Scored A Set Of Magnum R/T's!!!!!

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opnwhlracer

opnwhlracer

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100 bucks a piece!!! With a fresh valve job, bead blasted & clean,all wrapped in plastic. 2.02 intakes and 60cc chambers. Guy said they are off a 408 stroker motor he bought about 7-8 years ago. Ran the R/T's for about 10,000 miles and put Indy heads on it. Any issues with these heads I need to be aware of? I plan to put these on the 0 deck 318 I am in the process of building. KB167's +.040. Will I have to clearance the push rod holes for a flat tappet cam on these? I want to run a mechanical cam in this thing too, so I'm thinking the Hughes SS rockers would be nice. Any thoughts? Thanks guys!!
 
Nice heads! The MP, R/T heads can go 300 cfm w/a 2.02 valve. Sweet. IIRC, I need to be checked on this, but the pushrod holes should be OK. Regardless, the fix is easy, under a couple of hours if your used to working on stuff, on a bench with good tools.

Also, again, IIRC, and yep, again, I'll need to be double checked, but I do think very much so that these heads are not the cracked prone hindering head of the regular Magnum style head. I remember some where, that the area was addressed pretty well on cooling and something about internals being better to prevent the cracking issues.

You should be ready to rock and roll with these heads.
 
Cool, I guess I did pretty well to snag these then. One thing I did notice about them is the intake port castings are pretty rough, and the valve guides have no bronze liners. They do have SS valve seat inserts. Other than that they are really nice. Can anyone chime in on a cam recommendation? This motor will be going in a 69 Dart Hardtop, 4-speed, 3:55 gear, keeping car light as possible. Will be a fun street car with an occasional trip to the strip. Keep in mind the 1.6 rockers in the Magnum and a lift restriction of about .525" due to the Magnum tall valve guides. Thanks again guys!
 
Check out the latest Engine Master article on the 318.

http://www.popularhotrodding.com/tech/0810phr_chrysler_318_engine/viewall.html

They got 425hp out mildly ported Engine Quest heads,on a very similiar build you have,your R/T'S will out flow these!
Need to do valve guide to retainer clearance and I would go with the same cam...
Comp XE275HL. Specs for this stick come to 231/237 degrees duration at .050, and .525-inch lift with a 1.5:1 rocker ratio, all on a 110-degree lobe separation angle.Of course with the stock 1.6 rockers you will have .560-inch lift...
Here is an older article with 360 heads milled and same cam,which I am doing the same build with mildly ported J heads 2.02/1.60.....
http://www.popularhotrodding.com/enginemasters/articles/mopar/0667em_mopar_318_engine/index.html
OH,about your score....You luck dog !!!
 
Look at a Lunati 60401 grind.specs are 213/220 @ .050/lift with 1.6 .483 Int, .499 Ehx.Mild grind.If you want to step it up,Try the Comp 274XE.Specs (with 1.6) lift .519 Int/.523 Exh.230 int/236 @ .050.More of a street strip grind.
 
Oh,You will need oil thru lifters and pushrods to lube the magnum style rockers and magnum head bolts to bolt to a LA block.
 
Yes, that PHR build is the one that I am basically copying. I was saving up to get the EQ heads when these R/T's came up on Craigslist. I think the guy that sold them to me was having money problems and needed the cash as he tried to sell me about everything he had in his garage! I could not get the money out of my wallet fast enough!!
 
What left in his garage,mopar related?Or am I too late...
LOL
 
I like TXDarts cam, machine the head for it's use. The comp valve springs will be needed for this machine work. There skinnier than MoPars spring.
With a manual trans, I like to hit the cam hard. Also, look into this for, "Food for thought", that is, if as cast isn't good enuff for ya. Ha ha ha ha!!!

http://shadydellspeedshop.com/magnumrt.htm
 
Wow! Now that's some flow! Well, let's see.....light 8mm Mag valves, some mild port work, cut down the valve guides for a higher lift cam, beehive springs, roller rockers, a 7000 rpm 318? Naaaaa......maybe??
 
Yes,Rumble! I would kill to have a set of those.With a good Hyd roller,Nasty Hp.And drivability.
 
What kind of HP do you guys think I might get out of this combo? What if I went .060" over? That would make it a 328. I could really do some chebby huntin' with a set up like this. Smoked by a 318. I love it!
 
No need to go .060 over. The amount of cubes and resulting HP is minimal at best. Just clean up the bores or go .030 if you must and build accordingly.

HP levels can be ruffly guesstamated (LOL) by a basic CFM X's 2. While this is a laymans formula, it is good enuff to invision the possibility.

Due note that the MoPar has a few advantages over a Chevy engine that the cry over not having or pay dearly to get. Remember that the real key for any engine and/or car is power to weight ratio and suspension to get going.

Considering this head is on a 318, even in stock form, the R/T heads should be able to make some seriously killer power on the 318 whilest out roaming the street. I do not think you'll need to port them at all.
 
Yep, 18 degree valve angle and slant plugs are something the cheebie guys never had until the aftermarket came out with it in the 80's, and we have it from the factory since what, 1967? And then the high swirl combustion chambers of the late 80's early 90's. Mopar has been WAY ahead of the curve on cyl. head design for a long time.
 
TXDart said:
Check out the latest Engine Master article on the 318.

http://www.popularhotrodding.com/tech/0810phr_chrysler_318_engine/viewall.html

They got 425hp out mildly ported Engine Quest heads,on a very similiar build you have,your R/T'S will out flow these!
Need to do valve guide to retainer clearance and I would go with the same cam...
Comp XE275HL. Specs for this stick come to 231/237 degrees duration at .050, and .525-inch lift with a 1.5:1 rocker ratio, all on a 110-degree lobe separation angle.Of course with the stock 1.6 rockers you will have .560-inch lift...
Here is an older article with 360 heads milled and same cam,which I am doing the same build with mildly ported J heads 2.02/1.60.....
http://www.popularhotrodding.com/enginemasters/articles/mopar/0667em_mopar_318_engine/index.html
OH,about your score....You luck dog !!!
Click to expand...

I like the 275HL cam too but that older article shows that using 1.6s on such an aggressive grind can be a tricky proposition. On that occasion it actually cost power. I guess the lighter 8mm stem valves on the later build may have just edged it in the right direction.
 
There is a good bit to that and Hyd. cams. When we used to race'em, the higher lift was good until you push it to far and the lifter (Is what we believe to be) not able to handle the additional stress/load/accerated rate from a violant jump in ratio geoometry.

Solid cammed engines can handle this.
 
I really like the idea of a mechanical cam in this engine. Seems the way to go with a 4-speed car and an engine that will see most of it's life in the upper RPM ranges. Lifters are cheaper and not as sensitive to oiling issues, no preload to deal with when checking push rod length, ability to deal with fast ramp rates, but the cheaper lifters would be offset by the adjustable roller rocker set-up I would have to run. Besides, I just like the way a mechanical cam sounds.
 
Salty Dog said:
Doesn't Crane stil have the super strong ductile rocker arms?
Click to expand...

yes for LA engines....but not for magnum engines..

hughes makes a very nice shaft rocker setup for the magnum heads
 
MoparAnglia said:
I like the 275HL cam too but that older article shows that using 1.6s on such an aggressive grind can be a tricky proposition. On that occasion it actually cost power. I guess the lighter 8mm stem valves on the later build may have just edged it in the right direction.
Click to expand...
Agreed
That is why on my build I am going with J heads 2.02/160 mildly ported and 1.5 273 adjustable rockers (budget build).
Now if I had those R/T 'S....
 
Yes, that Hughes set-up is the one I have my eye on. Should bolt right in place of the stock rockers. With beehive springs should be a nice high rpm valve train. I'll take some pics of the R/T's and post them this week. They are really nice heads.
 
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