Diesel

Wrong word, they are unreliable and the quality is not good.

98jeepster

Ok ill never buy one then but I would just build one and super charge a stronger block without stroking it and you will still get good gas mileage and dailly driving

dukie564

supercharger?

there's no replacement for displacement, and a supercharger is going to cost waaaay more than a stoker build ever would. Not to mention you would need to upgrade engine internals anyways to handle the constant increased pressure of the sc. Also more parts to break.

And a supercharger will not give you better gas mileage than a stoker...

Gee oh Dee

If anything you'll probably lose MPGs.

98jeepster

This company did it and di a test on it and it was in a amagzine it gave it good torque and horsepowrr and added three more miles to the gallon and it was on a stock4.0 but it was an eaton super charger

Gee oh Dee

Link to this info?

dev_daddy

Don't put all your trust in a dyno test.

98jeepster

Well they actually trail tested it and all

lolzabee

You won't have to build the motor. Especially with the low compression of our 4.0s and iron block, it's actually set up pretty good for boost right from the factory. Definitely would require better cooling and tuning but otherwise ready for it. You can get a used eaton blower from a supercharged buick and custom build the brackets and pulleys. After that, new injectors, cooling, and tuning would be all you need to run the low boost of that blower.

Diesel

What, like 5 psi? What a dramatic increase....

The engine needs to be set up properly for forced induction, 3-5 psi would probably be ok........for a while, dont go higher unless you want to upgrade internals, ie. pistons, rings, valves, rods etc.

Mileage is also something to account for, 100,000 is alot of wear on a engine, possibly too much to bother adding a source of forced induction, especially if its going to be driven hard, a turbo will slowly wear the engine on stock parts anyway, with 100,000 miles of wear its not going to have loads of years left in it with a turbo/supercharger.

Even if you decide to not upgrade internals, youll still need tubing, silicone hoses and clips, intercooler, BOV, wastegate, turbocharger(or supercharger), turbo housing, manifold, injectors and fuel pump, and ECU tune/remap to run it properly.

Stroker motor is cheaper, more reliable, and the obvious better choice.

lolzabee

5 psi on a 4.0 is going to make you a bunch of power. How much depends on how radical you tune it, but a safe tune wont cause your engine to fail prematurely. Compression on this engine is what? 9-9.5:1? I forget. Most built for boost engines aim around 9 unless its being built for a ton of boost. Nissan 3.5 engines (where my experience comes from) easily make an extra 100hp with 8 psi., adding 50-60 ft lbs at 5 psi on a 4L would be cake on a super conservative tune.

Obviously you are biased against boost for some knowledge, probably lack of experience with proper setups, but it is very easy and quite cheap to build a low boost setup. If you have any fab skills, this could be done for under $3k, I bet under $2k if you do it wisely and less if you go cheap on some stuff

Roots style blowers (the eaton I was referencing) don't require all that BS you were showing. They require a BOV, which IIRC is built in, more fuel, and a tune. You don't need an intercooler, turbo housing, manifold, silicon hoses and clips, wastegate. Please read up on roots blowers before you make assumptions.

PS, Buick put these factory on motors that were not "built", just low compression like the jeep motor. They are not intercooled. Basically the only difference between the SC motor and the NA motor was the SC, injectors, and tune.

lolzabee

I would feel comfortable boosting a stock block 4.0 to probably 10 PSI or more. Low compression + iron block makes it very reliable for boost.

dukie564

ok before a pissing match starts, the OP was talking about a stoker, not a supercharger/turbo.

I can comfortably say that most people agree that a stoker is by far the cheapest and safest route for more power on the 4.0. Yes, there are other options, but they are not as easy to get operational or as economical, and also not as reliable. I'd say a stoker simply suits the needs of 98% of jeepers who want more power.

98jeepster

Well if I ever really need more power I would build I stronger block and head run ten pounds ona super charger and a good standalone and tune and etc so I would be happy with it and I have toyota supra I have built and I know alot of turbo stuff but allways wanted to try a super charger out on something but yes a stroker would be alot cheaper

lolzabee

Stroker would def be cheaper if you can do the build yourself (minus machining of course). I'm just trying to offer more options to the OP so he doesn't buy into the BS about SCs from people who don't understand it. Personally, of all the choices, I would do none. IMO it's either stay stock 4.0 or go for an LS1 with RV cam and etc.

By the way, how can you say a stroker is good for 98% of keepers needs when nowhere near that % even have similar needs. Mud trucks won't appreciate a stroker nearly like a rocker would. Not to mention a mud jeep would appreciate boost quite a bit, spinning high RPM and all.