Hello i have a 92 F150 4x4 with the 302 EFI in it. The engine has very little power and im unhappy with its performance. Rather than upgrading this worn out engine id rather buy and upgrade an older 302 carbed engine. Much easier to work on. Will this bolt right up to my current transmission and what all would i need to change, such as throttle cables/brackets, Manifolds, ignition boxes, etc.

 

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Ok, for starters, swapping to the older setup is a major downgrade for many many reasons. I fail to see how a fuel injected vehicle is harder to work on than a carbed setup. I can see how someone might be more comfortable with the older setup, but they are not easier to work on. Fuel injected vehicles require virtually no adjustments, and only basic maintenance and an occasional sensor. Carbed vehicles require frequent tinkering and adjustments. They use a complex set of jets, and the mixture is regulated by moving mechanical parts that are prone to variation from moisture, air pressure, temperature.

Fuel injection is the number one reason why modern engines can last hundreds of thousands of miles, while older carbed engines show they are tired beyond 100,000 miles. Sure there are exceptions, but typically an older carburated engine wears out faster.

I would pull the old engine out, inspect all its parts, rebuild it, and because I am this way, I would do a lot of detail work on the head to optimize flow (then again I have the tools to do porting), and build it back to stock specs. I would then enjoy it for another 20 years.

Common issues to look for. These have old cast iron heads. The valves tend to wear out the seats, and the valves will then warp and recede into the head, causing a low compression issue. Often the heads crack when this happens. If your heads are not cracked, have the stock seats cut out and replaced with hardened alloy inserts. Much tougher than the stock seats, and makes the valves last longer. Obviously I would have the heads resurfaced, and if the whole motor is out, I would consider having it decked too. I would have the cylinders checked and at the very least rehoned, If they require boring, then junk the motor unless larger pistons interests you. New rings, and it probably would be a good idea to replace all the engine bearings and just redo everything.

The end result is an engine that is better than new. I would do all this if I was running a carbed motor too. Break it in hard, they last longer.

Now obviously you could just swap a used motor in an not rebuild it, not sure it would really save you any money, since you are just hoping and praying that someone else's piece of junk is in better shape than yours (fat chance, its in the junkyard)

The main problems with carbs is poor atomization, which causes less power, fuel economy, and it washes the cylinder down, which causes them to wear out way prematurely. There are tricks to improve atomization, but at the end of the day, fuel injection requires much less maintenance, no adjustments, and fewer reasons to even have to work on the engine.

You will likely spend as much or more to find a carbed motor and all the necessary parts that are different from yours, just to get an inferior setup. Unless the vehicle was a collectors classic, I wouldn't bother.

 

To add some items, if you have an EOD type trans, you have no way to control it.
If an AOD type, you need cable linkage from the carb to vary the front pump pressure vs throttle position.
The fan and water pump turn the oppisite direction on an original carbed motor.
Too many differences to make it an easy swap and negate the original reason for the swap..
If you do the older motor to FI you can have an issue with the OX sensor vs cam/ignition fire order. They are not the same.
You would need a 351 flat tappet cam in a 302 to satisfy that requirement if using two Ox sensors, otherwise you will get rough and hunting idle.
The truck cam usually has shorter valve duration events for low end torque a car cam does not usually have.
Been there years ago from retrofitting a 72 302 to Mass Air FI.
So you see, either way it's not so simple considering all the differences and the possible outcomes..
As far as bolt up, yes the blocks are the same pattern.
Your better off getting a rebuilt short block and doing the heads and be done with it.
As far a making more power, it can be done to a degree but you have to selsect the changes to stay within the 'Speed Density' system of operation.
That means the cam has to stay with a large lobe seperation of at least 114 degrees or higher or intake vacuum drops and idle goes to h*ll in a hurry because the MAP sensor controls most of the fueling by sensing intake vacuum.
Good luck.

 

Moved to correct forum.