Hi all!
I am thinking of doing a a 5.4 swap into my 76' highboy. Not worried about electronics, got that covered. My concern is width-mods are massive and i have the narrow frame. I am just curious if the swap is feasible. If so, has anyone here done it?

 

I did a 4.6 into one.

The valve (cam covers) just about touch both the brake booster and the heater box (AC cab). There might be 3/4 of an inch clearance on each and with the 5.4L being wider due to the taller deck height, there may be an issue with yours. There is a smaller diameter booster available but if you have an AC unit, you may be in trouble.

That's not to say yours will have clearance problems though. My engine mounts might position the engine a bit higher...since they're obviously custom pieces.

 

Awesome! I am going to be running a vintage air setup so hopefully that will solve that issue. I am going to do the 4 valve Navi engine so, i will need all the room i can get. Not sure what I am going to run for a tranny. I would like to stick with a granny low manual but who knows lol.

 

Definitely possible. I had to run a hydroboost to get quality brakes with my 2013 5.0 because I could not fit a larger brake booster.

 

Out of curiosity, what do you do with the electronics to get a 5.4 to work in an old highboy? I would love to swap the 400 out of mine to something more modern, with efi.