bbc head APPLICATION
 

I just picked up a set of Closed chamber big block square port heads.
One is dated D 13 70 ( casting #291 )
and one is dated H 24 70 ( casting # 840 )
..What would the application be for?
....1970 LS6...or 396/375 or both?
https://www.yenko.net/ubbthreads/imag...iggthumpup.gif

Re: bbc head APPLICATION
 

The 840 heads are the 68-69 closed chamber head for L78/L72 applications...the 291 is the 70 model year for LS6 and L78. I've never seen a 1970 dated 840 head...perhaps it is a service replacement part..??? I'm sure some of the part number gurus will know...so, what you gonna' build???

wilma

Re: bbc head APPLICATION
 

291s were used on late 69 L-78/L-72. Seems like someone on this site talked about a car with 840 on one side, and 291 on the other.

Re: bbc head APPLICATION
 

It would be interesting to see if they both have the same style spark plugs...

wilma

Re: bbc head APPLICATION
 

I have a mis-matched set like this too but the dates are a lot farther apart.
James

Re: bbc head APPLICATION
 

I will get some photos of the plug area and the dates..but that is what I thought ..
...840's were 1967,68 & 69 ( not 70 )
thanks for the help https://www.yenko.net/ubbthreads/imag...lins/beers.gif

Re: bbc head APPLICATION
 

John,

That '840 with the '70 date would be a service replacement
only - as others here have suggested. Regarding the spark
plug seats, it would be interesting to see if the '70 dated
head has a non-peanut style seat. One more application for
those heads was the L/71 ( so that's L/71, L/72, L/78 ) https://www.yenko.net/ubbthreads/imag...mlins/grin.gif
Nuch

Re: bbc head APPLICATION
 

Here is the photo of the 840 head that I thought was
dated H 24 70 ...or am I misreading it?
...or is it H 24 7 https://www.yenko.net/ubbthreads/imag...lins/dunno.gif

Re: bbc head APPLICATION
 

Here is the other side of the same head https://www.yenko.net/ubbthreads/imag...lins/smile.gif

Re: bbc head APPLICATION
 

here is the 291 head dated D 13 70 https://www.yenko.net/ubbthreads/imag...lins/smile.gif