340 Heads - Looking for information

[1badfish]

Hey all! Been a while, I have come across a set of 340 heads that I am interested in and would like some opinions on them. Low mileage heads off a 1970 340 with about 60,000miles on it. I would have the heads completely rebuilt at some point and use for a future build. I am just wondering are these heads still a good option for 340 builds or should I look at some bolt on options? I am wanting to maintain the "stock" look but want best bang for buck. I currently have magnum heads ported and polished but they do not have the 2.02 valves so keep that in mind when comparing my options.

Any idea on price? I am assuming they should be priced as bare heads as the valves and springs are likely not reusable?

Thanks all and hope everyone is doing well. I am planning on being at BJ Scottsdale if anyone is going to be down there.

Dave

[RUNCHARGER]

Magnum heads are superior to 340 heads. The Magnums flow well and the combustion chamber is superior. If you can get machining done cheaply you could buy the 340 heads however where I'm at it's cheaper to buy new aluminum heads rather than rebuild the old stuff.

[1badfish]

Thanks Runcharger! Had a feeling that was the case. I definitely intend to keep my Magnum heads if I rebuild my engine, this would be for a future build. And you are definitely right on the machine costs these days.

[blown motor]

Those are J heads. If they are stock they won't have 2.02 valves.

[Chryco Psycho]

Depends on the year 70/71 had 2.02 valves in J castings .
I agree with Runcharger , 308 or Magnum castings are faar superior to J castings & yes you could add 2.02 valves to Magnums but may not gain anything .

[1badfish]

Depends on the year 70/71 had 2.02 valves in J castings .
I agree with Runcharger , 308 or Magnum castings are faar superior to J castings & yes you could add 2.02 valves to Magnums but may not gain anything .

Thanks Neal! We are do for a catch up. I'll PM you. Hope all is well.

Dave

[6bblgt]

& those heads appear to be from 1971 model year engine 

260th & 266th day of 1970

[Ohiowoodchuck]

Not to high jack but how would you rate the w2 heads. Are they worth the money by the time you factor in the purchase of a intake or are you better off going aluminum.

[crackedback]

If you want a stock look from the rebuild, those are a decent starting point.     

In reality, if you had to make a choice, it's better to get a set of that head with 1.88 valves and cut them to 2.02 if you want the bigger valve. 

I've had a bunch of those heads and can't sell them for $150 a pair in either 1.88 or 2.02 configuration.  Thrown many sets in a scrap run.   I'd give 80-100 for the pair if I needed cores.

[erik70rt]

I used a set of J heads on a 416 stroker.  They had the 2.02 valves, were ported and worked fine with an eagle kit and Comp magnum 292 cam - got about 500hp.  I am about to use another set on a current 340 build of a 340 6 pack (not T/A block or heads).  All depends on what you want to do. 

For cores, I've seen prices in the 250 - 300 range lately for large valve J heads.  I sold a set of small valve heads not too long ago for $200. 

Since you're up on PEI, I have to ask - what is your favorite Stompin' Tom song??    

[RUNCHARGER]

If you really want to make some steam the W2 heads are a great choice. Some casting #'s can have problems though so you have to do a bit of detective work to see which ones are better. If I was building a serious smallblock they would probably be my first choice. My son has a W2 360 in his Dakota and his Ferd and Chebbie big block friends keep their mouth shut when they're around it.

[Chryco Psycho]

W2 heads kick serious butt , amazing heads , they cost some $$ but the time you buy speicial rockers intake & valve covers but worth every penny !!

[1badfish]

W2 heads would have been my first choice but if I recall they will not work with my 6 Pack intake?

Haha favorite bud the spud song is definitely the hockey song. Hahaha

Asking price is $800 CDN + shipping so I'm guessing I'll pass.

[Chryco Psycho]

You can do a lot better with $800 than J castings

[Ohiowoodchuck]

Would a guy be better off just buying new w2 heads or trying to source a used set. What casting number would you try to avoid.