The AMC Forum : 232 upgrade to 258? http://theamcforum.com/forum/ This is an XML content feed of; The AMC Forum : 6 Cylinder Engine Repair and Modifications : 232 upgrade to 258? Tue, 18 Jun 2013 01:59:34 +0000 Sat, 09 Jun 2012 09:51:43 +0000 http://blogs.law.harvard.edu/tech/rss Web Wiz Forums 10.03 360 theamcforum.com/forum/RSS_post_feed.asp?TID=40255 The AMC Forum http://theamcforum.com/forum/http://www.theamcforum.com/forum/skin_images_amc/forumheader.png http://theamcforum.com/forum/ 232 upgrade to 258? : farna wrote:Why the 258 sump?... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367195.html#367195 Author: Wizzle
Subject: 40255
Posted: Jun/09/2012 at 9:51am

Originally posted by farna farna wrote:

Why the 258 sump? Economics. Same sump bolted to the 232 and 258, why make two different ones? The bumps on the left side do noting in the 232, but do no harm either. That's why I questioned the two intakes, but AMC may have used two different suppliers anyway, or they made enough manual steering cars that the 3-5 cents of aluminum for the PS mounts made a difference to the bean counters... or maybe the engineers just didn't like the looks of bosses sticking out on the intake with nothing attached. The sump doesn't easily show like the intake does.

The only way to determine if you have a 258 is to measure the stroke. Get a piece of stiff wire and run it in a spark plug hole. Run the piston down to the bottom then mark the wire. Run piston to top and mark again. Make sure you use the same reference point when marking. Measure between marks. Is it closer to 3.5" or closer to 3.895"? Shorter is 232. Your measurement should be slightly more than the actual stroke due to the angle. If the measurement is anything less than 3.895" it's a 232. The 258 will measure right at or over 4" using this method.

You are correct, pre 1979 casting numbers are shared between the 232 and 259. I found one  casting number in my list that is in the 232 section that isn't in the 258, but that is likely a mistake -- it is probably a 70 only number, or should be in the 258 listing also. I have it listed as 70-72, bit it can't be over that range since the 71 block is taller. But then some of the short blocks were likely still cast for a couple years to allow for warranty replacements. If a block cracked or was otherwise damaged in a new enough car the internal parts would be changed over. Makes no monetary sense now, but back then the dealer and/or factory probably saved a bit by doing it that way. Labor costs in the US have skyrocketed until it's not worth the effort any more, that tells you something about how labor costs have gone up right there!


No worries. I ended up going through that exact procedure not long after posting the question and it measures pretty close to 3.5". Dammit. That would have been a great surprise!
]]> Sat, 09 Jun 2012 09:51:43 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367195.html#367195 232 upgrade to 258? : Why the 258 sump? Economics. Same... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367181.html#367181 Author: farna
Subject: 40255
Posted: Jun/09/2012 at 8:55am

Why the 258 sump? Economics. Same sump bolted to the 232 and 258, why make two different ones? The bumps on the left side do noting in the 232, but do no harm either. That's why I questioned the two intakes, but AMC may have used two different suppliers anyway, or they made enough manual steering cars that the 3-5 cents of aluminum for the PS mounts made a difference to the bean counters... or maybe the engineers just didn't like the looks of bosses sticking out on the intake with nothing attached. The sump doesn't easily show like the intake does.

The only way to determine if you have a 258 is to measure the stroke. Get a piece of stiff wire and run it in a spark plug hole. Run the piston down to the bottom then mark the wire. Run piston to top and mark again. Make sure you use the same reference point when marking. Measure between marks. Is it closer to 3.5" or closer to 3.895"? Shorter is 232. Your measurement should be slightly more than the actual stroke due to the angle. If the measurement is anything less than 3.895" it's a 232. The 258 will measure right at or over 4" using this method.

You are correct, pre 1979 casting numbers are shared between the 232 and 259. I found one  casting number in my list that is in the 232 section that isn't in the 258, but that is likely a mistake -- it is probably a 70 only number, or should be in the 258 listing also. I have it listed as 70-72, bit it can't be over that range since the 71 block is taller. But then some of the short blocks were likely still cast for a couple years to allow for warranty replacements. If a block cracked or was otherwise damaged in a new enough car the internal parts would be changed over. Makes no monetary sense now, but back then the dealer and/or factory probably saved a bit by doing it that way. Labor costs in the US have skyrocketed until it's not worth the effort any more, that tells you something about how labor costs have gone up right there!

]]> Sat, 09 Jun 2012 08:55:34 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367181.html#367181 232 upgrade to 258? : farna wrote:So I guess there... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367163.html#367163 Author: Wizzle
Subject: 40255
Posted: Jun/09/2012 at 2:54am

Originally posted by farna farna wrote:

So I guess there was at least two different intakes. I sure wouldn't have made two!

Yes, the Jeep oil pans are deeper, so you'd need the pickup tube as well. He'll also need a 258 oil pan... maybe.

Wizzle, look on the left side of the oil pan where it's close to the block. Is the pan smooth, or are there some "bumps" along the side of the pan? The "bumps" are there to clear the 258 rods. I believe AMC made only one pan, but that may have only been for the last few years of the 232.  If you have the "bumps" in your pan you can use the pickup tube and pan from your engine. If not, you might be able to dent the pan with a hammer to clear the rods rather than ship one over. A 4.0L pan and pickup tube will work to, I think. Those you can find over there.

Hi Frank, thanks again for the feedback. My engine is currently configured with a non-standard 2-barrel intake and carb, alternator on the LHS, after-market power steering with the pump on the RHS, and the sump does have the 3 'bumps' on the LHS (this was a bit of a surprise).

Here's a question I didn't think I would be asking...
How do I know if I already have a 258 under the hood (either original or upgraded from an original 232)?

I had never actually considered that as a possibility. I know the Jeep has undergone some serious mods before I owned it. I think it may have actually been pieced together from two vehicles (a bit of a '74/'75 hybrid). The body tub seems to be from a '75, but the VIN says it's a '74 with a 232.

Given the block is the same on both the 232 and 258, the engine casting number (3218618) would be the same on both - wouldn't it?

Given the sump seems to be from a 258, the question is - Why would it have this sump fitted?
Is it possible it has already been upgraded to a 258?

can the stroke be measured through a spark plug hole?

I'm more confused than when I first posted on the forum!


]]> Sat, 09 Jun 2012 02:54:55 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367163.html#367163 232 upgrade to 258? : What about a 4.0L from an XJ? ... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367041.html#367041 Author: carnuck
Subject: 40255
Posted: Jun/08/2012 at 4:15pm

What about a 4.0L from an XJ?]]> Fri, 08 Jun 2012 16:15:02 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post367041.html#367041 232 upgrade to 258? : If you use a oil pan that... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366819.html#366819 Author: tyrodtom
Subject: 40255
Posted: Jun/07/2012 at 7:09pm

  If you use a oil pan that came from a Jeep in a car,  in most cars, it is gonna drag.
 
  The sumps are deeper on the Jeep oil pans i've seen.  I had to use the oil pan and pickup from my 77 Gremlin,  to keep the 4.0 pan from being too low on my 66 American.


Edited by tyrodtom - Jun/07/2012 at 7:10pm]]> Thu, 07 Jun 2012 19:09:44 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366819.html#366819 232 upgrade to 258? : So I guess there was at least... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366816.html#366816 Author: farna
Subject: 40255
Posted: Jun/07/2012 at 6:41pm

So I guess there was at least two different intakes. I sure wouldn't have made two!

Yes, the Jeep oil pans are deeper, so you'd need the pickup tube as well. He'll also need a 258 oil pan... maybe.

Wizzle, look on the left side of the oil pan where it's close to the block. Is the pan smooth, or are there some "bumps" along the side of the pan? The "bumps" are there to clear the 258 rods. I believe AMC made only one pan, but that may have only been for the last few years of the 232.  If you have the "bumps" in your pan you can use the pickup tube and pan from your engine. If not, you might be able to dent the pan with a hammer to clear the rods rather than ship one over. A 4.0L pan and pickup tube will work to, I think. Those you can find over there.
]]> Thu, 07 Jun 2012 18:41:15 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366816.html#366816 232 upgrade to 258? : farna wrote:PS shouldn't... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366781.html#366781 Author: Hornet_Tom
Subject: 40255
Posted: Jun/07/2012 at 2:56pm

Originally posted by farna farna wrote:

PS shouldn't be a problem. Most cars and Jeeps used it, and I believe all the intakes have the bosses for the brackets. RHD cars should just have longer hoses with the PS pump still on the left side. There was a change in where and how the pump mounted, but I think that all the 74+ 258s mount the pump the same. 72-73 258s use a different timing cover and accessory mounts, but you can make the older ones work with a little effort (not much).

Check the AMC clubs in Australia. Remember, a 258 from an AMC car will work just as good as one from a Jeep. Wranglers had the 258 up to 1989 as well, not just CJs. I don't think they sold many of the full size Jeep trucks down there, is any. 
Frank, I have a 1974 Hornet with a 232 and no power steering that does not have the PS bracket boss on the intake manifold.  I was planning to convert it to PS when I ran into that inconvenience. I will deal with it later whenever I update the intake and possibly the head.
 
 
]]> Thu, 07 Jun 2012 14:56:28 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366781.html#366781 232 upgrade to 258? : farna wrote:Check the AMC clubs... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366765.html#366765 Author: KermitDRambler
Subject: 40255
Posted: Jun/07/2012 at 1:05pm

Originally posted by farna farna wrote:

Check the AMC clubs in Australia. Remember, a 258 from an AMC car will work just as good as one from a Jeep. Wranglers had the 258 up to 1989 as well, not just CJs. I don't think they sold many of the full size Jeep trucks down there, is any. 
 
Isn't the oil pan and pickup tube different on a Jeep? Not a big deal to switch if it is but it's something to pay attention to.
 
Matt
]]> Thu, 07 Jun 2012 13:05:51 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366765.html#366765 232 upgrade to 258? : PS shouldn't be a problem.... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366732.html#366732 Author: farna
Subject: 40255
Posted: Jun/07/2012 at 7:46am

PS shouldn't be a problem. Most cars and Jeeps used it, and I believe all the intakes have the bosses for the brackets. RHD cars should just have longer hoses with the PS pump still on the left side. There was a change in where and how the pump mounted, but I think that all the 74+ 258s mount the pump the same. 72-73 258s use a different timing cover and accessory mounts, but you can make the older ones work with a little effort (not much).

Check the AMC clubs in Australia. Remember, a 258 from an AMC car will work just as good as one from a Jeep. Wranglers had the 258 up to 1989 as well, not just CJs. I don't think they sold many of the full size Jeep trucks down there, is any. ]]> Thu, 07 Jun 2012 07:46:48 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366732.html#366732 232 upgrade to 258? : billd wrote:Being that's... http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366723.html#366723 Author: Wizzle
Subject: 40255
Posted: Jun/07/2012 at 2:36am

Originally posted by billd billd wrote:

Being that's a 74 Jeep, I"m with the fellow from Texas - a 258 would be a drop-in.
no modifications, mounts and bell housing would be in the right places.
Sometimes you need to watch for power steering bracket mounting - I've seen intakes with different holes and placements, but can't recall the details. but that's a simple thing.
Yep, he said it well.

Cheers Bill.
I'll begin the hunt (locally) for a complete 258 then...
Failing that, I'll start to look further abroad (US) for the components to upgrade.
Do you mean the power steering pump bracket? Was power steering standard on all 258 equipped vehicles? I eventually had to upgrade to power steering after finding it too difficult to source manual steering parts for a right hand drive. The RH manual steering boxes seem to be as rare as hen's teeth.
]]> Thu, 07 Jun 2012 02:36:22 +0000 http://theamcforum.com/forum/232-upgrade-to-258_topic40255_post366723.html#366723