I currently own a 92 F250 4x4 with a 460 and ZF5, nothing done to the engine but some intake and exhaust. It's got a D60 in the front and 456 gears front and rear. I want to retire my truck and get into a diesel. I really like the 80's to 91 trucks.
My question:
What kind of performance changes am I going to notice? Power, pulling, off road driving, highway cruising, driveablility and mileage? I would like to get a F350 4x4 with a standard trans. What are your opinions? And I would be looking at a diesel with a turbo, or installing one.
Thanks in advance.

 

if you go with something geared more moderately in the chunks, should notice better fuel economy. have a '90 250 nonturbo 4x4 with 4.10 gears and a 5 speed tranny. i have no trouble with low end pulling and average about 17-18 mpg on the road. all reports say the turbo makes for better fuel economy since it burns fuel more efficiently. i'll never know 'cause ain't got the bucks to add turbo. do have plans to add ram air and 3 1/2 inch exhaust. that's supposed to make more power also if you don't want to go turbo. think the diesel would have more than enough power unless you like to light the tires up. lots of mods can be done to improve the IDI engines AND there's no electronics to go out like with the powerstrokes. hope this hasn't muddied the water too much. love my
90 but the wife hates it. LOL

speedrdr

 

I am just getting into diesels myself. I am getting ready to get a 89 with a 7.3/c6.

I am not sure what gears it has, but it does have 35 inch tires. Driving it the other day, I noticed it's pretty doggy, with about the same get up and go as my f150 with a 351w 2bbl/c6. This was a little disappointing at first till I hauled a load of wood with it.

I had just hauled a similiar load on my f150, and you can really tell the difference. It really lets you know you have a load on it. What was strange with the diesel is there was not that much difference when it was loaded. It was it's old doggy self unloaded or loaded. This is pretty interesting, and I guess this is what torque is all about.

I have also read that a turbo and the diesel where pretty much made for each other. Unlike a gas motor with a turbo and all the complications, the diesel loves a turbo and gets better fuel mileage, more power, and is built well enough that a good power increase can be had without reliability suffering. I have ridden in a powerstroke, and it would set your eyeballs back in your head on every shift. I have heard the older diesels work just as well when a turbo is added to them.

So if you get the non-turbo diesel and compare it to your 460, you will definitely be disappointed. But if you add a turbo kit, or get one with a turbo, I think you will be happy with it, especially when you go to fuel up.

 

That 460 will pass anything but a gas station Biggest difference is fuel consumption. An IDI without a turbo will pull well, one with a turbo pulls very nicely. I may not be able to pull my 10k lb 5er as fast as a 460 with my 7.3 with ats turbo, But I can do it while getting 11-14 mpg. I've had 460's before, stick a good load on and pray for 3-4 mpg , take the load off....not a whole lot better.

Offroad is where diesels really shine, the steady low end torque will pull you out of spots where the big gasser will either bog down or spin the tires.

 

Franklin2 summed it up very well. When my 6.9 was still N/A, it could hold pace with just about anything, up to around 30 mph. After that, it would bog and run out of steam. Top speed on a 10% grade was about 45mph empty, exactly the same as my F150, but to get a load moving, the diesel will always have the edge (peak torque is at 1400rpm for the N/A)

With 3.08 gears, it cruised very nicely, even N/A with a C6 tranny. Running empty could sometimes produce 20mpg on the freeway.

But if your looking for something to match the 460, you may be dissapointed, even with a turbo, the diesel still may not be able to match the peak Hp, because the 460 can always rev up to make more peak power. The IDI on the other hand, is governed to ~3300rpm, which will give you 170,185 Hp for the 6.9 and 7.3 N/A, and over 250 Hp if turbocharged.

 

The real question is....how long are you going to keep the truck?

The cost of a rebuilt IDI and a 460 is big...almost twice as much!
A friend of mine is having his 460 rebuilt for his 76[?] F250...even with some extras,his cost is less than 1/2 of what I could get an IDI rebuilt for.

RLDSL, nailed it when he said the 460 will pass anything but a gas station.
Both are good engines....the IDI's are built for work and the long haul.

I love Diesels, but the're expensive!