346 or 906 heads

[72demon440]

I have a set of 906 heads from my 440 and the 383 I am disassembling has 346 heads on it, any opinions on which ones are better? I had not even heard of the 346s until now. thanks, Jared

 

[abodyjoe]

don't 346 heads have hardened seats in them?

 

[72demon440]

that would be good if they did!

 

[RustyRatRod]

They do.

 

[JohnRR]

depends on the date code of the 346's either way they are both open chamber 90cc chamber heads and flow roughly 220cfm , nothing real spectacular about either head if they are both stock.

 

[mopar7172]

i would go with the 906 heads

 

[Dubob]

Years ago I went trhu several sets of the "hardened seat" heads such as the 346. Had five or six of them that were cracked between the exhaust and intake valves. They were hardened by induction hardening. This only tempers the metal of the head material for a few thousanths of an inch. Thru the process of grinding seats etc eventually that material is ground away and your left with basically no hardening. I would personally have the hardened exhaust seat installed in either set you go with. I would also look over the 342's good to make sure they arent already cracked in that area.

 

[72demon440]

thanks for the heads up!