Dart562

I have a D350 Custom with a crew cab, a 8 ft bed, 2wd and a 5.9 Magnum from a 1994 Van. I was thinking about doing a engine swap because i am having problems passing smog and i really hate the MPG especially with the gas prices here in Cali. So i was wondering what engine would be a good candidate to take its place. It has to have good power, reliabiltity, and descent MPG at least 15....Or is there a way to get my 5.9 magnum from 8 mpg to at least 15...i am limited on money but will work with anything that works....The 5.9 is a amazing engine but is just to thirsty for my cost right now

Chryco Psycho

I guess my question is what gearing do you have , how many RPM are you turning , what do you use this for mostly , hauling or highway ? I assume it will have a Dana rear diff , Maybe 4.10 rear , I would be looking more at a 518 trans with OD , the Magnum should get decent mileage if tuned well & the rpm is kept down . It will take a long time to save $2-3000 in extra fuel costs too .

Mr.4spd

Advancing the ignition will help, but you'd have to lock out the computer or it's gonna fight you.

440roadrunner

What year is the D350?

Frankly, I don't know many older D350's that get anywhere near 15 mpg. 12, MAYBE

What are you using for carburetion/ injection?

I'm not familiar with smog laws "there" but in many states it turns into a huge sticky tarball really quickly.

For one thing, there may be fuel tank vent systems (older bodies) that cannot be easily integrated with a newer injected engine

On the other hand, may states have laws stating that IF a newer engine is installed, then the car/ truck then must meet the smog standards relating to the newer engine. Again, sticky, because there may be systems related to the newer engine that cannot be easily integrated into the older body.

Off hand, I'd say that you can't "meet smog" with a 94 5.9, something else is wrong besides the choice of the engine itself

PK1

What is the curb weight of that truck? And what exactly are you using for a carb or fuel injection?

78D200

Rear axle will be a D60 and like someone said before, probably 4.10 gears. What do you have for a tranny? Fuel delivery system is a need to know before we can assist. What is the truck used for mostly?

I'd be willing to bet that truck is weighing in around 6500 lbs. if not more. Crew cab, long bed, probably a duelly to boot.