Full Size Jeep Network

I recently acquired a 258 engine, however need some help with identifying it. Trying to figure out what year it came from, and if there will be any issues with it going into an 80's FSJ (or possibly a scrambler I'm building). The last digit on the block casting number is 5.

Thanks in advance.

pyro wrote: ↑Mon Mar 30, 2020 10:09 am I recently acquired a 258 engine, however need some help with identifying it. Trying to figure out what year it came from, and if there will be any issues with it going into an 80's FSJ (or possibly a scrambler I'm building). The last digit on the block casting number is 5.

Thanks in advance.

Did you look at the TSM?

I'd guess 1974-5. EGR, no air pump.
Revised - it's a later year, like '76-78 - air pump bracket is there. Looks like a YF which was gone by '79. Definitely '80 or earlier.

Definitely a 70's engine. Tgreese's post above should help you figure out the exact year. But he is most likely spot on as it being a 74-75.

So it should have the heavier crank (80.5+ had fewer counter weights). The block is also a bit heavier, and larger head bolts. Intake and exhaust are garbage though. But the 80+ aluminum setup bolts on, or there is after market options.

Let me get a look at it tomorrow and I'll see if I can find that number. Guy said the bell housing came from a t176, ill have to see if that's right. Any benefit to putting this one in my 82 cherokee vs keeping the one that was in it originally for a reman?

pyro wrote: ↑Mon Mar 30, 2020 9:34 pm Let me get a look at it tomorrow and I'll see if I can find that number. Guy said the bell housing came from a t176, ill have to see if that's right. Any benefit to putting this one in my 82 cherokee vs keeping the one that was in it originally for a reman?

There is some debate as to which version of the engine is better. Heavier crank means more inertia, so harder to stall. The lighter one revs faster and higher. The later intake and exhaust is hands down better, and can be put on the older engine.

The one thing I am not sure on is accessory brackets and mounts.

I have the later manifolds on my '77. The only issue was interference between the steering pump bracket and the newer exhaust manifold. A small notch in the bracket solved that.

Found that plate. It says
" A
203 11"

Do you need help to interpret that?

1976=9, 1977=1, 1978=2. March 11, 1978. 258 1V. It's got to be from a CJ or car, because the FSJ 258 got the 2V BBD starting 1977.

Haha no I figured it out, sorry. The guy had a few CJ's and I initially got it for parts, but started to get curious about the differences. Thanks for the help.