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finally figured out my engine #s

lak2004

lak2004

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So I got most of my old engine out of my blazer and got the #s off the heads and block and finally found out what it is.

Block #:14093638, 87-95 350 2 or 4 bolt mains, roller or flat cam, 1pc rear main

Heads: 3998991, 72-73 307/350 75cc

Anything special about either one? Think I might end up keeping the block and rebuilding it for a spare.
 
The head casting number is a "hecho in Mexico" target master special. Those heads are the heavy casting heads and are generally a good head. I'm not familiar with that block number but if it's from a truck it will not be a roller cam. Only the cars got the roller cams then starting in 1996 with the Vortec engine trucks had roller cams as well.
 
The block is a decent block , whether its 2 or 4 bolt . Use good parts and ARP bolts and rebuild it .

The heads are good after they are machined for large valves , one of the better flowing pedestrian heads ( not high performance ) . Stock the intakes are tiny at 1.72 inch . They had hard seats though for unleaded and decent ports ......... if they are from 72-73

The other 991's are like said above , off the Mexican made crates .

I'd take em in a heartbeat if you were closer and add them to my collection :thumb:
 
pauly383 said:
The block is a decent block , whether its 2 or 4 bolt . Use good parts and ARP bolts and rebuild it .

The heads are good after they are machined for large valves , one of the better flowing pedestrian heads ( not high performance ) . Stock the intakes are tiny at 1.72 inch . They had hard seats though for unleaded and decent ports .

I'd take em in a heartbeat if you were closer and add them to my collection :thumb:
Click to expand...

Every "991" head i've ever seen had 1.94"/1.5" valves. :confused:
 
i have a set of 991 heads in my shop, they always get looked over, as i thought they were junky heads, i ussually wind up puttin the 882 heads on....4x4high, the 991's are indeed a ''good'' head?
 
pauly383 said:
The 307's didn't have 1.94's and they indeed had 991's . GM recycled the casting number on the Mexican crates , though most of those were 993's .
Click to expand...

Oh crap, i think i got confused. The 993's are what i was thinking about. :doah:You're correct thought that 307's never had the 1.94" valve.

Also the 993's are only a 350 head.
 
maybe 993's i have...i know they are 9's instead of 8's and the last number is 1 place off from the 882, so they're either 991 or 993, still i thought they were junk and have kept them around incase i ever needed a set for cores!
 
Theres always a buyer for stock heads that aren't cracked , some guys are limited to stock castings for certain race classes and will sit for hours with a grinder making them work . And rebuilders want them for stock replacement builds .

Nothings junk . I have a stack of em , lots of different castings :

IM000249.jpg
 
If this is a hijack, I apologize, but it's related. I was messing around under the hood of my Jimmy and discovered the motor has "Goodwrench" valve covers. Since they're the same color and condition as the rest of the motor, I'm assuming some PO put a replacement engine in. Is there someway to tell? I know where the engine serial numbers were in the 60s&70s; has this changed? What do I look for.
 
ttt can anyone tell me what the heads are worth? i need to sell some stuff fast, i have a for sale thread if anyone is interested.

thanks
 
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