Junkyard 5.9L Magnum + Edelbrock LA heads build

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The intake is gonna settle a bunch with torque. Our Edelbrock RPM on Edelbrock heads set up quite a bit and the bolts were tough to all get started, but once we got them in, it all worked its way down. That LA block had been decked about .010", which is not far from your stock Magnum deck height.
 
nm9stheham said:
The intake is gonna settle a bunch with torque. Our Edelbrock RPM on Edelbrock heads set up quite a bit and the bolts were tough to all get started, but once we got them in, it all worked its way down. That LA block had been decked about .010", which is not far from your stock Magnum deck height.
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OK good to know, yeah last thing I need is to wait another 2-3+ weeks for my machine shop to mill the intake down. I've always wondered though, every aftermarket aluminum intake I've put on a Mopar V-8 sat up high and barely had room for the bolts to thread in, is there a reason for that?
 
MOPEkidD-3 said:
OK good to know, yeah last thing I need is to wait another 2-3+ weeks for my machine shop to mill the intake down. I've always wondered though, every aftermarket aluminum intake I've put on a Mopar V-8 sat up high and barely had room for the bolts to thread in, is there a reason for that?
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All I can guess is that is where you want to start, with the bolts just threading in at the bottom of the holes. As it torques down, the holes 'move down' and the bolts get higher in the holes (though you can't see it). If you started with the bolts in the middle or near the upper edges of the holes, then as it torqued down, the bolts might eventually bump into the upper edge of the holes, and then things would not completely settle down.

Seems like this is a matter for any vee-shaped intake interface.....
 
gzig5 said:
Is that the 625 or 750 Street Demon?
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It's the 750, could probably use even more but I'm thinking of saving up for converting to EFI instead. That way it'll already be installed and set up when I go to do my 5.7 Hemi swap.
 
Got the external oiling installed, looks like I could have gone about an inch shorter on both lines...

I'm also going to get a checking pushrod tomorrow to figure out what length pushrods I need. Anyone know what kind of lifter preload I should be aiming for with factory Magnum roller lifters?

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Yes, you could turn the center fitting parallel to the block and adjust the other two according to that...
which means you'd have to shorten the lines some.
Hope I'm not getting punished now for nitpicking... :)
 
I think it is good; a little extra slack keeps the tension off of the ends. See if you can support the longer line.
 
nm9stheham said:
I think it is good; a little extra slack keeps the tension off of the ends. See if you can support the longer line.
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The lines are pretty dang stiff that's why I oriented the fittings that way, I could have straightened the Tee but then the lines would have had to make a tighter bend and the way it sits now there's almost no stress on the fittings or hose ends. I'll see about making a tiny bracket that comes off the farthest-back intake manifold bolt to hold that longer line.

So I still haven't really found a definite answer; how much preload do I need with these stock Magnum roller lifters? I'm finding stuff saying anywhere from .080"-.150"+, I just want the optimal setup for best valve control at high RPM... I have a feeling these ported heads will keep making power up top but the RPM will be limited by the valvetrain.
 
BTW I can't accurately go off "turns" of the rocker bolts for preload because it's on a shaft, they aren't on individual pedestals like a Magnum head...
 
My other stroker I just did 1/2 turn preload w/ comp pro magnum LA rockers and stock Magnum rollers. But t hey sure as hell didn't like anything much more than 5800ish rpm..
 
i´m adjusting according hughes Suggestion: .080 - .095". Never had Trouble with the stock hydraulic rollers, even at 6500 rpm.

Michael
 
MOPEkidD-3 said:
The lines are pretty dang stiff that's why I oriented the fittings that way, I could have straightened the Tee but then the lines would have had to make a tighter bend and the way it sits now there's almost no stress on the fittings or hose ends. I'll see about making a tiny bracket that comes off the farthest-back intake manifold bolt to hold that longer line.
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IMHO that is wise... you just never know what odd resonance can show up that will shake something long like that.
 
360duster said:
i´m adjusting according hughes Suggestion: .080 - .095". Never had Trouble with the stock hydraulic rollers, even at 6500 rpm.

Michael
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That's what I decided to go with; using a checking pushrod it came out to 6.735" and for the time being until I get a better set of rockers I'm just getting a set of COMP High Energy pushrods in 6.821" which should put the lifter preload around .086". Once I get upgraded rockers I'll go to some hardened Smith Bros pushrods or something similar, if I need them?
 
Got my PRW crank damper in the mail today, it comes with 3 removable counterweights but no instructions on which weight for which engine! I had to look in the PRW catalog for weights, found the ones I had, lo and behold two of them are marked with the wrong number (heavier one meant for LA 360s has the P/N for the 5.9 Magnum counterweight). Based on what I know about Magnum engines having lighter rotating assemblies I'm assuming the lighter of the 2 weights should be used with my Magnum short block...

BTW I was going to get the Pro Products damper but when I placed the order on Summit it said it wouldn't ship until mid-February, don't feel like waiting that long lol

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The numbers are kinda hard to see but they are reversed if you compare to the table I posted above, should be pretty obvious the weight on the right is bigger and heavier. Caveat Emptor!

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Well the damper is on the engine now, I did some more digging and determined the smaller of the two big weights is for sure the one for Magnum engines. Tomorrow I'll go to pick up the pushrods (hopefully) and see about getting the two rocker shaft bolts drilled.

Soon... I can feel it... lol
 
Jadaharabi said:
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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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People never knew or forget that the last rocker shaft LA's used pushrod oiling. All I can figure is they were anticipating the Magnum engines and were testing/verifying that doing valvetrain oiling like GM and Ford had done for eons would work. Lol
 
Bighead440 said:
People never knew or forget that the last rocker shaft LA's used pushrod oiling. All I can figure is they were anticipating the Magnum engines and were testing/verifying that doing valvetrain oiling like GM and Ford had done for eons would work. Lol
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Funny you mention that, someone in another thread said I was going to ruin my engine having both pushrod and rocker shaft oiling from too much oil up top... kinda late to the party, lol

I would guess that could also have been due to recently acquiring AMC which used the same size tappets but with pushrod oiling, maybe they wanted to consolidate to one type of lifter/pushrod?
 
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I got around to doing another test of the rocker oiling, this time properly... I used my radiant propane heater to warm up the oil to about 85 degrees from the 20 or so it's been from sitting in my garage with this cold-*** weather. Check it out I think it works pretty well... don't mind the banter btw my younger brothers were helping lol.

 
Today I went to install the intake manifold and got pretty annoyed, it's going to need to be milled. The bolt holes barely lined up with no intake gaskets, now with the .060" Fel-Pros it's not even close. I spent 30+ minutes trying to get it pushed down just enough to get the bolts started but there's no way...

How much do you think I should have it milled? .010" per side, or more?

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Intake is at the local machine shop now (not the shop that did the heads), I showed the head machinist the same pics above and he recommended taking .030" per side so that's what I'm having done. Should have it back before the end of the week... Then this build is pretty much done! From here it's just connect the dots... install mounts, drop engine into car, install exhaust, get it test fired and run for a minute or 2 to make sure it's all good. Then get a new radiator and hook up all the accessories etc etc

Once the intake is on I'll be moving over to my thread in the Members' Restoration forum.
 
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