70 Big Block Chevy Head ???
 

im taking my original motor apart for a rebuild and ran in to something i need some help with.
my car was built the second week of Dec. 69 and one head is

L..12..8...3931063...with flat seat plugs
and the other is
L..2..9....3964290...with taper seat plugs

i know early cars could have either head but shouldnt both heads have flat seat plugs?

thanks Donnie

Re: 70 Big Block Chevy Head ???
 

Not really.They produced the #290 head with either tapered or flat spark plug seats.Your example of two different heads is unique,but not impossible.
What is the Tonawanda assembled date on your engine pad?

Re: 70 Big Block Chevy Head ???
 

Rick,
its TI205 CTW on the engine pad but according to my P.O.P. the I should be a 1
so Dec. 5th right?

be kind of a pain in the a$$ getting 4 flat seat 13/16 and 4 taper seat 5/8 to do a plug change.

Re: 70 Big Block Chevy Head ???
 

THE HEADS ARE ONE YEAR /APART//

Re: 70 Big Block Chevy Head ???
 

So whats your point??
ever had a can of soup that keeps getting pushed around in the back of the cupboard and before you new it. its out of date.

Re: 70 Big Block Chevy Head ???
 

Donnie,

What's the block casting date?

Re: 70 Big Block Chevy Head ???
 

O.K. heres the scoop after Barry and I posted I got to thinking and called the second owner tonight. I remembered him asking me a couple of years ago if it still had a big plug and small plug head, but at the time I didn't think nothing of it sense it was setting in the corner of the garage and I was running the 502.

Well, he trashed the passenger side head in 1986 thats why I have a 063 big plug head, so now it looks like im in the market for a Nov. early Dec. 69 small plug taper seat 290 head.

Howard,
hope to see you and the family in Nashville this year.

Donnie