TH350 behind a 617 - PeachParts Mercedes-Benz Forum

MercedesRover · #1 08-20-2006, 07:39 AM

Hey all. If you don't know, I've got a '74 short wheel-base Land Rover with a Benz 616 bolted to the original transmission and transfer case for which I made an adapter. That project has been done for years now and for many many miles with no trouble. So on to another project.

I've just aquired a '67 long wheel-base Land Rover in which I am going to put a Benz 617 turbo in. As I want my wife to drive it and want something more reliable than the Rover transmission, I plan on installing a turbo-hydramatic 350 transmission and a Dana 18 transfer case behind it. It should make for a very reliable and tough drivetrain.

My question is if anyone has ever bolted this tranny, or any other automatic transmission other than a Benz transmission to these engines? Is there any reason anyone can think of why this can't be done?

Thanks in advance for any help or comments.

Jim
http://seriestrek.com

Hit Man X · #2 08-20-2006, 07:52 AM

It's going to be very slow with a TH350 behind it, it only has a first gear of around 2.5x:1...

nazrat · #3 08-20-2006, 08:02 AM

You might want to look for a 700R4. They have a much lower 1st gear and they have overdrive. They were used in manual (700R4) and electronic (4L60E) versions over the years, so you can pick one to suit your fancy. They were installed behind the Cummins 4BT in breadtrucks and the like, so they should be pleanty strong for the OM617.

If you do go with the 700R4, make two. I will seriously buy the second one from you.

-Tad

Hit Man X · #4 08-20-2006, 08:14 AM

Normally I wouldn't recommend the 700 as it's a piece of crap, but with the low output nature of the 617 (120hp/170tq) it's more than adequate.

PM me if you need a complete parts list for upgrades on it. I know more than 95% of the population on the 700/6E. Their biggest downfall aside from the monster RPM loss between 1st and 2nd gear (3.06:1 to ~1.56:1) is their valve body, it's very poor.

If you are planning to make an adapter anyway, I'd HIGHLY recommend a 200-4R unit. Ratios are far closer (2.74/1.63/1/0.67 I recall) and it's the same length. Should have the same 27T output shaft also. Also it's a fully lockup unit.

MercedesRover · #5 08-20-2006, 08:29 AM

The 700 had it's problems and aren't really though of as a reliable tranny. Not like the 350 anyway. I know a couple tranny shops and can ask them their thoughts on it. Perhaps if I had one built special....

The other problem is the adapter to link the 700 to a Dana 18 T-case (I have to use the Dana 18 as it a passenger-side drop both front and rear) is pretty long and makes the overall length of the tranny 28". Though this may not be a problem as it's a long wheel-base truck.

Don't know much about the 200-R4...What is it?

And as for the gearing, a four-speed would be nice but keep in mind this truck will have 4:70 or 4:56 gears in it and won't see speeds of more than 65-70 mph. Off-roading will be in low-range and a high first gear shouldn't be too much of a problem. This will be an expedition truck more than a rock-crawler anyway.

nazrat · #6 08-20-2006, 08:53 AM

http://www.novak-adapt.com/catalog/kit_107.htm

Novak's page on the 700R4:
http://www.novak-adapt.com/knowledge/th700r4.htm

-Tad

didget69 · #7 08-20-2006, 10:18 AM

Comparing both in stock form, the 200R4 is nowhere near as strong as the 700R4 - That being said, the 200R4 is physically smaller than the 700R4, and 200 series can be built stronger, but at what cost? 200R4's were usually found behind GM 305 V8's & V6 's -

700R4 valve bodies continue to be a weak-link, but most trans builders know how to correct these issues, within the limits of the existing design.

700R4's can be very reliable; I've got the original 700R4 in my 1991 S10 Chevy Blazer with 287K miles - Maintenance, maintenance, maintenance folks - and Yes, I have used it off-roading frequently in 4wd & for towing my trailer or dune buggy...

Good luck!
bnc

pmckechnie · #8 08-20-2006, 10:59 AM

If you want a 200R4 which is smaller, get one from a Grand National Buick. This Buick was the fastest production car built in the US for several years. If you ever get a chance to ride in one, take it. They are unbeleabible.

MercedesRover · #9 08-20-2006, 11:27 AM

Correct me if I'm wrong but I don't think the 200R4 comes in a 4x4 version. Looks like it's got a one-piece housing.

pmckechnie · #10 08-20-2006, 11:30 AM

Your right. Sorry

OMEGAMAN · #11 08-20-2006, 12:04 PM

With that adaptor we could start installing GM 5 speeds in our 123's.

MercedesRover · #12 08-20-2006, 01:40 PM

Funny you should mention that. I've got a standard shift bellhousing off an early 240D stick car (when the bellhousing was seperate from the tranny) and I was thinking about welding a plate to the back of it and bolting a Toyota H55F 5-speed to it for my short wheel-base truck. Never got around to it though.

Is there really a need for this adapter? I make and sell an adapter to bolt the Rover transmission to the back of a 616 and have sold a few but with the price of good aluminum most people won't go for it. The Rover crowd can be a little cheap! I get $700 for the adapter and a pilot bushing and have sold less than a dozen. An adapter to bolt a GM tranny to the back of a 616/617 would cost about the same. Do you think there's really a market?? It wouldn't be that hard to make but I'd hate to go through the trouble if I only sold three!

Here's the Rover adapter bolted to the back of the 616 flywheel plate.