I was going to turbo/rebuld my carbed 300 (1978) F250 Np 435. I now am looking at a 3.9 4bt cummins. I heard that they aren't that much heavier than a 460, so my truck should "hold" it just fine. I just can't decide. The 4bt can be modded just like the 5.9 so getting 250hp and 400ft/lbs out of the little guy should not be a problem reliably.

How does a 4bt fit in the 78 2wd chassis, would it be a large job like the 5.9
or is it relatively simple?
How much fab work would it require to put a 3.9 cummins in my 2wd f250?
would it be as "streetable" as a 225hp turboed 300?
will the 4bt in 250hp flavor distroy my running gear?
What year 4bts are the most desireable? can I put a 4bt infront of my np 435, and 4.56's, if i go 34" tires(265/75R19.5H) and a GV oD unit, and still run with traffic?
pros/ cons if I missed any???
Thanks
Dustin

 

fellas???
I'm still here

 

I'd check with fordcummins.com I can't think of a better resource or more knowledgeable guys about a Cummins swap into a 73-9 F series

 

Is there an aftermarket "Turbo Kit" available for the 300 Six, or would you have to develop and fine-tune the system yourself? If there is a developed kit available, I would go with rebuilding and Turbo'ing the 300.

 

I think it will probably be a developed kit with an HX 35 off of a 98 12v cummins, rebuilding it and buying the needed plumbling from an exaust shop.

 

I would do the 300 six and a turbo. How cool is that!?!! You will get great torque when tuned right. Sound awesome too with the turbo spooling up.