M42 Gearbox ratios same as M40 gearbox ratios?

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Ch4ni
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Tue Feb 05, 2013 10:43 am

Hi
Could someone please adivse if the M42 (Getag 240) gearbox is a close ratio (i.e. a sport gearbox) or does it have the same ratios as the standard M40 gearbox?

I am looking for a sport gearbox for an M40 engine does one exist?
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IlovM42
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Tue Feb 05, 2013 12:31 pm

talking about E30 gearboxes they are all the same ratio for M40 and M42, but gearboxes from E36 are what you called "close ratio" as they have 5th gear with a 1:1 ratio (E30 ones have 1:1 ratio in 4th and 5th overdrive)

so an e36 gearbox on your M40 or M42 powerded E30 is a good improvement, I'm actually planning on fitting an E36 gearbox with a 3.45 diff, it will be more or less like having the stock gearbox with a 4,27 diff, but with longer 1st gear :wink:
rix313
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Tue Feb 05, 2013 9:20 pm

There is a slight difference but its very small IIRC.
eko
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Tue Feb 05, 2013 11:30 pm

I have an E36 M44 gearbox available for anyone looking :D
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senna
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Tue Feb 05, 2013 11:52 pm

I replaced an E30 318is gearbox with an E36 box.
I found that the car was more refined on the motorway however overtaking (over 80MPH) required a change from 5th to 4th.
Around town there was not much difference.
Slight gains in economy.
Slight loss in in-gear flexibility.

It was running a 4.1 LSD

If anyone wants the old E30 M42 box (it jumps out of 4th occasionally when changing down from 5th at 80 mph)
£5 Collection Only SE24 London. (p.m please)
I have no use for it except for an autopsy



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IlovM42
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Wed Feb 06, 2013 7:57 am

rix313 wrote:There is a slight difference but its very small IIRC.
slight difference? :eek: no so light

if you put an E36 gearbox keeping the same diff ratio it's like using only the 4 first speed of the E36 gearbox...

one of the best setup is M40/2/4 with E36 gearbox and 3,45 it's what i'm about to do on my 318is e30 and it's the setup on most 318is/TI E36 :twisted:
eko
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Wed Feb 06, 2013 8:42 am

I can also supply a 3.38 diff to go with the m44 box if needed :-)
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