Love my built 258, but the day is coming sooner than later when sniffer testswill be away of life, so to have an enviromentally cleaner ride with tranny spinning torque, I am thinking about adding a late model injected Ford 300, since I am alreadyrunning an NP435 out of a fi50 and the bellhousing and flywheel are in the garage, it seems like a reasonable swap, has anyone done this or offer some critique on this line of thinking.
Tom

As 6's go, the 300 is a large beast. I've helped install one in a Toyota FJ40 Landcruiser, but never in a jeep. Don't know dimension wise how well it would fit. Might be a tad tall, but not sure without actually sitting down with the measurments. As far as the engine goes, they are top notch. I've owned a couple Fords, F150 and F250 (high-boy) with the 300 in it. Probably the best engine Ford ever built. If you do drop one in, talk to Clifford Performance. They can make that 6 REALLY shine!

the 4.0 can easily outperform the 300 in all reguards.. and you have the parts to make it work.
1. Buy a 4.0 from a guy I know here.. they sell for under $1000 with the wireing harness, computers..everything.
2. put your 258 crank and rods into it and use 97+ dished pistons.
this will give you about 250 hp with 9.4-1 compression ratio(around 270 ft-lbs torque)
you'll also be swapping in a newer jeep engine, so it should be legal almost everywhere.

This is a great topic to do a search on, lotsa good info available--it's been discussed 3-4 times in the past 1-2 years.

I disagree with elusive--I think if you compare stock to stock, the 4.9 will outshine the 4.0 in every department, and if you modify both equally, that will continue to happen. The greater displacement really helps. Of course, if you stroke a 4.0, add headers, intake, etc., and compare it to a stock 4.9, it may be a different story. The emissions point is irrelevant if you're swapping to a late model engine either way--and either way you get fuel injection. Parts are cheap and readily available, as are the engines. YOu could probably find a wrecked F150 with that engine and get the whole truck for $1000.

I'm a huge proponent of the 300. That said, were it me, I'd still go with elusive's plan. The PITA that you will have trying to cram a long 300 into a short CJ engine bay will outweigh the benefits. Yes, there are guys who have done it, and someone had some pics at one time...but it would be simpler (although probably not cheaper or more expensive), to swap in a 4.0. And even if a built 4.9 would have an edge, a built 4.0 should provide all the thrust you will ever need. Like elusive said, you've got all the parts to make it work. I think he's got the winning idea. Engine mounts, cooling, wiring...everything should be simpler.

Sounds like you already have the plan!

That little 300 is a great choice for torque and longevity. It's a real work horse!
Buy one now and go through it at your convenience, have it ready when your 258 goes away...
Now that you have all the time in the world, you may even find one in a junk yard with VERY low miles on it...

You have a well though out plan, and now you just have to act on it.

Heh little 300.
The 300 is a brute in all regards, massive block. Big torqe. and torque is waht you want if you want to ty to turn 44s. if you want inline tech talk got to INLINERS.ORG
These guys are the place to go when it comes to inlines that make gobs of power. There is a FORD area that would be able to point you in the right direction. Seems to me that someone there said that 450 Hp is very attainable for the 300 six.

Jesse

The big HP is attainable--but at high RPMS, which are irrelevant for rockcrawling. As you said, torque is king. The 4.0L is an inline engine as well--and strong on torque. It is quite a bit lighter than the 300, will fit better, has more aftermarket support, is a jeep engine, will mate to his drivetrain EASILY, and will not incur the inevitable cooling problems that will result from trying to shoehorn a long 300 into the jeep engine bay. The 300 is a great motor...but if you don't have one and are shopping for a replacement motor, swapping in the 4.0 is a better idea.

good point, but a good scrounging session might locate one attatched to a NP435. Appropriately built, (carb Cam) would get a good powerplant that would probably nevery be fully drawn upon. (My expeience is limited to 258s, but my buddys 33d CJ7 has yet to run out of power)

But yes, length is a problem. but then again. If you want to go ahead and give it a try. I mean how many Jeeps have had Chev 350s and ford 351s put into them, I honestly think a GM 250 (or 292) hooked to a SM465 would be great and likewise the 300.
Im currently brainstorming with a couple of buddys on how to install an Air colled 3cyl Deutz Diesel into a SWB Jeep.
Whatever trips your trigger.

Jesse

Just a side note, but GM is going to be offereing an inline 6 again! Hmmmmm.....seems the boys at GM have have rediscovered torque!

Yes, finally, a new inline 6. I've just finished installing a 69 250 chevy 6 in my 86 truck. I've gone through the whole thing, and made it better than new. Also topped it off with fuel injection. The low RPM torque was what I'm after, not HP or speed. The new 6, however, is quite different. The only thing similar to the 6's of past is that there are 6-cylinders all in a row. They've thrown a lot of new technology and new ideas into it. It'll be interesting to see some reviews of it's perofrmance.