I'm rebuilding the engine, have it all torn down and figured i might as well see what I can do to get more horses out of it. I read some stuff about cams, exhaust, intake, under pulleys , and I'm just getting confused. What should I do to build this motor without spending an absolute fortune?

 

There are a lot of things you can do to get more power. Most of which takes considerable cash and sometimes causes issue with street ability. You can go to a different cam but that usually requires other changes to get the most out of it. Engines need to be tuned (I am not talking spark plugs and timing) to get the most out of it. Ford has tuned the 4.0 SOHC pretty well for what it is intended to do. Once you change one thing it is no longer tuned. Sure you can add headers and that will not have huge affect on tuning but you don't get a big change in power either. You usually just shift the peak torque rpm range, unless you do enough to the engine to significantly change air flow through the engine. Under drive pulleys just reduce power loss by slowing down the things it drives. That can have some bad side effects like tending to over heat at idle, especially in hot weather. Going to an electric drive fan is probably the best thing if you want to reduce a little power loss. Just know that is still takes power to run an electrical fan. You can just control when it is being used.

One thing you can do increase power without changing the physical part of the engine is with the Engine Control Module. There are companies and individuals that can change the programming of the ECM to get more power. This changes the electronic tuning to get the most out of your stock engine. It can also be used to get the most out of a modified engine. I use a programmer to reflash the ECM and have 4 programs to choose from, including the stock one. I can't recommend a tuner because the guy that did mine is no longer doing it, at least to my knowledge.

 

I met a guy at the gas station last summer that said he changed the intake, exhaust and ECM and was pushing 300 horses, but I don't know exactly what he put in. Wish I would have got his number.

 

I met a guy once that told me he had a Ranger that came from the factory with a V8. He was full of baloney too.

 

Well this was an older retired guy. Truck was in showroom condition. didn't get the impression he was B. S.'in me.

 

I am also an older semi-retired guy and at 73 years old, I can tell you us ROFs are pretty good at BS. We have plenty of experience with it when sitting around the campfire.

Go ahead and put on that intake, exhaust and ECM. Let me know how that 300 hp works for you.

 

Have to agree with IN2 FX4 here
Not sure the ROF believed what he said, but I am sure he knew it was at least stretch of the truth, like 215HP is almost 300HP, lol

The 4.0l SOHC is rated at 207HP, and that's with 93 octane, maybe 91, its 9.7:1 compression ratio so WILL ping/knock on regular 87 octane

You would not get 33% more HP with listed parts

How you gain HP is simple, very simple, you burn more gasoline in a good air:fuel ratio on each RPM

A 6.0liter has more HP than a 4.0liter because it can burn more gasoline on each RPM

A turbo or super charged engine has more HP because you are stuffing more air in so can burn more gasoline on each RPM

So very very simple on the way it works, you need to add MORE AIR to each RPM to add more gasoline to get more power

A cam can help because you can get a bit more air in, not much but not 0 either
Porting can help because air is less turbulent so maybe a bit more air as valve opens
But these might get you 5%-8%, tuning maybe another 2%-3%

4.0l SOHC is not a good engine for turbo or super charging because its running 9.7:1 compression ratio
You want an engine that runs 8.5 to 9.0:1 ratio, these are OK to add boost to but there are still issues

 

The old stock Rangers have plenty of power . If you're just looking for a little fun may I suggest a 100hp wet NoS system. You can put a switch so that it only sprays when the TPS is at full throttle. Just don't let it spray very long or you'll be buying a new engine.

 

Increasing power can also be done without turbo/super charging or NOS but they are probably less expensive. I doubled the power on my Austin Healey Sprite race car engine. That old fashioned, push rod, 1.1 L engine pumped out about 55 hp stock. It now pumps out closer to 110 hp and that is not old guy BS. What it took was bumping the compression ratio to near 15 to 1 (requiring 110 octane race fuel minimum), a flowed head by one of the best professionals, modified combustion chambers, larger valves, high lift roller rockers, stronger valve springs, radical cam, flowed intake manifold, modified side draft carbs with air horn intake, custom tuned header, custom exhaust, custom pistons, high voltage ignition system, dyno tuning and many things to get it to survive at 8,000+ rpm. It doesn't start to make decent power until 5,500 rpm.

So, it basically gets it power also by increased air flow as pointed out by Ron. It just does it by increasing rpm, reducing air flow restrictions and taking advantage of the dynamics of air flow. Increasing efficiency of burn with higher compression helps a lot too.

It would be easier to slap on something to pump more air in or NOS but when racing rules do not allow that, you go my route.

 

Good job ! Personally I'd rather go with lower compression pistons and NoS. It seems to be better on the bottom end of the motor and I can drive it everyday. I've built some Old School 340's and 440's and shaved the heads and used domed pistons to get 12 to 1 compression but detonation was always hard to get rid of even with high octane fuel and I didn't like water injection. Getting Revs is where it's at. Bigger bores with shorter stroks lets you rev higher. I'll look for the formula that tell you what bore and stroke gives you in cubic inch and RPM potential. Carroll Shelby was a "no replacement for displacement kind of guy" . Me too !