Junkyard 5.9L Magnum + Edelbrock LA heads build

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MopaR&D

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I figure it's as good a time as any to start a build thread for my SBM... The story starts back in February of last year (2017), the 360 in my '70 Duster gave up the ghost (story in itself) and the car has been sitting engine-less since then. I initially thought of doing a full rebuild on the original 318 but for the money it didn't seem worth it. Then I got the idea to pull a 5.9L Magnum from the junkyard so this past March I drove over to the local pull-n-pay yard and ripped one out of a 2001 Ram 1500... it was around $130 for the whole short block including lifters but the 8+ hours spent wrestling the engine out of the truck made it not feel like so much of a bargain LOL. Regardless I'm pretty happy with what I got...

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I pulled the #2 and #4 main bearing caps to install the special main bolts with the threaded holes for mounting a windage tray which I'm reusing from my old 360. Bearings look pretty good, still haven't gotten around to checking the rod bearings though. Also installed the semi-used (25k miles tops) oil pump and car-pan pickup from my old 360.

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I wanted to do something different with the color scheme so I decided on Mopar Turquoise like the non-HP big blocks were painted from the factory (the pics make it look a lot more blue). I just think it's a cool color and you don't see it much.

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Cool build I love magnum engines. I'm following! Love the color btw! Can I ask why your not using the heads? What are you gonna do with the original heads? And what are your plans for induction and cam?
 
Cool build I love magnum engines. I'm following! Love the color btw! Can I ask why your not using the heads? What are you gonna do with the original heads? And what are your plans for induction and cam?

I'm getting to that lol, it's kind of a long story... my old 360 had stock Magnum heads but they need a valve seat job and guide inserts before they're fit to work on another engine. Stock Magnum heads you get from the junkyard are almost always cracked and I already had a pair so I left them in the bed of the truck at the yard lol. Initially I planned to buy a pair of EngineQuest replacement iron Magnum heads and use those but then these open-chamber Edelbrock RPMs popped up on FB marketplace for a good price. I impulsively bought them before I realized they were LA heads and wouldn't get any rocker oiling from the Magnum block but trying to re-sell them was a waste of time so now I'm going all the way. Initial mockup showed they'll need to be milled on the intake side since they will definitely be milled at least .010" on the deck side for cleanup and straightening and the intake holes barely lined up as-is. The Edelbrocks are currently at the machine shop getting worked on and I don't know what the chamber volume comes out to but I doubt it's less than 63cc. With stock Magnum pistons down .050" in the hole and a .027" thick gasket (Cometic MLS) compression will come out to about 9.2:1. The Edelbrocks also came with a full head stud set, it's kind of begging to get a little boost heh heh...

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The cam will be a custom grind from Racer Brown, after talking with Jim over the phone and email he decided on the following specs:
Intake 222* @ .050", .546" lift; Exhaust 226* @ .050", .542" lift; 110* LSA and 106* intake centerline.

Induction will be a non-Air-Gap Performer RPM and 750 cfm Street Demon carb. Also using Hedman 1-5/8" shorty headers into 2.5" dual exhaust, I'm going to try painting them white for more of an old-school look. Also thinking about painting the heads the same color as the block, I don't want the entire top end to be raw aluminum.
 
How are you planning to oil the heads?

So far the plan is to drill a passage in each head from the rear-most rocker shaft pedestal down to the threaded hole normally used for mounting front accessories, then I can tee off the oil pressure sending port and have external lines to the back of the heads. It'll be a trial-and-error deal most likely, I'll probably need to experiment with restrictors to make sure the right amount of oil gets up there.

Alternatives would be drilling the factory passage down to the cam bearings (sounds like a nightmare) or drilling and tapping somewhere inside the valley (lifter gallery?) for oil feed. I kind of like the idea of having the oil supply on the outside of the engine because it would be easier to detect a leak...?
 
I know there is alot of magnum head on la conversions but iv never seen it the other way!! This is gonna be a good. Yea as soon as I saw the title i was chanting Boost boost boost! Haha:steering:
 
To oil the rockers are you going to run a line from the lifter galley to the rocker arm pedestal that feeds the rocker shaft?
 
To oil the rockers are you going to run a line from the lifter galley to the rocker arm pedestal that feeds the rocker shaft?
I saw something like that in a mopar muscle mag one time they ran a oil line outside the engine to the top of the engine!
 
The cam will be a custom grind from Racer Brown, after talking with Jim over the phone and email he decided on the following specs:
Intake 222* @ .050", .546" lift; Exhaust 226* @ .050", .542" lift; 110* LSA and 106* intake centerline.
Is this a hyd roller?
 
I figure it's as good a time as any to start a build thread for my SBM... The story starts back in February of last year (2017), the 360 in my '70 Duster gave up the ghost (story in itself) and the car has been sitting engine-less since then. I initially thought of doing a full rebuild on the original 318 but for the money it didn't seem worth it. Then I got the idea to pull a 5.9L Magnum from the junkyard so this past March I drove over to the local pull-n-pay yard and ripped one out of a 2001 Ram 1500... it was around $130 for the whole short block including lifters but the 8+ hours spent wrestling the engine out of the truck made it not feel like so much of a bargain LOL. Regardless I'm pretty happy with what I got...

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Proud of you ,for not over engineering .
 
Jim at Racer Brown can be considered an expert
note the small difference in intake and exhaust duration 222in 226 ex
those shelf cams with 10+ extra degrees of exhaust are for iron manifolds on low exhaust flow pre 85 LA heads
if you do use them use one size smaller intake lobe (and exhaust) to help avoid reversion
 
Is this a hyd roller?

Yup hydraulic roller, the original lifters look great I'm just going to reuse them and run good oil of course (probably Brad Penn). The rockers will be kind of a down-grade for the rest of the setup but for cost reasons I'll initially run stock stamped (non-adjustable) LA pieces. Once the heads are finished I'll mock up the valvetrain and check the geometry for sure, it really could be anywhere lol.

Still up in the air about adjustable rockers but probably want something steel for the longevity...

Also any thoughts on the pushrods possibly hitting the tubes in the heads from the different angle?
 
Yup hydraulic roller, the original lifters look great I'm just going to reuse them and run good oil of course (probably Brad Penn). The rockers will be kind of a down-grade for the rest of the setup but for cost reasons I'll initially run stock stamped (non-adjustable) LA pieces. Once the heads are finished I'll mock up the valvetrain and check the geometry for sure, it really could be anywhere lol.

Still up in the air about adjustable rockers but probably want something steel for the longevity...

Also any thoughts on the pushrods possibly hitting the tubes in the heads from the different angle?
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The 90 360 with the 308 heads and hydraulic roller cam would have used rhe push rod you need with stock rockers.
 
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The 90 360 with the 308 heads and hydraulic roller cam would have used rhe push rod you need with stock rockers.

I know that would be ideal in this situation or even an early Magnum block but I originally planned to used Magnum-based heads anyway. I will be using hollow pushrods as another source of rocker oil btw.
 
Initial mockup showed they'll need to be milled on the intake side since they will definitely be milled at least .010" on the deck side for cleanup and straightening and the intake holes barely lined up as-is. The Edelbrocks are currently at the machine shop getting worked on and I don't know what the chamber volume comes out to but I doubt it's less than 63cc.
It should lose chamber volume at about the same rate as for an open chamber iron head, maybe a touch more... i.e., about 1 cc for each .005 milled off.
 
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The 90 360 with the 308 heads and hydraulic roller cam would have used rhe push rod you need with stock rockers.
UNLESS HE REGRINDS THE CAM
stock rockers should work fine
stiff pushrods stiffer the better
dbl check your springs and if heads are apart machine the guides
new viton stem seals
 
The heads will definitely be getting the valve seats cut, all new valves, guides reamed (they were definitely tight, I'm surprised it ran on the last guy's engine), new springs, valve seals, milling for straightness (then maybe a bit more depending on where the chambers end up) and MAYBE some light porting. When my machinist saw the heads up close he seemed pretty eager to clean up the ports, mentioned it would make a noticeable difference... cost is the only restriction as is typical for most people lol

BTW the machine shop I'm using builds tons of racing engines, they specialize in American performance engines and transmissions (yes they mostly do Chevies but they know and respect Mopars as well). I know the owner pretty well I actually tried working there for about a month as a mechanic but couldn't cut it, I'm way too slow and meticulous lol
 
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Heads are getting worked on now... Included with the Eddy heads was a full set of ARP head studs with hardware (partly what made it more of a good deal for $750) which I'd be dumb not to use. Since I'll have some serious head clamp-age the idea of some day throwing a Procharger or turbo setup with 6-10 lbs. seems more realistic. In that case I'll probably want wider ring gaps, so should I re-ring and do bearings on the bottom end? I don't like fixing something that isn't broke but I've been seeing more mentions of it lately on Magnums so it got me thinking. What brands for both should I look for? I like the full-groove oiling on the mains that's a nice feature and it gets mentioned quite a bit in the old "Mopar bibles" for 360 and 400 engines in particular (why those?)
 
I’d have to re read it but if they mention it specifically for those engines, they share a cast crank as a common denominator.
:rolleyes:
On a heavy hitter, it would be good to do if not any engine.
 
I’d have to re read it but if they mention it specifically for those engines, they share a cast crank as a common denominator.
:rolleyes:
On a heavy hitter, it would be good to do if not any engine.

Good point I didn't think about the cast cranks...

Clevite has these Clevite H-Series Main Bearings MS1266HG looks like what I need. Lots of choices on rings though.
 
I’d have to re read it but if they mention it specifically for those engines, they share a cast crank as a common denominator.
:rolleyes:
On a heavy hitter, it would be good to do if not any engine.
.
Except the 400 4speed crank is forged where the 360 is not.
 
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