232 vs 258

MaxW

I am new to these 6 cylinders and would like to know what the differences are and what is interchangeable. Also can a normal AMC T-10 and bellhousing go behind them? Any help or direction would be apprecitated. Thanks Adam

Mudrat

tarra wrote
I am new to these 6 cylinders and would like to know what the differences are and what is interchangeable.

Also can a normal AMC T-10 and bellhousing go behind them?

Any help or direction would be apprecitated.

Thanks
Adam

Hi Adam, and welcome to the world of straight 6's :t: Just remember we get no respect, and about as many custom parts :roll:

Most everything in the 232 and 258 are the same and share the bell housing pattern. Bore is the same at 3.75, but the stroke is different (crank) 3.50 on the 232 and 3.90 on the 4.2L. Compression is a point lower too because of that ... 8.5 vs 9.5 in the 4.2. I've heard the deck hight is a bit different, but can't confirm that anywhere. But swap them cranks, keep the rods and you should be golden :wink:
And if it's any consolation, we have a local ball player (for the Tides) that is having my local hot-rod shop put a blower on a 232 :shock: So some neat parts can be had $$$

Not familiar with the T-10 though? :-|
pat

Lifted79CJ7

Mudrat wrote
And if it's any consolation, we have a local ball player (for the Tides) that is having my local hot-rod shop put a blower on a 232 :shock: So some neat parts can be had $$$

Ohhhhh!! Take pics and get specs for us! What's he putting it in?

Mudrat

Lifted79CJ7 wrote
Ohhhhh!! Take pics and get specs for us! What's he putting it in?

Have no clue what it's going in, but it was his dads car that became his first car. The rebuild was around 2 grand the blower is another 2200 :shock: Hope the car is worth it :roll:

junkyard jim

Lil bit of AMC 6 info. After the 196 (flathead and OHV, made from the same block) went away (early '60s) AMC made the 199 and 232. In '71, AMC raised all their blocks (V8 and 6) and the 199 became the new 232 (Cu inch is the same by fluke. Bore/stroke are different as well as crank, rods and pistons), 232 became the 258 (71 was a year by itself. It's the only one with the early 6 bolt pattern housing) In '72, all the 6 cyls were changed to the V8 pattern to cut down costs (also the 258 was tearing up the lighter bells and needed a bigger flywheel and clutch) The '72 up 232, 258 (became 4.2L in '80 with some internal changes that lightened the motor a lot) and 4.0L all share the same bellhousing pattern. 232 went away @'80 (definitely by '83 along with all AMC cars except the Eagle which went away in '88 model year when Chrysler took over and sold the name) 4.2L went away in '91 and 4.0L just this past year except in Rubicon TJs. There are lots of parts that can interchange (and some that won't) I'm currently swapping a 4.2L with a 4.0L from a '93 Grand Cherokee (and having to move at the same time!) There were a number of transmissions used with the 6 too. FSJs got T18A (6:1 first gear), T18 (4:1 first gear), T176 ('79 up 6 cyl), 999 (904 based), 727 and T5 '80 to '83 pickups only. XJ, MJs and some YJ/TJs got a variety: rare T5, AX-15 (suggested as best factory trans), BA 10/5 (okay for a daily driver not driven too hard), AW4 automatic. I think that covers them all.