I don't know if anyone can help me with this. I have a 1998 E250 it has a 4.2, (well a blown 4.2) I was wondering if anyone has tried to put a 4.9 in one of these. They are the same transmisssion and it looks like the wiring harness would plug in? Any advice or should I go with a 4.6l? I'm not a fan of the 4.2's.

Ford put 4.9s into that body, so it will physically fit. One model of transmission can have several bellhousing castings, so I can't confirm or deny that your original trans will bolt up to the 4.9's smallblock pattern. If the 4.2 is unique or modular, it won't. Even if the connectors are the same shape, the wiring pinout probably won't match, so plan on some wiring modifications. This isn't a popular swap, so it'll be ALL YOU figuring which wire needs to go where. I've done this type of thing on 4 vehicles now, so it CAN be done with patience & persistence. Click my signature thumbs to see some of them...

You are in luck as the 4.2L shares the 300/302/351w pattern and not the modular type.

How about a 4.2 to a 4.6 swap out? Will this plug right in?

Same for the 4.6L:...but for that, adrian says you'll have to change the transmission, unless you find a rare 4.6L w/2-bolt starter in decent condition.

I think you should consider buying a van that already has the engine you want in it. I think you're setting yourself up for a tremendous headache trying to a swap a 300 in place of the 4.2 liter.

No, the 4.6/5.4/6.0/6.8L share the different modular bolt pattern. Like steve says there were some early '90s 4.6L in the crownvic that had the 300/302/351w/4.2L pattern, but your askin for a lot to make that happen.

Adrianspeeder

In the CV, the 4.6L had the smallblock bellhousing pattern only for a few months in '92. IDK if Ford used those "bastard blocks" in any other vehicles.

So I'm assuming the best thing to do is replace it with a 4.2? I was trying to excersie other options as I'm not a fan of the 4.2l.

"Best" thing??? That's up to you. "Easiest"; probably.