Boosted Willys - F134 Engine Swap with a twist

I’ve been busy working on my wiring diagram and collecting parts.

I’ve been doing some reading on fuel injector impedance and found that because my single tbi injector has low resistance injector (1.5-1.6 ohms) I’ll need to add an inline resistor to limit the amp draw to 2 amps. Not a huge deal, but something that needs done so the driver on the Microsquirt board doesn’t burn out. 

The other thing is supercharge cam profile theory. Through some intense google wormholes, I found an article that seemed to break down the submit to a relatively simple manner. 

http://www.enginelabs.com/engine-tech/inside-forced-induction-camshaft-designs-howards-cams/ 

As fate would hate it, Howard cams is in the same town as me, so I paid them a visit to see what they thought on my project. While they do have a good bit of experience with forced induction cams, they don’t have capacity at the moment for custom cam grinds. They passed me on to a Steve Demos in Georgia to see what he might be able to do. After a lengthy phone call to Steve, it sounds like he’ll be able to weld up and modify a factory cam to give it a little better lobe separation and exhaust duration to get things flowing better. 

I think it’s interesting to try to squeeze some more power out of it. The main thing with a supercharged cam is the separation in the lobes between the intake and exhaust lobes to make them open further apart. 

I have been talking to that guy actually. He’s engine setup is nuts. He’s pushing like ~150hp and 8,000 rpm 

Him and I have mainly need talking about setting up a head with roller rockers since the stamped steel ones are a weak point in the factory valve train. I think with a bolt in mounting plate, big block Chevy rockers would be made to work and increase the rocker ratio from 1.3 to 1.7 and give a bit more lift out of the intake side. I’ll have to see what can be done to the duration of the exhaust side to get that to flow a little better. 

Haha well all this stuff “bolts on” it just doesn’t come with a clear set of instructions. That’s were my process engineering degree comes in handy to figure that part out. I’ve spent entire days reading about simple things like fuel injectors to figure out how to make them work and just being a naturally curious person. 

But you do pose a good question about the power curve. These L head or F head engines are what’s referred to as under-square meaning that the stroke (4.375”) is larger than the piston diameter (3.125” @ standard bore). 

Historically, this arrangement makes good low end torque as seen here on a power curve on a stock engine. 

Horse power in white

Torque in orange 

My intention would be to keep the curve relatively the same shape, just increase the power output. I actually mainly street drive my Jeep, so I’ll likely regear the axles to 4.88 ratio to give me better top end, but still want modest power down low to make it work well off-road. I think my goal is a modest 100-100hp overall.

That's not to say that sticking a turbo on automatically turns a screamer into a stump-puller.  But it does show that forced induction can really help low end.