Stock 1969 383 should I install "346" heads?

[Bad B-rad]

Long story short, I have the #'s matching engine in  my 69 Charger,383 4bbl. And the stock heads have a stuck valve in it. I can get a set of "346" casting (1971) that were just redone, for $300 bucks. So I thought I would slap them on and enjoy the car as I get the org heads fixed when ever. Question is  are the "346" heads going to effect compression ratio or anything?
I think that the "346" are the same exhaust ports as "452" or "902", but different intake ports. I also think that the "346" are open chamber just like the stock heads on my 69 383 4bbl.
Any way if I put the "346" on will I wish I had just fixed my stock heads, or will they work just fine. I am only going after a factory performance for an every day car and will be using factory HP exhaust manifolds and stock carb, and so on.(but I would like to keep the stock 383 HP compression ratio and cam)
Thanks for all your advice.

[Bad B-rad]

I have read that the "346" should be 88cc but may be 88cc-96cc
What are the chamber volumes on the 68-70 "906"?
(what did the factory say they should be/what do most stock head end up being)

[chargerbr549]

There were some minor changes between the two casting numbers but for the most part I doubt you will notice any performance difference stock for stock, and they should directly interchange with each other.

Some of the 906 heads I measured were in the 88cc range, it also depends on how many valve jobs and how much the heads have been milled.

[Bad B-rad]

ok cool that's what I kind of want to hear.
From stuff I read it said 906 heads chamber is 79cc
Then 71 346 is 79cc
72-73 346 is 81.5cc
Then I read 346 were like 88cc
so its good to read what you have measured the 906 at cause its so hard to get good info. I do not want to hurt performance as I will need every hp I can get from the stock 383.

[Bad B-rad]

Also what is the ratio of milling the head. I used to have it written down it was something like every 0.010 off bottom and take 0.013 off top(so intake fits)

[PRH]

For the most part, all years of open chamber heads are actually about 88-90cc.

From a performance standpoint, on a stock 383, running any unmodified open chamber heads(906/250/346/213/902/975/452)....... it would be very hard to discern from behind the steering wheel which heads were on the motor.

Just put the 346's on and don't worry about it.

[Bad B-rad]

That's good news,and that's what I will be doing then,thank you.

any one know the formula for milling the heads? The bottom vs top to make everything line up correctly?
Thanks again

[Sublime/Sixpack]

ok cool that's what I kind of want to hear.
From stuff I read it said 906 heads chamber is 79cc
Then 71 346 is 79cc
72-73 346 is 81.5cc
Then I read 346 were like 88cc
so its good to read what you have measured the 906 at cause its so hard to get good info. I do not want to hurt performance as I will need every hp I can get from the stock 383.

Don't go by this info. because MOST of it is wrong! If all is well with the 346 heads you have they'll work well enough on your 383.

[John_Kunkel]

Here are the airflow numbers for the BB heads.

[Bad B-rad]

From that chart,all the open chamber heads look to flow very near the same numbers.(on intake port)
How come Indy charges $100 extra for 452 casting?
I was always told (for open chamber) 906 the best, then 452 and 902.
But again that chart looks like the flow #'s are almost the same, is the difference in the porting potential? Or combustion chamber size?(although in this post it says almost all open chambers are about the same cc)

The good news is the freshly done "346" heads will go on my 383 and inexpensively let me see what I am working with.
Also it seams I am learning that I may have tossed a bunch of heads that may be just as nice as the "452" sets that I saved.(oh well can't keep everything)