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A post from Arwyn some time ago has had me pondering for a while, and considering I spend quite a lot of time bimbling around in 4th at 60mph, the thought of a 20% reduction in rpm is quite appealling. In real terms it would reduce revs from 3100 to 2600 and if I did want to boot it, 70mph could be had at 3000 revs rather than 3650 (based on a 5th gear ratio of 0.82)

On my recent hoilday (did 1000+ miles in the week) at times I was averaging 38mpg so a reduction in revs should stick her into the low 40s.

Anyone know anywhere/anyone that would be able to carry out a 5spd conversion? Rather avoid main stealers as their prices are ludicrous.

Although I probably have the ability to carry out the swap myself, I lack the space - not something I could do on my 4m front drive, especially as I'm not able to leave anything out overnight.

The other option would be changing the rear diff ratio. Anyone done this before?

As I said before, my driving style is pretty relaxed - not bothered by mad acceleration or breaking the national speed limit. I have bikes for that.


"Y mae dafad ddu ym mhob praidd"
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Not sure you can readily change the rear diff ratio, not too sure theres an alternative.

I've sent you an PM as I've got a pretty comprehensive how to guide which I can send you.

Arwyn

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Thanks Arwyn,

Just need to find a tame mechanic to do the conversion smile


"Y mae dafad ddu ym mhob praidd"
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Probably easier to go for a change to a ford five speed gear box.


.+8 Now gone for a 1800 4/4. Duratec in bright yellow.
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Originally Posted by TBM
Thanks Arwyn,

Just need to find a tame mechanic to do the conversion smile




Have you considered us?


Simon @ Sifab.co.uk

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Originally Posted by SimonH
Originally Posted by TBM
Thanks Arwyn,

Just need to find a tame mechanic to do the conversion smile




Have you considered us?


I hadn't but have now smile

I know Rugby well, my other halfs family live there, and she works on Swift Valley. I'll drop you an email.


"Y mae dafad ddu ym mhob praidd"
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Don't rule out the Mazda MX5 gearbox. Much better ratios than the Ford boxes and still in keeping with Morgan as the current 4/4's use this box.


Bob

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Originally Posted by IvorMog
Don't rule out the Mazda MX5 gearbox. Much better ratios than the Ford boxes and still in keeping with Morgan as the current 4/4's use this box.


Not sure how easy it would be to fit to a Ford Crossflow? The type 9 5spd conversion is quite commonplace (lots of lotus/westfields/locosts have done this) and as far as I've read doesn't require 'too much' fettling.

Have you got any references to a Mazda/Crossflow union? Would be useful to see.


"Y mae dafad ddu ym mhob praidd"
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You are the happy owner of a car with the right gear ratios. Don't change. Modern cars have too hight gear ratios due to low emissions restriction, inducing lower accelerations. My 2005 PLUS 4 has quite the same 5th ratio than the last Porsche which wins Le Mans... but not with the same power. The theoretical maximun speed of my PLUS 4 with the Ford gearbox is 160 mph at maximun rev!!!

Last edited by CBY; 08/09/20 09:13 AM.

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Originally Posted by CBY
You are the happy owner of a car with the right gear ratios. Don't change. Modern cars have too hight gear ratios due to low emissions restriction, inducing lower accelerations. My 2005 PLUS 4 has quite the same 5th ratio than the last Porsche which wins Le Mans... but not with the same power. The theoretical maximun speed of my PLUS 4 with the Ford gearbox is 160 mph at maximun rev!!!


The Type 9 has identical gear ratios as the standard 4spd box for gears 1 to 4 (3.65:1, 1.97:1, 1.37:1 and 1:1). The additional 5 gear gives a ratio of 0.82:1

Thankfully, there's more than enough power to handle the lower ratio. Not looking to increase top speed, but will be less strain to bimble along at 60mph at 2600rpm, rather than 3100rpm.


"Y mae dafad ddu ym mhob praidd"
1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10
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