I have a question on how to tell if the LB9 engine block, I brought is a true LB9 engine block. I brought a complete LB9 engine. Its from a 1991 IROC with 40 thousand miles on it. It has the water pump install. It also has a complete TPI set-up also. It has the MAP Solenoid on the Plunem that is a factory set-up.

So here is where I have a problem with what I brought after getting home and finding this web site here that has all this imformation that can help me. I'm hoping the shop did not not pull a fast one on me. The engine was over spray black again to make it look new. After cleaning it I found writing on the oil pan saying its a 1991 Chevy Pick-up 1500. The whole TPI set-up looks really clean like almost new or steam cleaned. The paper work match what I thought I brought

Okay here is what listed on my block. Right front below the right head is a boss with this number grouping as it is.

V O 7 2 6 B L J
1 V V 1 1 1 4 9 7 5

Center Block Rear below Distributor on the flange

14093627

Left Rear next to Head Flange

G139

GM 5.0 LG
SGI

I hoping that I have what I was sold to be correct as a LB9 engine. Anyone can help or Go to the dealer for the low down.

 

From www.mortec.com:

14093627...305...87-91...2...Roller cam, one-piece rear seal

LB9 would use that block. The real difference between LB9 and LO3 is in the induction/heads/cam, not the block.

 

Did they tell you it was from a 91 IROC? Kinda weird since they stopped production in '90. If thats what they told you then I would be weary of what other lies they told you. Gotta watch out for shops like this. Always good to bring a freind with you who knows what he/she is talking about.

 

That answers your question right there. 5.0 as in 5.0 Liters. My 350 was GM 5.7 LG

 

damnit you beat me to it....ahhhhhhhhhh

 

A LB9 is the RPO for a 5.0 TPI engine option in both the Camaro/Firebird. The LB9 used the same GM 5.0 block casting as in other carlines. The Block is not special to 3rd Gen Cars.

 

I think, since the L03 and LB9 are both 305 blocks, they will have the same markings. The difference was in the other parts, the blocks were the same. Just like the LG4 and L69 blocks were the same.