78 F600 4X4 389 XD engine :
current transmission is a Clark 285 V, thinking about an overdrive, is a 285 VO the best all round option ? if so where can I find one ? if not what would other options be ?

389 XD : I would like to increase torque output a reasonable (25 % ? ) this would sort of go hand in hand with the overdrive gearing , is the 389 a decent base for the increase or perhaps the stock heads & intake are already maxed out ? this motor has been with this truck since it's birth so I would rather not put a different motor in it , do the cam grinders make a cam suited for truck usage ? governor currently limits to 3700 rpm ok flame away !! thanks

 

What kind of service will the truck be doing ?

Some discussions here about that truck:
https://www.ford-trucks.com/forums/9...x4-1978-a.html
https://www.ford-trucks.com/forums/1...-f600-4x4.html
https://www.ford-trucks.com/forums/1...00-engine.html

 

The VO might be good, you'll have to find a truck salvage outfit to find one and it may need a rebuild:

I looked at the usual places and found none.

A 389 is a smog version of the 391. It may have a cast 390 crank vs. the steel 391 crank.

You could put FE heads manifolds on it which would give you bigger valves etc. But you shouldn't spin it much past that 3700 RPM governed speed as these use a heavier piston that may not like the RPMs so much.

That truck wasn't meant to be a freeway flyer and you'll spend a lot of money making it one.

 

about half the time bobtail & other half pulling a 30" gooseneck with a small dozer or a Case 580 D backhoe, not planning on high speeds down an interstate but cruising at 55-60 on a 2 lane with motor not running against governor.

 

Perhaps it should be put "in service" and do some real time evaluations.
The modifications you are considering are a pretty good undertaking. both time and money-wise.
580 weighs 5,200# and a D4 weighs 30k # (to me a small dozer is a D4)
Sounding like you will be pushing the limits of a F-600 and could really use something with air brakes.
But, you could have experience nursing trucks like this along. I have done exactly the same thing with a R-190 International, back in the day.

 

JD 350 B dozer, I don't remember what it weighs but am sure it's a lot less than a D 4 . on a scale of 1-10 ; one being all decisions are based solely on practicality & cost benefit ratio , ten being this is my pet bucket list project where cost is no object !!! I am probably at a 6 !!

 

___________
I kind of understand. 12210 lbs (5,538 kg) is weight on your dozer. I think your truck will pull it, may just be a matter of getting it stopped.
I love hanging out with my friends where money is no object. I'm usually the photographer.

 

Hobohilton & 85e150 : I delved into the info you both provided including the 3 links that you supplied , wow information overload !! 85e150 suggested installing FE heads on my 389 block, I assume that the heads, intake & exhaust manifolds from the largest CID of the FE family would therefore provide the most cfm potential ? all my engine experience has been " as is " never any modifications thank you

 

The FT intakes are 1.75". 1972 and later (as oem these had hardened exhaust seats) 360 and 390 heads have intakes that a little over 2". Exhausts are little bigger too.

427 heads would be a waste of money, and 428 heads are the same as 360/390 except for CJ heads which do not have the hardened seats and would be much more expensive.

Not sure on ports etc.

Exhaust manifolds are a weak spot but with the engine speeds you have and in the truck chassis, you may have to keep the FT manifolds. Or shorty headers for a pickup.

A stock iron intake manifold will worked. Those marked S or T work well.

A 500 to 600 CFM carb will work as you are not spinning the engine that hard and you want to keep velocity up on the intake side.

As to cam, you have other posts on that.

You can keep your distributor but should probably have it recurved and get an electronic kit for it.

You will still be RPM limited, but will get there a couple seconds quicker.

 

They are neat trucks, but were never designed or intended to go that fast. they are made to haul weight, and with the gassers they were geared low to make up for the lack of power. On flat ground you may get some speed up if you overdrive it, but as soon as you get near a hill you'll start dropping gears. The best thing you could do is put in a diesel, 5.9, 8.3 cummins are the most common, but detroits, internationals, and just about anything that can fit have been done. Your axle gearing is also a big limiter, usually 6 or 7.something low gears. Not much available for them gear wise. Newer axles might be in order. It's a cool project you if it works as is and you don't need to run it often, it might be better off to just enjoy the sights in the slow lane. I had a few of these, got rid of them and plan on converting a 2wd 77 f600 to 4x4 using modern f550 axles.

 

I am not wanting to go fast , just lower my rpm at 55-60 mph with an overdrive. Based on the fact the truck is not overpowered now makes me believe that I need a modest increase in torque. .I think I need to start from scratch on deciding which engine I have now . Here is for certain : intake manifold extends under the valve cover , 5 bolts on said cover. cast iron intake manifold # D5TE 9425 TA , only other # that I could find ( without removing IMPCO carb ) was the firing order. Please tell me if I need to look for any other # 's & where to look.

thanks again for your time & patience

 

You have an FT engine, probably the one that came with the truck. (Only the FT and FE have the manifold under the valve covers. 5 valve cover bolts is another indicator)

What is the 4th character of the VIN?

How did you originally come to the conclusion it was a 389?

 

decal on air cleaner & decal on r.h. valve cover , I incorrectly read some old posts that made me think that only FE engines had intake extending under valve cover !
when I go to shop tomorrow I will send you 4 th character . since I have already messed up your evening mechanic job ( putting rear end in a easy chair ) why is the 389 called a 'smog engine ' ? externally all I see is the PCV system & that decal on r.h. valve cover talks about emissions or something to that effect thanks again !

 

Never mind, if this is the same truck:

https://www.ford-trucks.com/forums/1...l#post18247603

 

bingo yep that's it