I think I have enough power to run either one, but I already have a 2.88:1 speedo. I'm running 1.0 BaR of boost, so pulls in high gear are still pretty good. Alda is CCW to the stop and very light smoke at WOT. I may add some shims in the near future...Robert

DDH,

I routinly net 24-25 mph with my 617.950 with a best ever of 27 mpg on a long trip. I would like to get 30 mpg if at all possible. Based on your real-world experience, how much more, or less, fuel ecomonly did you gain with the swap to a 2.88:1 differential???...Robert

Still haven't found a 2.88:1 diff yet and I am still a bit unclear on what will be required to swap it into the 116 chassis.

Input???....Robert

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Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

My 83 SD someone put the 2.47 . Who cares about 0-60 mph. I love getting,32 to 37 mpg. On Multifuels,bio,Veggie,Used atf,motor oils,Citronella,Baby Oil,winter wmo diesel mix.(noone can smell my car ) laugh.On 100% diesel fuel,she's a speed demon.

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1999 w140, quit voting to old, and to old to fight, a god damned veteran

I am still looking for a 2.47:1 differential. Right now I am turning 3,000 rpm @ 67 mph. The 3.47:1 axle swap would reduce my cruise rpm by approximately 550 rpm.

Any good list of donor cars by year, model and engine that I can start looking for????

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

1981 - 1985 w126 gassers. 380SE, 500SEL.

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1983 123.133 California
- GreaseCar Veg System

Thanks!!!!

2.88:1 or 2.47:1???? Or, were both ratios available in these cars????

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

2:88 was only a one year thing in the 85 300D and 300SD.

2:47 in the W126 gassers up to 85.

In 86 thru 91 on the W126 the design for the rear Diff mount was changed.

Up to 85 they bolt right in. might have to change the Diff flange. the W123 uses a smaller one than the W126.

Not sure if your W116 is like the W126 or W123 flange.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Thanks Charlie!!

I haven't done much parts swapping outside the engine bay, so this is great information!!!!!!

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

I have 2 2:47 I pulled last year, one for the 84SD and the other for the 85 300D. I`ll be more of an expert in the install dept when I get around to it.

If you have to change the flange, there is a friction preload to determine before pulling it apart. here is a thread where I finally got it into my head on how to do it.

www.peachparts.com/shopforum/showthread.php?t=233540

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

Charlie,

Can you give me the full specs on your 2.47:1 donor car???

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

1985 380SE 201000 miles. and the second was a 83 SEL 133000 miles.

Charlie

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there were three HP ratings on the OM616...

1) Not much power
2) Even less power
3) Not nearly enough power!! 240D w/auto

Anyone that thinks a 240D is slow drives too fast.

80 240D Naturally Exasperated, 4-Spd 388k DD 150mph spedo 3:58 Diff

We are advised to NOT judge ALL Muslims by the actions of a few lunatics, but we are encouraged to judge ALL gun owners by the actions of a few lunatics. Funny how that works

I just refueled this weekend and logged 554 miles on 21 gallons, averaging 26.3 mpg and this was with more than a few +100 mph blasts and sustained cruise speeds of 70-80 mph, so I am confident the car would get better economy with less throttle opening. Still, that's respectable for a 617.950 as my memory serves.

Definitely looking into a 2.47:1 axle as I think the 550 rpm reduction at cruise could quite possibly push this into the 35 mpg range...Robert

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership

There is a benefit going from the 3.07 to the 2.88............about 1.5 mpg or so.

Those that have switched to the 2.47 couldn't document any fuel economy improvement over the 2.88. Apparently, the reduced engine friction at the lower rpm isn't significant when compared to the horsepower requirements necessary to push the vehicle through the air.

Hmmmm.....

Could be....I have noticed that a 500 rpm reduction in my wife's Dodge Magnum is good for about 10mpg. It has a 5 speed automatic and she recently drove it to So Cal in 4th and didn't notice it, with cruise on all the way. Coming back in 5th, she pulled another 10 mpg...Robert

__________________
Did you just pass my 740 at 200 kmh in a 300SD?????

1978 300SD 'Phil' - 1,315,853 Miles And Counting - 1, 317,885 as of 12/27/2012 - 1,333,000 as of 05/10/2013, 1,337,850 as of July 15, 2013, 1,339,000 as of August 13, 2013



100,000 miles since June 2005 Overhaul - Sold January 25th, 2014 After 1,344,246 Miles & 20 Years of Ownership