Aluminum 340 heads

[cuda]

Has anyone put aluminum heads on there 340? I am considering a set on my cuda. Id like to know what kind you used,were u bought them,what is the difference in hp,was it worth it,would you do it again etc. I have always gone by the policy of if it dont break dont fix it. My engine is fine and have no problems at this point but i have always been wondering about this. Presently i have stock cast O heads on my 340. Also my mods are 510 lift crane cam,10.5.1 speed pro pistons,edelbroke torker intake,holley 750 carb. Let me know. Cuda Brian

[IMNCARN82]

I went with Eddy RPM's.  The old Mopar guy who helped with my build suggested them. I didn't know any better. But it upped the compression some. My old ones could have used a valve job anyway.And I always wanted alum. heads.  Went with Crane gold rockers. I did not change the cam.(.474)Just heads.I did upgrade the ignition.  It is a tad faster.Was told Eddy's are like 70h.p. ?  Not sure.  No dyno yet.  No port/polish yet either. They do shave some weight too. Way lighter.   Was it worth it... I guess.   I'd do it again too.     RPM airgap manifold/650 carb.  i live at 7000 ft. still wondering about that carb. being too small. 

[Chryco Psycho]

A friend of mine who works at a speed shop said he looked at over 10 sets of Eddy heads before he bought a set that were not badly core shifted

[Chryco Psycho]

Alum heads change a number of other things , alum absorbs more heat so to make up fo rthe heat loss you really need one more point of compression , most alum head fail to compensate for the so you ultimatly make kess compression unless you change pistons , you also get more heat under hood as the alum releases more of the compression heat underhood

[IMNCARN82]

Ya' I wish I had some good numbers before and after.   What is "core shifted"?  Now you make me wonder if I didn't do more harm than good.  Hard to tell with the time between it running.  What could I do to get more out of them? Or help with what you spoke of Neil?    Sorry to hijack 'cuda.

[Chryco Psycho]

core shift os just lack of quality control where the casting is not in line with where the ports etc need to be so when you port match the port is already too big on one side & has to be cut heavily on the opposite side to line up the ports again
 A friend did a 440 using RPM heads a few yaers back & after spending 3 months fighting all the issues to actually fit them he made 2 more HP & I ported them as well , lot of time & $$ for 2 hp 

[IMNCARN82]

live and learn i guess.  before they went on we checked them out real close. Didn't see anything too bad. i looked at cleaning up the cast heads and everything was close to 900 bucks. But havn't got a good place to go either.C-C.c is the best place for me so far. Thanks C.P.     would you take them off? 

[Chryco Psycho]

no , i would leave them on unless there is a serious reason to remove them

[moper]

If you simply want to change them, you could. But there's no real reason to unless you believe your irons to be worn or not done well. It's a big expense to upgrade to aluminum. I've had a totally different experience with Edelbrocks than CP has. There are a few issues of core shift friends have noted on RPMs. The ones I know of were heads being CNC ported and got dangerously thin because of it. Core shift has no effect until you start to try to enlarge and max out the port and do not take the shift into account (like a CNC program that cant). As RPMs already flow what a set of well ported irons do, it wouldnt make sense to port them to install on yours. I've used over ten sets in the past 4 years, and never had a serious issue with them, even with the CNCd ones. I have had tight guides on every single head, and some seats out of round seats... typical for all aftermarket heads, and they will and do make horsepower.

[71chally416]

Do you have the OLD style Torker or the new one?

[cuda]

Not sure if its new or old torker,it was in place when i bought it 10 yrs ago. That said id guess old.

[matt63]

I'm running Eddy Magnum heads.  The engine is zero decked for good quench and 10.5:1 compression.  If I had to do it again I might just go with the std Eddy heads.  I've never had it dyno'd but I'm happy with them.

[71chally416]

Not sure if its new or old torker,it was in place when i bought it 10 yrs ago. That said id guess old.

I've never heard glowing reviews on either one but the newer one is better than the older one. They just don't work well on 340's. You can probably pick up a bunch of power just switching to a Performer RPM AG. Some picks to distinguish one from the other.

[Chryco Psycho]

that might be a better place to put the $$ just switch to the new RPM air gap intake
 maybe they send the junk heads to Canaduh know how difficult it is to return them 

[moper]

Perhaps that's it Neil...lol
Maybe because they are so hard to return, you guys are much more particular with what you like and only want the best. Dont worry, with the dollar sagging, you'll have a 1:1 exchange rate pretty soon and it might get easier...