# Engine code SR85542 on 66 GTO



## dgoat8u (Jan 10, 2011)

Thanks to member "Pontiac" i found out my engine code is a service replacement motor. Does anybody else have this? Is there any way to find out what 400 block it is other than a 1967-1968? Would PHS have any info on SR motors? Thanks Guys!


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## BearGFR (Aug 25, 2008)

Google "Pontiac Engine Codes" and you should find several sites with information about how to look up what you've got (always check several - there are mistakes out there on the intertubes). Start with the 4-character casting date code by the distributor to get the model year (date codes after about July or so of any year are probably for the "next" model year). The block casting code (passenger side rear, below the head, next to where the transmission bolts up) will tell you "generally" which engine it is, lastly the two character engine code (just below where you found the "SR" number) will tell you the specific application (big car, firebird, tempest, auto trans, manual trans, etc.)

I 'spose since you've got a service replacement block though, there may or may not be an engine code on it - I'm not sure what they did in that case.

Bear


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## 68greengoat (Sep 15, 2005)

In another thread, Bear, he posted information that decoded it to a '68 400(9790071). The missing link, as you stated, is whether or not an engine code is present given that it's a service replacement block...


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## dgoat8u (Jan 10, 2011)

*SR Code*

Yep, the # by the distributor is L127 which from what i could find means it was Dec.1967, and yes, behind the #8 cyl. is the 9790071. Which is a 68-69 400 #. There is no other # on the front other than the SR #. Thanks, i'll google it and see if i can find a SR list, if there is one. Have you guys ever heard of anyone having one of these SR blocks?


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## dgoat8u (Jan 10, 2011)

*Got it*

Ok guys according to year one, the SR blocks don't have VIN codes or motor unit #'s. So it is what it is i guess.


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## 42867Goat (Apr 5, 2011)

The block in my goat is a 66' 421 service replacement. 
I found a 9782611 cast number indicating a late 1966 cast. This code was found on the underside, passenger side of the block. 
Found SR85312 along near the timing cover passenger side. 
Other numbers I pulled indicates my block was rebuilt on Jan 18, 1968 (If I remember right these were near the distributor). 
Probably bored for 428 pistons when it was rebuilt.
I think mine was a warranty return versus a stocked replacement.


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