early 232 head vs. 4.0L H.O.

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   I have read in a couple of places that the early 64-67 or so  232 heads flow very well compared to the later 232-258 heads. Supposedly, the chambers are smaller too. I recently pulled one of these heads and found that the intake ports are huge. Some have even suggested that the early 232 head will provide comparable performance to the 4.0 head in a swap situation.

I recognize that there is the shaft rocker situation. But has anyone seen, heard, or experienced any truth to this?

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RamblinMan Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/26/2007 Location: Port Charlotte Status: Offline Points: 1237	Post Options Post Reply Quote RamblinMan Report Post Thanks(0) Quote Reply Topic: early 232 head vs. 4.0L H.O. Posted: Sep/26/2007 at 7:40am
	I have read in a couple of places that the early 64-67 or so 232 heads flow very well compared to the later 232-258 heads. Supposedly, the chambers are smaller too. I recently pulled one of these heads and found that the intake ports are huge. Some have even suggested that the early 232 head will provide comparable performance to the 4.0 head in a swap situation. I recognize that there is the shaft rocker situation. But has anyone seen, heard, or experienced any truth to this?

Wrambler Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/02/2007 Location: West Virginia Status: Offline Points: 4199	Post Options Post Reply Quote Wrambler Report Post Thanks(0) Quote Reply Posted: Sep/27/2007 at 1:25pm
	From what I know of this the head looks good, but was designed in the day of bigger is better. It has large ports but the newer heads have better flow do to increased understanding of what is needed to do this. The early head has large ports, small valves, 1.5 shaft rockers. Late head has larger valves smaller ports, but with better flow design and 1.6 ratio paired moutn rockers. You may well be able to get good flow out of the early head. You will need to enlarge the valves and do some port work to clean up the casting. You will still have 1.5 ratio rockers. Lastly, if it is a street car or Jeep where you want torque and low rpm grunt the 4.0L head will win in that dept.
	Wrambler 69 AMC Rambler 4.0L, 5 speed 2015 Grand Cherokee Limited 2019 Chrysler 300

tyrodtom Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Sep/14/2007 Location: Virginia Status: Offline Points: 6214	Post Options Post Reply Quote tyrodtom Report Post Thanks(0) Quote Reply Posted: Sep/28/2007 at 12:01am
	The early shaft rocker engines had a cam with more lift and duration than the late pedestal rocker engines. .254 verses .248, duration in. 259, ex.289, verses 256 en. and ex. I put the stock cam from a early shaft rocker engine in a 74 232 and woke it up somewhat, but I could never get it to produce the power of my 69 232, offy,390 Holley, header engine. Even with the same external changes. I think for street use the 4.0 head would probably be the better combination, and my next car will have it. But for higher rpm use I bet a early shaft rocker head with large valves and some port work would make better power, but it wouldn't be cheap. Edited by tyrodtom - Sep/28/2007 at 12:07am
	66 American SW, 66 American 2dr, 82 J10, 70 Hornet, Pound, Va.

Wrambler Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/02/2007 Location: West Virginia Status: Offline Points: 4199	Post Options Post Reply Quote Wrambler Report Post Thanks(0) Quote Reply Posted: Sep/28/2007 at 2:53am
	Comparing the early big port head to the later 70's-80's small port head is no contest. The big port head wins hands down. Especially when equipped with large valves and reworked. The 4.0L head excells in providing a clean powerband through out the designed power band up to 5200 rpm. Drag racers, have achieved realy excellent results with the 4.0L heads by enlarging valves and with port work. I would work with the 4.0L head simply because in street use it needs next to nothing done, bowl cleanup, mild polish, valve sizes are fine. If you want more you can add larger valves, same as the early head. I also would not condemn anyone from using a large port head as, to each his own... For a direct bolt on swap head, my choice is 4.0L. I have a 69 big port head if anyone wants one. Not closed chamber though. stock 75K on it.
	Wrambler 69 AMC Rambler 4.0L, 5 speed 2015 Grand Cherokee Limited 2019 Chrysler 300

farna Members Profile Send Private Message Find Members Posts Add to Buddy List Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19692	Post Options Post Reply Quote farna Report Post Thanks(0) Quote Reply Posted: Sep/30/2007 at 7:13am
	Chris Morrison in/around Kansas City used to run a highly modified early big port head on his drag Javelin. I told him the 4.0L head would be better, and he finally changed a couple years ago! I don't recall what kind of increase in performance he got, but he definitely liked it. He was reluctant to change at first (I told him about this... well, MANY years ago) because of all the work he had in the shaft rocker head. See http://members.tripod.com/~Mojo_Page/Rokr1.htm to see what I mean! He hasn't updated the pages in several years, but still lots of good info on there. On the head casting # page he mentions that the 4.0L head has better flow potential even though the exhaust ports are very small compared to the early head.
	Frank Swygert