Vance
05-24-2009, 04:59:02 PM
I have owned this Z since January of this year and I knew it did not have the original motor. What I am trying to figure out is, what does it have. The engine plate by the passenger cylinder head does not have any stamping on it( it may have been machined down). The block casting has the numbers 3970010 and the cylinder heads are casting number 354434 with a date of C21 77. From what I have learned, the block is ofter referred to as 010 block and is a desirable block. The heads appear to have been used on 262,267 and 305's. So, it looks to me that I have a good block with small cylinder heads. The manifold and carb were swapped out for Edlebrock pieces so I cant gleem any info from them. Any info and insights would be appreciated. Vance
li0nhart123
05-24-2009, 05:20:42 PM
It's hard to say for sure what car the block was originally from...according to the literature that block was used in many '69 - to at least '75 passenger cars ...mainly Chevelles, Nova's and Camaro's though.
http://i128.photobucket.com/albums/p199/li0nhart123/3970010SBCIdentification.jpg
hope that helps a bit
CorkyE
05-24-2009, 05:52:39 PM
From http://www.mortec.com/castnum.htm
3970010....350...69-80...2 or 4
354434.....75-79...262/267/305...60cc chambers
I would start by looking for a good set of cyl heads, just IMHO...
Twisted_Metal
05-24-2009, 06:26:27 PM
Someone put 305 heads on a 350 block to boost the compression a bit.
It's better than a 305! :D
RICARDO1969
05-24-2009, 07:10:53 PM
Someone put 305 heads on a 350 block to boost the compression a bit.
It's better than a 305! :D
IS THAT A COMMON THING? ARE THE 305 HEADS WORTH ANYTHING PERFORMANCE WISE. JUST WONDERING I HAVE NO INTEREST IN ANYTHING 305.
Twisted_Metal
05-24-2009, 08:04:58 PM
Fairly common mod..... 305 heads are a dime a dozen.
They don't flow real well so the improvement isn't very great for the larger displacement engine. (If the heads still have the small valves.)
Vance
05-25-2009, 01:58:03 PM
Thanks for the responses. The answers have cleared up a lot of the questions I had about the performance of the motor. It definitly wont run on regular gas and it runs out of steam above 4000 rpm. Guess thats what you get with a small combustion chamber and small valves. I'll have to live with it for a while while I finish up the suspension and the subframes. Vance
