Pure stock type rebuild: Performer 340 heads or J-Heads

Hi,

I've been trying to stick with the numbers-matching game with my 1972 340 'Cuda. I planned on a FAST-style motor or pure stock/stock appearing with 500 HP. Now, my plan is to have 400-425 Hp and 400-425 Ft. Lbs. Torque with the original steel crank (don't really want to bother with a stroker motor right now). I'll be doing a camshaft, higher compression pistons and the rest will be pretty much stock. My Thermoquad was restored by Scott Smith.

Anyway, I'm kind of getting tired of spending big money to restore parts back to assembly line condition and with the correct dates and what not (my fan clutch, wiper motor, exhaust manifolds, carb, and most other parts under the hood have been correctly restored or are NOS).

Now, I'm staring at these 1972 J-heads and I'm just not feeling much love for them. If they go to Shady Dell, I'm guessing it will be pretty expensive to have them flow to the max with new valves, springs, etc.

So, I'm thinking about picking up an old LD340 intake manifold and just run the Performer RPM 340 E-heads. Paint them blue and go from there. Maybe TTI headers down the road if I decide to remove the stock exhaust manifolds. But, that would be it. Just the internal mods I mentioned above and what I just mentioned.

Any thoughts? BTW, I'm not interested in competing in FAST or Pure Stock. This is just for my own pleasure.

What is it that you are asking...Exactly?

I go with the small chamber Edelbrocks and a light weight flat top piston. Personally I'd do a stroker now and change the heads later, IMO the most power for the dollar.

If you are talking about a complete rebuild of the J heads, don't do it. The cost would be not much less than the Edelbrocks, and the Edelbrocks ootb will out perform the Js. If the Js are in pretty good shape, guides ok, seats not too recessed, etc, I would go with them. I would lap the valves to see what the seat and valve surface looks like and I would mill them to get good quench. The amount to mill would be determined by your piston to deck number and which head gasket you choose. Good quench is .035 to .045. You can go tighter, and many do, but these are safe numbers. If you mill more than .020 to .030, you will need to space up the rocker shafts or buy custom pushrods of the correct length. The intake manifold surface must be milled as well. It cost $145.00 at my local shop to mill my heads.

The deciding factor is going to be the condition of the Js, or the condition of your bank account. The quick and easy way is the Eddies.

IF you reaaly want to stay with "factory" stuff, you can port the J heads and get decent perf. 15 years ago before Eddy heads were available i home ported some J heads on a 408 stroker and went 11.20 at 3500 lbs in a Challenger. Had decent heads for a decent price been available, i would have went that route.

I know this isnt the for sale section, but if your after an OEM look, I have a set of 596 smogger heads that will hang with Edelbrocks up to .500", then they are about 10 cfm behind at .550" and then die at .600". Fresh never run...stainless valves (1.94/1.60) good solid lift springs (or remove the inners for a mild hyd cam)...iron adjustable rockers are avail, too.

I'd sell them WAY cheaper than redoing the J-heads or popping for Eddy's.

PM if you're interested.

Thank you guys for your suggestions. I guess I'm just a bit burned-out on the car and I'm not in the mood to sink maximum dollars into the J-heads. But, maybe the J-heads will work out.

I may just ship the heads down to Shady Dell or bring the whole motor down there for a rebuild.

I've emailed the owner and he has been helpful in giving me some direction. Obviously, stroking it will give me more power.

I guess it comes down to how much money and time I want to spend on this. Just in a period of frustration right now...lol.

If you want a stock-looking head that flows well, consider IMM's RHS-X heads.

Quote:

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If you want a stock-looking head that flows well, consider IMM's RHS-X heads.

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Or a w-2.