The Dodge Challenger Message Board

Geez, I must seem really inconsistent! One day I'm asking questions about valvetrain components for "J" heads and today I'm asking about magnum heads. I apologize for the badgering! Just trying to get the best bang for the buck.

SO hear it goes... Magnum heads onto a LA block (360 MP shortblock 9.5:1 CR). Thoughts/Opinions?

Pros:
Closed chamber style, better quench effect, ups the CR.
Swirl port effect.
Better exhaust scavenging.
Stock 1.6 rocker ratio.
Plentiful (and hopefully cheap) in any junkyard: 92-02 V8 (5.2 and 5.9) ram, dakota, or durango.
Supposedly flows better than earlier production heads (non-mags).

Cons:
Intake manifold selection, or lack their of. Could use a non-mag one, but this would necessitate drilling new bolt holes due to the difference in intake bolt angles.
Valvtrain oiling considerations. Not a biggie, all the parts are out there, hydraulic (non-mag) or roller-hydraulic cams seem to be the only options with out major customing/fabbing.
Rockers are pedestal mounted instead of shaft mounted.

BTW magnum R/T heads are aftermarket only right? I mean they didn't come on any production vehicle?

Well there it is fellas. Post away please

I don't know enough about these Magnum heads to comment on those.

The only heads I would use on a small block at the moment are the Edelbrocks. They are the best value for money out there. OK they cost a bit of money but the performance increase to dollar ratio is very good.

Mine seem to be ok. I have the magnum RT heads 2.02/1.625. I did have them ported and polished, so it may have been more cost effective to get the Edelbrocks I like what Hughes has to say.

http://www.hughesengines.com/heads/rt_heads.asp

I had mine done to the stage II specs, but did keep the 2.02/1.625 since I'll be lucky (and broke) to hit 500hp.

Well I did a lil bit of research. Magnum R/T heads are MP aftermarket only, to say that they didn't come on ANY production vehicle (ex. Dakota R/T or Durango R/T which came with standard magnum heads.) The Magnum R/T comes in 2 flavors, 1.92/1.62 and the big boi valves 2.02/1.62.

Todd thanks for the link to the hughes site, they make some very interesting points. Hughes stage I porting has 600hp potential! Damn I agree that these heads are right up there with the W-2's and IMO well worth the magnum head to LA block conversion, which sounds like a daunting task but doesn't appear to be that difficult at all.

Check this thread out from the moparts board...
http://board.moparts.org/ubbthreads/showflat.php?Cat=&Number=394637&page=0&view=collapsed&sb=5&o=&fpart=1
Keep in mind this is with the 1.92/1.62 valves. As for price, westoaks dodge has bare pairs starting at $719.00, bare eddy's start at about $1000.00 I believe, and recon "J" heads are $600.00 assembled from aerohead racing.

Also keep in mind that the exhaust ports are improvements over the stock magnum head, which in turn is an improvement over the LA heads.
For a street occassional strip smal block head, they seem very promising as cast - with potential in the ported version. Also magnum heads can be fitted with 1.7 ratio rockers without modification.

-Ross

Another update in the Magnum head to LA block saga, one of the problems associated with the swap was intake manifold selection. Either you had to use a magnum one, or modify and LA intake due to the difference in the intake/head bolt pattern. Well I'm happy to say that edelbrock has released a magnum version of the RPM Air-Gap series manifolds. Just get the right lifters and pushrod to necessitate pushrod oiling and your on your way!

BTW if anyone is interested, the part# for the eddy intake is:
RPM Air-Gap Magnum #7577

-Ross