looked at a 758 cab and chassis, no engine or tranny. truck had a dripper in it from factory and thought it could have had an automatic in it, is that possible. what would be the biggest cummins that would fit under the hood. i have a 400 bc that i have had and thought that i could put the truck back together and it would make a nice six wheeler with dump bed.
any ideas gg2

A local township had 758 single axle plow trucks with Detroits(6V71's I think), with Allison autos in them. I know that turbocharged 855 Cummins came in 758's, so no reason a 400 wouldnt fit.

must be a real tight fit with the dog house. hope the deal goes thru, cab is in real nice shape, hood and front clip are nice too, chrome cowl. frame is like new but cab was pulled and all electric and air lines were cut. front axle is still under it but rear is gone. fuel and bat. box is also on frame. thanks
gg2

A turbocharged Cummins will fit in a 758. I do not think a 400 with the aftercooler will fit in a 758. The biggest Cummins offered in a 758 I think was a 290 no aftercooler. Joe D.

thats what i was wondering.
gg2

Hmm, ya I forgot about the aftercooler. That may be a problem

is that with engine on slant or straight

OK Stan, What's an "after cooler" ? Is it analogous to an Inter Cooler on a turbo charged car?? Meaning after the compression stage of intake and before induction into the cylinder or something else?

Emery

Don,
Think the only way the 855"s will fit in the 758's is to slanted- for clearance issues.

75 N761TL 86937
76 N758LL 90502 parts
77 N761LL 91249

Clay

inter-cooler = between turbo and intake manifold.
after-cooler = "after " the turbo charger, same as above.
CAC or "chassis mounted charge air cooler" = mounted on the frame in front of the radiator.

All three perform the same task, to cool the compressed air from the turbo, before it gets to the intake of the engine.

As for an after-cooled 855 in a 758, nope, not enough room. That's why the 359/759 was developed. The high cab provided clearance for larger hp engines with coolers.

In later years (early to mid '80's) there was a cooler developed to use on the Big Cam 3 & 4 that might work. It is a great deal lower and smaller at the rear of the engine. Unfortunately using a low flow cooling Big Cam 3 or 4 would require the correct radiator to match the cooling system. It could be done though.

Emery
Another part of the answer Stan left out was that Cummins first used a less efficient water cooled unit between the turbo and the intake manifold, which was mounted on the top of the intake manifold, before they developed the "air to air" (CAC) unit in front of the radiator. The height of this unit (which Joe mentioned) and being on top of the intake is what is causing the clearence problems in the 358 design and as Stan said part of the reason for the 359 design.
Brocky

The intercooler/aftercooler, whatever you what to call it, is actually the intake manifold and cooler element all in one. It was used on all the 855 series Small and Big Cam 1 - 4 engines up until they changed the name to N14 (855 cubic is 14 liters) and eliminated it in favor of the CAC. This intercooler changed the NTC 335 to an NTC 350 with no other changes. Most every engine above 290 hp has a cooler with the exception of the old NTC 335 which tended to run hot in a hard pull. The addition of a intercooler solved this problem and created one of Cummins best ever engines, the 350.

don, in addition to what everyone has said you will need a different intake, crossover, and exhaust manifold. Everything is moved forward because only 2 cyls are under the hood. The 3 pieces I mentioned are the same/similar to a short hood louisville ford with a cummins. Also if you want a jake brake install it before you put the engine in the truck. In a nut shell theres just too much stuff all trying to be in the same place, or better known as 10 lbs of you know what in a 5 lbs bag.

As we are on the 758 subject will a backdrop manifold fit in a 758 without much trouble. Joe D.

don, in another case. why not wait for a small cam cummins of some sort to come along to put in the 758 and save the big cam for a rainy day? you never know, you might need the 400 for your 761 if you had a bad piece of luck and it needed a total rebuild. doesnt hurt to have extra parts, motors, ect. but stan is right, anything can be done. glen has a turbo charged 358. just had to sacrafice the floor.

richie

This reminds me of someone I knew who needed an extra set of rod and main bearings and crank and block for a continental.

was just thinkin, have a spare 400 0n the floor now, and a 350 bc coming in. plan on changing the pump and injectors on the 761. bump it up to 450-500 hp.
gg2