I have an 83 CJ7 and I was wondering what motor would better suit it. I want a lopey idle.. like the top fuel dragsters.. and want adequate torque to wheel... but then again..jeeps have to be pretty light, as I've seen that 6.0l powerstroke jeep on the dunes and it didnt fair so well.. I want reliability as well, yet not SO much power that I crack the frame... because Im told its not nearly as strong as the Yj's and well lets face it, its almost 30 years old!
It's easier to de-tune a 351, than it is to hot rod a 302. I'd build a 351 and never look back.
Back in the day, the Cleveland was the better motor, but today I'm hearing that the windsor engines are what's going in most of the Cobras. Maybe it is just because it is too hard/expensive to get a cleveland IDK.
'85 CJ7, BDS 4" lift, 1" Body lift, 33x12.5, Shrockworks Sliders, 304 V8 with RV cam., T-176, D300, Dana 30, AMC 20. 1986 CJ10-A SD-33 Diesel/727/np208 1971 800B with 345/T-19
06' TJ Rubicon, 4" R.C. springs, BFG/AT 35s M.C. 6" fenders, rockers and surrounds, Currie front & rear adj. tracbars, tattons DC rear shaft, adj. upper - lower CA's. Bilstein 5100's YJ Buggy Build Current project. Stroker/FI ?
1990 MJ Comanche 4.0L AX15/np231
You won't want that lopey idle when trying to maneuver over an obstacle. Those cams are that way because they are designed for high RPM power. They have nothing to offer in the lower RPM ranges, where your Jeep would be spending most of it's time on trails.
As for 351w or 302, the 351 has more cubes, so it will have more output from the start. If you want to build something with power, go the 351w. Just remember that the bottom half externally is the same as a 302, but the top is wider, so clearance is gonna be a little tighter for the steering shaft to headers and such. The advantage is that 302 motor mounts and such should fit it in there. You will also have to find a oil pan that fits, I think the one from the cars are needed, and there weren't many 351w cars, so an aftermarket pan for a mustang swap or something may be required.
1978 CJ5 5.0HO/T177/D300, '86 D30/D44 WT axles, 'glass body, 31x10.5 BFG A/T, TDK galv'd frame - DD and weekend toy
My friend had a hopped up 289 in his Bronco that just plain ripped. He swapped that out for a FI 302 and it still gets around pretty good. Mine doesn't seem anemic to me either. Sure if I had 38's with 2.73's but that is hardly the engines fault. The year of the engine and the compression ratio will also make a difference.
Mike My build thread
1979 CJ7, FI 5.0L Ford, NP435, D300, Full floated D44 Detroit, D30 Detroit EZ Locker.
A 302 can be made to be pretty beastly. It really depends on what is done to it. A stock 302 from late 80's early 90's is pretty pitiful though. A 351 isn't much better, but is not bad. Cousin has a 351 bronco with 33's and T18. 3.73 gears. My 258 jeep with t18 and 3.55 will run with it.
Put a little head work and you could have a strong engine. Or get an older, pre '70 351w and you've really got something there.
Allot depends on what you plan to use your Jeep for as to which engine would be better. If you want a dependable daily driver that isn't going to break you on fule then the 302 can't be beat. It's also ligther than the 258 you now have and the 351 too. If you rub the 302 you need to make a decision, now. The 302 is well noted for being a quick revving engine. The ones Ford used in the later Mustangs that are fuel injected are easily modified to make 300 hp. A stock 302 has less than desirable heads. That can easily be changed.
The 351, in my opinion, is somewhat of a neglected engine. It's longer stroke makes better torque than the 302, which is good for slow speed crawling. It is heavier than the 302 though. Also as noted a bit bigger.
Either engine would make a good swap for you but you're going to have to decide what you want to use it for and build accordingly. As Cutlass327 said the rough idle cam won't be much good.
if you can find a 5.0l explorer motor its a great cheap motor get a nice low end torque cam, valve springs and some rockers and you have a 260/315 hp/tq engine. If you ever want more power/break there are a ton of cheap parts for the 302 compared to the 351. Intakes are abundant for the 302.
as for a hopped up 302 in the one post being pitiful, im curious as to the specs.
Don't do business with Tuff Designs, worst retailer ever.
I put the Holley Systemmax intake on my Mustang and that really woke it up. That's for a fuelie set up though. If you search Craigslist. Look for Mustang parts if you decide to go with a 302. You could probably find a set of heads and a intake or carb for a reasonable price.