transmission ratios and torque ratings?

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Wed, 23/05/2012 - 22:13
mjkirk
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Hi all, did I imagine it, or was there somewhere I can find out about merc gearboxes of all kinds with regard to ratios and torque ratings? Just returned to my 606 conversion and wanted to check out the choice of W124 manual boxes I have before fitting the wrong one. I've found myself short of a spare vehicle and wanted to at least try and make a bit of progress between work commitments rather than buying another temporary motor. Thanks in advance, Mick.

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Fri, 25/05/2012 - 00:33
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fcp
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Re: transmission ratios and torque ratings?

I'm jst starting out on a SuperTurbodiesel 606 conversion (603 IP, Holset Turbo, Myna pump for 350-400-ish smoke free BHP is the plan). I am using the 711.620 G32-5 gearbox from a Sprinter which is rated for 350Nm or so (but will hold much more aparently). 

Shifting is to be done using a modified Vario lever (the gearbox is a modern cable shift) which has (with a little fettling) just about the right shift pattern.  

Clutch plan is a conversion from Dual mass to single mass 228mm diameter (again made for sprinter) which needs to have the spindle bearing as part of the flywheel assembley due to the shorter input shaft on the trans. Not sure whether this will ultimately be enough.. the fallback is a Sachs M5 race pressure plate and clutch though that's a whole lot more work to do (flywheel needs to be seriously modified).

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Fri, 25/05/2012 - 21:53
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Pistonhead
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Re: transmission ratios and torque ratings?

Hello fcp,

This is a minefield of a question.  I think, it is for Mercedes Customer Services to answer.  Sorry, can not help in this instance. :-(

Cheers,

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Sat, 26/05/2012 - 18:51
#3
stig
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Re: transmission ratios and torque ratings?

 MB 711.117 - T=? - 1st=4.695, 2nd=2.401, 3rd=1.436, 4th=1, 5th=0.806..4.078
MB 711.116 - T=? - 1st=6.157, 2nd=3.148, 3rd=1.743, 4th=1.278, 5th=1, R=5.347 - Rem=No syncro on 1st
Getrag 717.439 - T=? - 1st=3.856, 2nd=2.182, 3rd=1.365, 4th=1, 5th=0.799, R=4.218
MB 722.3 Auto - T=? - 1st=3.871, 2nd=2.247, 3rd=1.436, 4th=1, R=5.586 - Rem=Here for comparision

Sprinter or E/C Class
MB 711.620 G32-5 - T=? - 1st=5.05, 2nd=2.6, 3rd=1.52, 4th=1, 5th=0.78, R=4.76 - Rem=Sprinter 2000+
NSG 370 Jeep - T=272, 1st=4.46, 2nd=2.61, 3rd=1.72, 4th=1.25, 5th=1, 6th=0.84, R=4.06 - Rem=Chrysler 4dr Jeep
NSG 370, 711.651 - T=272 - 1st5.014, 2nd=2.831, 3rd=1.789, 4th=1.256, 5th=1, 6th=0.828, R=4.569 Rem=Sprinter/ML CDI
NSG 400, 711.660 - T=? - 1st=5.453, 2nd=2.974, 3rd=1.873, 4th=1.332, 5th=1, 6th=0.777, R=4.946 Rem=Sprinter from 2009, has PTO
MB 711.670 - T=? - 1st=5.1, 2nd=2.78, 3rd=1.75, 4th=1.25, 5th=1, 6th=0.81, R=? - Rem=E/C Class CDI from 2008???

I copied this from another forum. 
Torque ratings I don't know except for the 'NSG' boxes, where 370 is the rating in NM.

Cheers Scott

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