Mopar P4532900 head info needed

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I would too. I’ve seen 435 Hp at 5100 475 torque at 4400 and it makes over 400ft. Lbs From 2500 -5700. These are quoted from the ‘how to build big-inch mopar small blocks‘ book by Jim Szilagyi. He worked for mopar for many years in many performance capacities so it’s probably accurate.
I’m sure it is. I’m going to have to look that engine up and re read it’s specs.
 
I’m sure it is. I’m going to have to look that engine up and re read it’s specs.
I’ve been trying to find info on it too, and there’s not much out there.
best I can make out from bits and pieces here and there is: 9.0:1 compression with KB hyper U piston, eagle rods, cast stroker crank 4”. Cam, roller, I guess is .501 in .513 ex with 230/234 and I believe 108. It’s lumpy sounding. Oh yah, and the magnum R/T heads.

I don’t think there are many out there as they were introduced and then discontinued not too long after that with the advent of the Hemi and all..

if you find good info let me know!
 
Hopefully, this weekend, if all things line up, I’ll have flow numbers from a stock OEM Magnum head. It would be on a local bench. So numbers between the reports are to be taken with a grain of salt.
I was under the impression that stock OE magnum heads would flow 210 on intake@550
 
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Is that the head with the exhaust ports that don’t match anyone’s previous header flange? Or extremely close to not matching up?
I remember those. I think they were the LA aluminum Commando heads. The exhaust ports looked like AMC.
 
You talked about running a bigger valve. Not sure if it is just my eyes, but those valves look like they are almost touching.
 
I’ll be flow testing Magnum heads Saturday.
There's Magnum flow numbers all over the place I think the ones I flowed.. only flowed like 209 CFM @28"
The chambers are restrictive to low/mid lift flow. I have a set of 2/1.59 valve speed crapper mags for jimmer that do far better and they aren't even "worked" to that extent.
 
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There's Magnum phone numbers all over the place I think the ones I flowed.. only flowed like 209 CFM @28"
The chambers are restrictive to low/mid lift flow. I have a set of 2/1.59 valve speed crapper mags for jimmer that do far better and they aren't even "worked" to that extent.
Thanks! Charlie never had a set on his bench. So he invited the heads to it. We’ll also bolt on a Chink AG and a carb to see what happens.

I’ll be using the OEM Magnum head on a 5.9 and a small Howard’s Hyd cam @ 220@050. The other 5.9 is making use of an old Crane Hyd cam @ 236@050. I’m just screwing some crap together on a temp basis for fun until the LA’s are done.
 
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Thanks! Charlie never had a set on his bench. So he invited the heads to it. We’ll also bolt on a Chink AG and a carb to see what happens.

I’ll be using the OEM Magnum head on a 5.9 and a small Howard’s Hyd cam @ 220@050. The other 5.9 is making use of an old Crane Hyd cam @ 236@050. I’m just screwing some crap together on a temp basis for fun until the LA’s are done.
Better low mid numbers than the j heads on about every flow bench in existence...but the j heads peak a hair higher. It's no mystery. 150cc vs 160cc.
Charlie is Ford's but he found a bigger audience with the 273 318 crowd. If you're the one holding the camera, aim it at the flow com so we can see the numbers and not at the had an intake bolted to it. LOL
 
I’ll try, limited space, very tight.

Charlie is a Chevy guy and owner but his recent upswing in the MoPar crowd was due to DV and the mission impossible project. News spreads fast in the smaller MoPar community.

I’m pretty sure he doesn’t care what head he ports and flows.
 
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Better low mid numbers than the j heads on about every flow bench in existence...but the j heads peak a hair higher. It's no mystery. 150cc vs 160cc.
Charlie is Ford's but he found a bigger audience with the 273 318 crowd. If you're the one holding the camera, aim it at the flow com so we can see the numbers and not at the had an intake bolted to it. LOL
He’s writing down what we see. Why is it important? Or just curious?
 
Ok my buddy came out today so I could check a head out and can now update a little. They have 5/16 (2.02) intake valves and 1.650 exhaust valves. Looks like kinda piss poor 2 angle valve job with throat kinda “roughed” in but I didn’t measure it. They may be getting a valve job later. As you can see in the pictures above the pushrod holes were tubed. That common wall angles in big time so I test fit a piece of 9/16 brass tube that I drill my Speedmaster and Edelbrock heads for and it slide in perfectly. He may epoxy some in and push that wall over. I’m not going to mention the business that ported these but I think I did above. To send heads out like this is a sin. The valve job is sunk in the chamber real bad. So my buddy is planning on laying that back some and straightening out the wall. I told him I’ll blend the short turn into the straightened wall for him. I need you guys to look at these exhaust pictures. Someone marked the blueing out like a standard LA exhaust but stopped short. I think I forgot to mention above these are magnum heads so magnum rockers, magnum oiling. Someone above mentioned that they thought they use a different exhaust pattern but my Edelbrock LA exhaust bolt holes lined up perfectly.

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ok. it took me a while to find it but I had a FB post saved about these heads. supposedly KG engines in Kansas, Ohio has a CNC program for these heads. 419-806-5870, 419-986-5117, 1-866-986-5115.
 
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