Cummins guys...

[Smokin 440]

I have a 1989 3.9L Cummins 4cyl, it is just like the 5.9 just 2 less cylinders, but I think the same size turbo. It is rated 105hp @ 2500rpm, by turning the fuel up i can get 160 or so hp, but i don't recall the torque... The plans are to intercool it and inject propane to get hopefully over what the LPG 3.9 produces for power which is 195hp and 420ft/lb...

I have big plans for this motor so I'm wondering what the 5.9 12v Cummins around the late 80's early 90's had the potential for and what can all be done to this motor...

Thanks

[stalefish_132]

i'm not to familier with the 3.9 but i'd tap a pyro into the manifold and intercool the beast before turning up the pump, i'm sure some cummins fans will chime in here pretty quick...

[milehigh450r]

What kind of vehicle are you putting the motor in? Sounds like a fun project.

[Smokin 440]

Originally posted by milehigh450r
What kind of vehicle are you putting the motor in? Sounds like a fun project.

Well the motor originally came out of a 1989 Winnebago Delivery Vehicle, it loaded it was over 12,000 lbs. Right now it's just going into a 1989 Ford F-150 reg cab long bed with a 6" lift and 33" tires. The truck was a parts truck so the engine and the front panels are missing making the mounting pretty easy (I hope). The tranny and transfer case were Ford units in the Winnebago, the Winnebago was front wheel drive only though (pretty unique) but the tranny wasn't too different, just the ratios and the shifter is offset 10". The 4spd and t case from the F-150 are already bolted on. The F-150 for some stupid reason had 3.05 gears, but that's a good thing; with the 33" tires the gearing should be decent (4th gear should pull 80mph @ 2500rpms and about 96 mph 3000rpms)

Eventually it will end up in a reg cab short bed; My brother has and 86 f-150 that it might end up in... I hope to get a 5spd overdrive tranny and use 3.50 gears, but I want to see hope everything works in the parts truck before I go that far...

[CannondaleRider]

It would take a lot of coin to get the 4BT up to a decent HP level.

You can always Twin Turbo it........but $$$$$$$

[Smokin 440]

Update- The motor has been in for a few days and finally today everything was done just before dark (the truck has no lights)
The test drive shocked me, the truck hauls @$$. As soon as a got out of the driveway I punched it in 2nd and the tires went up in smoke, and the acceleration after that was pretty nuts. There is a hill by my house which most cars can't do 60 by the top(a buddies Eclipse Gsx can barely do it, my old car could, and a stage 2 srt-4 almost did 65) I was at least half way thorugh 4th gear by then which should be right with those cars.

After the ride it was dark, some changes were made... The clutch needed to be bled better, the shifter broke, and it needed a few more rpms to keep the motor from falling out of boost between shifts so we upped from 2700rpm to 3000 or so. Tommorrow is another day, and I'll see what the gps tells me for speeds. I have pics of some of the project but my P shop isn't working so I can't resize them... I'll try to post them sometime.

[Smokin 440]

Got some of the pics

The motor ready to go in, it's pretty dirty, it's 18 yers old and sat the past 9

[Smokin 440]

The truck ready for the motor

[Smokin 440]

In the first time, the truck motor motor mount had the be cut out, the original mounts off the motor had to go, and the oil pan needed to be changed; luckily the sump could be rotated rearward, and our tractor mechanic had a junk motor with the right oil pickup...

[Smokin 440]

Going in the second time with the revisions made, I was suprised the cherry picker lifter the whole motor, tranny, and t-case assembled... The first time we used our small loader tractor to get it in... One of my friends chose to stay clean in the backround...

[LTZ400rider]

thats pretty cool, is it carbed or FI. wat kind of exhaust are you running? id put some stacks on there

[Mxjunkie]

Very cool idea, I wanted to put a diesel motor in a s10 because back in the mid 80's chevy put a Isuzu diesel motor but it was a tiny little thing, I was thinking a cummins or a duramax but they are to long :(

[forty]

Originally posted by Mxjunkie
Very cool idea, I wanted to put a diesel motor in a s10 because back in the mid 80's chevy put a Isuzu diesel motor but it was a tiny little thing, I was thinking a cummins or a duramax but they are to long :(

We have a 95 S10 with a 83-84ish Datsun diesel in it. We had to make a driveshaft, motor mounts, cut a new hole for the shifter, and some other small stuff. Gets 40mpg.

[Mxjunkie]

Originally posted by forty
We have a 95 S10 with a 83-84ish Datsun diesel in it. We had to make a driveshaft, motor mounts, cut a new hole for the shifter, and some other small stuff. Gets 40mpg.

What all had to happen with your firewall? I know we had to remove the ac, heater etc to fit the v8 in the ones we've built, I've just allway's had this crazy idea to put a diesel in one and work it just a tad, who wouldnt like a little truck blowing black smoke :p :devious:

[Smokin 440]

Originally posted by LTZ400rider
thats pretty cool, is it carbed or FI. wat kind of exhaust are you running? id put some stacks on there

It is part of the original exhaust from the delivery truck, It's 3" and mandrel bent, except we had to do a cut and bend to get the bend a little tighter, then there is another peice of 3" welded on to get the exhaust below the frame. It's basically an open downpipe, A full 4" exhaust will be in order on the final truck.

[nosliw]

Originally posted by LTZ400rider
thats pretty cool, is it carbed or FI.


pretty sure that particular deezil is FI. :blah:

[forty]

Originally posted by Mxjunkie
What all had to happen with your firewall? I know we had to remove the ac, heater etc to fit the v8 in the ones we've built, I've just allway's had this crazy idea to put a diesel in one and work it just a tad, who wouldnt like a little truck blowing black smoke :p :devious:


The Datsun 2.2 is a longer than the GM 2.2N but we didn't have to do anything. The head is about an inch from the fire wall and we had to modify the radiator shroud a bit and that it. We cut out the cat and run the stock exhaust.