258 to small for a swap?

[blthomas]

I've been searching, reading and trying to absorb whatever I could from this site.

Have a potential trade lined up for a 68' M715 for one of my CJ's.

18k on the 230, rest of truck is very nice (stock).

I have a 258, accessories, header, intake, etc. I also have a AX15, adaptor for D300, and a D300 case.

Thinking I'll find some CUCV axles and start the project.

My question is to you guys knowing these bigger trucks (all I have is CJ's and a TJ), would the 258 with a header and good 2bbl carb, hot ignition, run this thing down the road with the 4.56 and say some 36" swampers?

Thanks for any thoughts or advise. Off to read some more.

Blair

[Barrman]

Sure, it will work. Just don't expect much better performance than the stock 230. This is still a 7000 plus pound truck.

Don't expect anything to mount up directly either. You will need to make all your mounts.


If your plan is off road and highway driving below 60 mph, I think a straight 6 is a great choice.

[jeeper]

First off...Welcome.

Is there something wrong with the 230 that's in it?

I've had a few 258's. They are fine engines but I wouldn't put one in my M715.

I had a 258 with 30,000 miles on it sitting in my barn when I started my swap. I just couldn't muster up the courage to spend the money and energy to put it in because I was too worried about performance long term.

It's about 210 pd/ft of torque but only about 115 hp stock. It's more cost effective to spend the money building a small block chevy. It's probably about the same amount of work to swap in a chevy as it would be to swap in a 258.

[randyscycle]

I have a nearly stock truck that has either a 230 or 250 Chevy inline six in it. (It was in there when I got it, so I don't know which one it is.) It has an SM465 transmission and its otherwise stock. I haven't driven it on the highway much, but a few miles down the road and it does OK. No powerhouse, but it definitely will move along as good as a stock truck.

[Flingarrows]

I rebuilt the 258 that I had in my 83 CJ, and it pepped it up nicely. It had a motorcraft 2bbl, HEI, and 3.31 gears. That said, I agree with the others. It will work fine, probably better longevity than the original, but will not be a power house

[blthomas]

Thanks for the input. The 230 is smoking and not holding good compression. Figure it needs a rebuild after sitting so much at the VFD it used to be home to before the previous owner got it.

That said, sounds like I need to check into a v8 swap. Have lots of Ford stuff laying around, but lots of threads have CHevy swap info.

I can handle fabbing mounts and the like.

Anyone dropped a 460 in? I have 2 of those here holding down the concrete......

[Barrman]

Several 460 swaps have been done. Pretty much if you name an engine, it has been put into a M715. Chevy has been popular because they are so plentiful and cheap.

[Alaska hunter]

if you h ave a bunch of ford stuff laying around a 300 six is a great motor

[Ronner]

The 300 6 is a great option with a 5 speed trans.

That being said, you can drop in a 460 without changing the frame horns - just use 390 mounts and a little patience and it drops right in Add the tranny of your choice and a new stub shaft and you are ready to go.

[Tanner]

Or go with a Chevy C50-C70 series bellhousing, mount a small-block Chevy gasser motor, or a 6.2/6.5 diesel, and use a Spicer 3053A Deuce transmission. Nice overdrive transmission; strong like bull...

'Tanner'
North Carolina