2.9 to 4.0 swap

[lil_Blue_Ford]

Good stuff to know going in. I will be using a complete donor car so I am sure to have all the necessary widgetts to complete the swap. My inclination is to use the cammer but that is what I would want if I was driving it. My granddaughter doesn't need the HP and would not know what to do with it if she had it so logically I should go with the OHV which probably has more bottom end torque anyway. For reasons I have not tried to figure out cam in block engines generally have better bottom end than cam in head. One of lifes mysteries. Tire size is the original bronco 215/75/15

The SOHC definitely has more power, but also more issues. At least in early generations. The OHV, especially with a little work will be plenty adequate in a B2. Heck, a mostly stock 4.0 in my Choptop B2 on 35’s will bark them. If you want to dive into the engine, there’s things like balanced internals, cam, free floating rockers, flow port, headers…

Also, the OBD2 system uses tire size for a lot of things, so that has to be adjusted to suit what tire you use if you go to OBD2. If you stick with the old system, then speed is governed by the gear in the output shaft area of the t-case

I have an acquaintance in the midwest who tunes via the net so I will need to contact Andy to see if he can dial this thing in when I am done.

If I have a complete donor truck, that should solve the speed sensor issue. I would want to change both ends because having two different gear ratios would not be good if that is a possibility.

So, the 95-01 Explorer and 98+ Ranger use a different front end that isn’t compatible. They would still be ok donors if you can match gear ratios. The 95-97 Ranger would be your only choice if you want OBD2 and everything that is reasonable compatible.

Also the newer donor truck should have anti lock. The current Bronco does not and she will be driving in snow at college. Front disc rear drum. Possibly adding that?

She will probably be driving this for many years to come so doing all I can for safety and longivity is a necessity.

Thanks for all the info. If you think of anything else please send it my way. The more I know going in the less I need to figure out in process.

My mind often follows very strange paths and It just occurred to me, what about lifting up the existing body and rolling the new chassis under it? I have done stranger things.

Personally, I’m not a fan of anti-lock, especially in the snow.

There really is not a an ideal frame donor that I’m aware of.