Hello,

I did a search but couldn't dig up any specifics, just some simple revving talk...

I'm wondering what the rpm is for an OM616 from an early '80's 240d is at, say, 65mph? Also, what about the red line rpm for the 616? All in all what is an acceptable rpm range for cruising down the highway?

I'm trying to make some gearing decisions for my Rover conversion project.

Thanks so much for any info!

IIRC the max rpm is about 4500.

A 240 will cruise at up to 90. They sound a little overworked above 72, imo, so I usually wanted to cruise at 72.

The gear in the 240 is 369 with a 175sr14 tire.

The range rover will be a bit more bulky and have more wind resistance so you might want to plan running a bit lower gear ratio and cruising at, say 65.

Tom W

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

In my sig is the specs for an 81 model year 240D from the Mercedes Technical Data manual, which covers all models made by Mercedes for that year. I'm assuming that the specs for my 83 240D is similar. I put a tach in my 240D with a 4 spd manual couple of months ago. From memory, at 65 mph the engine is doing about 3000 rpm. I am not driving the 240D today, but next time I do I'll verify the numbers.

edit here's the specs:

chassis 123.123 eng 616.913 2404 cc 21:1 5 main brngs, max 5400 rpm no load, 62 bhp/4000, 97 ft-lb/2400

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85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Thanks for the response, guys... it helps a lot.

Now onto making some gearing decisions so I can cruise comfortably at 65-70, with some 'ummffff' left over. The series rover is the epidemy of slowness - its like driving a brick down the highway! the SWB is small, but its still a heavy-ish and non-aerodynamic truck. Then I get to thinking how heavy my 240td wagon is being pushed by the 616.

Should be interesting!

Thanks again!

Also, do you have the same specs handy for a 617 turbo? I may be starting another conversion project using the 5 cyl and will have to know rev range/redline and torque output. I recall the 617.912 putting out ~125hp. At what rpm(s) does it have max hp/ft-lb?

Thanks!

617.912 is NA, not turbo. The 81 tech data manual, under general engine data, list the

617.912 at 80 hp/4000 up to sept 79, 88 hp/4400 after sept 79. Torque 172 NM/2400

for the 617.952 turbo diesel engine 125 hp/4350 , Torque 250 NM/2400

For later than 81 model year turbo diesel 617.xxx I believe hp and torque have gone up but I do not have the book.

__________________
85 300D turbo pristine w 157k when purchased 161K now
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Thanks Funola,

Ah, it is the .952 I was referring to... its been a while since I've done my homework. The RPM data will prove to be useful!

Thanks - I'm sure more to come! I'm excited to get started on this project again...