I worked with Ford on gear design back in the 1970s and they were metric then as the Ford Cologne plant has design authority over gearbox design for Europe.

Even if the Escort crown wheel was imperial the liklyhood of it mating with the Javelin pinion would be very low indeed.
You might put an Escort crown wheel & pinon in a Javelin diff if you could adapt the bearings etc. though this seems a lot of work.

[jowettgeoff]

Some years ago, Mike Smailes and I each had a 4.1:1 crownwheel and pinion set made. Mike's went into his racing Jupiter (now owned by Ib Rasmussen) and mine was destined for my competition Javelin (BEG308). Both were assembled and set-up by a professional transmission engineer, and for some reason, the Javelin housing needed some light machining for the crownwheel to fit. To my eternal shame, I've yet to fit mine onto the car.

I can't remember the name of the company, but perhaps Mike might (01642553357 - before 9pm!).

G McA

[David Kemp]

Did Ian Leighton ever find the list of compatible diff's from other cars?