can i do a 4.1 to 4.5 swap my uncle has a 88 with a 4.1 liter and would like to go to a 4.5 is this a resonable swap.

Yes you can put in a 4.5 but why not a 4.9? The 4.1/4.5/4.9 are physically identical. To make it work use the intake manifold from the 4.1. You will also need an adjustable fuel pressure regulator to dial in the extra fuel that the larger cubic engine will demand. Good luck

Yep, a 4.9 is the way to go if externally they are all the same. I have one in my '93 Eldo and it has better seat-of-the-pants feel than my wife's Northstar.

George

We have put a 4.5 in to replace a 4.1 a couple times but never used a 4.9. The last 4.1/4.5 replacement had issues with fuel injection control. The computer kept leaning out the mixture for some reason and there was a stalling problem. It is OK now but still not quite 100%. I bought one Allante' '87 parts car with a 4.9 installed that the guy could never get to run right. I never looked into why. It was too rough overall to bother with.