258 supercharger ?

im getting my 258 out of the shop friday with a fresh rebuild and am wanting 2 supercharge it but dont know how or what 2 get i want 2 keep my carberator and just and the charger what do i buy and who do i buy from DO THEY EVEN MAKE SOMTHING LIKE THIS LOL

 

I dont think anybody makes a bolt on supercharger kit for the 258. Especially one that will use the stock carb.

http://www.jeepaholics.com/support/topic.asp?TOPIC_ID=55659

 

If you can adapt a supercharger to a 258 you'll spend $5K and have an engine that has some bottom end and a lot of peaky power. You could make a lot more power with gobs of bottom end for a lot less money by simply putting a different engine in it. It might suffer detonation, would require a pressurized fuel system with a regulator, would not enjoy being lugged, would run hot, would likely require high-test gasoline, would require you to reduce the compression ratio by some means...big pain in the butt. I considered forced induction on my E30 BMW and determined it was not feasable. And it makes a lot more sense on an E30 than a Jeep. My conclusion with the E30 was that an engine swap was way more practical. In the end I did neither, accepting the E30 for what it was: a light small car that can corner like nobody's business and didn't need a lot of horsepower to make it an outstanding automobile. I think straight-6 Jeeps are also cool as hell based on accomplishing a design intent without a lot of baloney. It's torquey as it needs to be, rugged, simple, easy to work on. That's what a Jeep is all about.

Chilly

 

Now if you wanted to do it anyhow, I think the thing to do would be to swap in a fuel injected 4.0, or do a 4.0+ by installing a FI head on a 258 bottom end. I know they make a supercharger kit for a 4.0. And you'd need a pressurized fuel system from the tank to the fuel pressure regulator. It would not be a terrible engine by any means, but I think for low end grunt a larger displacement V8 is the ticket. For the same money you'd invest in a supercharged I6 you could have one bad V8. The broad flat torque curve of a V8 is very predictable. A forced-induction engine tends to be somewhat unimpressive then all of the sudden comes on strong. Supercharging isn't as bad as turbocharging in this regard but it still takes some revs to make boost.

 

Re-read your post. I don't think you'll find any option for supercharging with a carb. That's way old technology. Anyone making a supercharger kit will assume the owner is serious enough about performance to not bother with a carb. Not bashing your idea, but it's sort of like installing a locker in an AMC20 but insisting on two piece axles. Also, boosted engines are typically built with lower static compression ratio so the dynamic pressures don't go througfh the roof under boost. If you don't drop the CR you'll probably have to intercool it to control detonation. That's an even more complicated kit with a lot more expense. And I do not know if such a 4.0 kit exists.

You've got a newly freshened 258. That's pretty cool. If I were you I'd bank the money or install some ARBs, a Warn winch, and some new tires instead and still have money left over for an offroading vacation.

 

If you are looking to spend money on that fresh engine, I would dump the carb and install a fuel injection setup. That alone woke my 100k engine up quite a bit. If that isn't enough, put a 4.0 head on that was mentioned before. I did the affordable fuel injection swap and the throttle response is awesome. The MPI was a little spendy for my taste.

High5

 

If I was going to spend money on an I6 (as said V8 would probably be cheaper), I would stroke and FI it. A stroked engine gives incredible torque at low RPMs and the FI is a no brainer for anything that operates on a slope.:v6:

 

7 years ago I put a '91 4L H.O. (casting #7120) head on my 89 258, and a mopar efi kit, 4L headers and catback, was able todo all the labour - best $ I ever spent - all I can say is "it woke that engine up"

an engine nonjeep swap meant (for me) new motor mounts (welding ) , dont have hoist and other things beyond my capability so I would have spent $ on someone else doing labour ...

this way got a setup I understand and its still mostly all jeep parts .. vroooom

edit: 4L's are more plentiful now - there may be swap writeups published out there so you know what your getting into ... I have an engine hoist now

 

This is a picture of my 73' jeep cj6. the engine is a stick 232ci I6. I have installed an Eaton M90 supercharger out of a mid 90's ford thunderbird super coupe. This system to date is working very well. I don't have a dyno so i cannot give the exact HP/TQ increases but i can say it's HUGE improvement. It now has the power to spin 35" interco tires in gears i havn't ever been able to use effectively. The system is very simple. I fabricated the plumbing for a "draw through" design using a holly 500cfm 2bbl carb with a 50cc accelerator pump. I replaced the stock pulley( with the help of a shop press) with a standard 2" v-belt pulley w/ 5/8" keyed bore. The bore did need to be machined out a few thousandths to make for a nice press fit to the shaft. This jeep came with a single v-belt that drove the water pump and the alternator. I installed the blower in line with this belt. I then installed an idler pulley to bring the belt over some so it would have more surface contact with the water pump and prevent slippage there. I made the idler pulley to have some throw so there would be extra room for adjustment. Then i made a trip down to the local farm supply store and found a belt. I put the belt on, cut a hole in the hood and turned the key. I havn't made any adjustments to the carb or to the timing And it runs and drives perfectly once operating temp is reached. when it's cold it can studder a bit if you try to get on the throttle but i won't attribute that to the blower seeing as it did that with that carb before the blower was installed. It starts easier and idles/runs smoother. It should be mentioned that this jeep was built for off-road only. it has 3/4 ton ford axles)4:10s) and a divorced 205 transfer case added to make a "doubler". For that reason I cannot say for sure what road manners of the supercharger would be like. However, i speculate that is would be just as good on the street supercharged.IMG][/IMG]

 

I'm very impressed!

 

awesome work!

 

Thanks guys

 

Hey all. I have a 79 258 I'm looking to blow with the same supercharger as pictured above, the Eaton M90. Does anyone on this forum know how or if I can get in touch with SawedOffCj6? Looking to very closely follow his steps but looking for more detailed information. Thanks!