Long time no see. I have a 240D motor from an 83 with an adapter plate to a chevy t5 trans. What rpm are these the happiest at for 70mph cruising? My project vehicle will weigh about 3200lb, possibly a little less. I have scales, so I'll check when I get that far.

I'd rather have the one out of a 300d, but prices are a bit much around here in Iowa. Are the later ones from say, 1995 computer controlled? There is one of those near me cheap. But I do not want to deal with a computer.

Whatever i buy, I'll part the rest of it out here.

What vehicle are you putting the 240d engine into?

Stock 240D weighs around 3200lbs as well and at 70mph it cruises at around 3600rpm. Thats with a stock 3.69 ratio automatic or 4 speed manual

It needs high rpm to climb hills without downshifting.

Because you have a 5 speed manual you could use 4th as climbing gear and 5th as cruising on the flat.

Your transmission ratios are 1.00 4th and 0.63 5th?

You either need something like 3.46 or 3.69 axle ratio or to have 5th as cruising/climbing gear you need something like 5.50 ratio

I own a 95 E300D and it’s not computer control 97 and newer are computer control

I would want to know which engine he will be using before commenting on the rear end ratio. The usual Germanic strategy is to provide a taller gear with the bigger engines to reduce engine speed and noise and offset additional fuel usage.

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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.

Thank you for the replies!
The car I want to put it into is a '36 Chevy. I'll be installing either a ford 8" or 9" rear axle. I have both, I need to start measuring. The 8" is lighter and plenty strong enough but has limited ratios. Most used axle gear ratios in the 4s or 5s for the 9" can be had for $250 from racers. From what I remember, these motors like to rev to move.

christuna, I like the idea of using 4th for hills and 5th on the flats. So I'd get the rear gear and tire combo that lands me at 3600 in 4th. I don't know the 5th gear ratio, I'll have to check around. I bought the trans used.

Benzguy300, thank you for the input. The option here is that I might be able to score a larger engine with a turbo and that would be way more fun to drive than the 240 na motor.
I might just drop the 240 motor in and keep an eye out for another 300 series car. I'd rather be driving and have to change a rear gear than wait for another engine and stare at the car.
I'll know more on saturday.

I have a ford 9" in my CE and wish I had gone with a lighter rear end....may be that 8". I am running 3.0 rear end gears and wish I had 3.50 or so. I have the mb od stick with the 18% od. My tires are around 28" diameter. with the 9" the rear is fairly bouncy. I am running the stock rear springs with overloads and a mustang 2 based front end. My thread here is "1939 Studebaker coupe express."

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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.

DV:

With all respect to the merits, or demerits (depending on one's point of view) of the OM616, an overall top gear ratio of ~ 3.6-3.7 will be required for 70HP.
The T-5 box was made in a wide variety of gearsets with 1st gear ratios from 4.03 to 2.95, and 5th gear ratios from .86 to .63. Late 1980s to 1993 4-cyl S-10s had T-5s with the 4.03/.86 combination. With a 4.1:1 rear, 5th would be usable, 3.9:1 a bit tall but OK with a tail wind.

Looks like my last post never made it. I ended up buying a 53 chevy 210. I'm just now sourcing a rear axle. I haven't had a chance to look at the tranny to see what it has, I was told it came from an 88 s-10, but I'll have to check on a casting number or look fro a tag I guess to get the ratios.

Well, the trans has the 4.03 1st and the .86 od. I got a rear axle with 4.11 r/p and I'm welding the new spring perches on tonight. The trans needs to have the throw out bearing sleeve cut down, and the bolt holes reamed a few thousandths for the bolts to fit. I also need to source the oil filter relocation kit.

How many people just relocate the factory one and anyone use just the single stage aftermarket ones?