4.0ohv to 2.9ohv

[Zaon Prime]

Hello my fellow Rangers and Gang,

I have a 91 ford Ranger XLT 4.0L M50D 5sp 4x4 extended cab. I had some oil leaks and pushrod ticks so I pulled the motor to do a complete reseal and check the lifters, pushrods and rockers. Well some of the push rods were mushrooming. The lifters i received when getting parts were flat tappet instead of the roller lifters that are in the motor and at the time i wasnt able to source a full set of push rods and rockers.
I have a Melling upgraded oil pump a complete reseal kit, arp head bolts, I am planning in buying a Morana Roller Rocker kit. To improve oiling and prevent pushrod mushrooming. At least attempt to.

That being said the Morana Roller rocker kit is $1600 USD that kind of money dropping all at once is not something my wallet can handle at this current time.

I have a 2.9L that I acquired through a buddy who Chevy 350 swapped his 88 Bronco.

my idea was to throw the 2.9 on the truck to get around town while i clean, reseal and upgade to the roller rockers.

I already know the 2.9 will bolt up just fine. However I have only ever seen people upgrade from the 2.9 to 4.0, and not vice versa. Logically you want to put in the beefier engine.

What all do I need to do to swap it over just to get the truck on the road. God i miss driving this truck and I am tired of asking my buddy to borrow his Chevy to do truck things

This Ranger is my first ever vehicle. The engine used to run so silent at stop lights i would think i stalled and ruined a few good starters and flywheels. Burned through alot of clutches too haha.

Also what are your thoughts on the Morana Roller rocker kit?
Do you guys have any other recommendations?
Thanks.

I am Subaru Technician. I practically do headgaskets on a weekly basis.

 

[franklin2]

You could do a full rebuild on that engine for what you want to spend on those rockers. There are millions of the 4.0's running around with stock rockers. Not worth it in my opinion.

I just swapped in a 2.9 where a 2.8 lived. You are correct, it bolts right in. But it's the wiring and computer that will get you. I would not put the 2.9 in place if you are planning to go back to the 4.0 later.

 

[SenorNoob]

I agree.^

Though I do wonder now if a mass air 2.9 PCM would work with the 4.0 harness?

 

[lil_Blue_Ford]

I agree.^

Though I do wonder now if a mass air 2.9 PCM would work with the 4.0 harness?

The problem is that the 2.9 was never coil pack ignition and the wiring all different to run the distributor and coil.

 

[bobbywalter]

yeah....just get another 4.o

or a 350.