My son has a 1984 f150 supercab long box, It has a 5.8 windsor.
He is thinking of swapping a 5.9 cummins or a 4bt.
We are planning on swapping out the ifs for a dana 60, so thats not an issue.
Truck is mint, frame is clean not so sure about the 5.9 in that frame as far as twist.

Any ideas would helpful.

 

I would pony the extra up for the 4BT myself, it is strange that the 4 cylinder is a couple grand more than a 6 cyl, but that reflects the popularity and ability of the little 4.

Either will twist the frame, so just figure on it. Those early f150 frames were mostly Swiss cheese when new, some of the lightest trucks ever built.

Hate to say it, but I would probably find an extended cab F350 frame and do a body swap.

In any instance, check out 4btswaps.com, lots of good info.

 

I'll check it out thanks