Hay Joe Lucia>Just curious on the "Nomenclature" of the Chevy Small Block

[Larry E.]

When did the S/B/C become the "2nd Gen S/B"? Would the 2nd Gen S/B have what is called

"Vortex Heads or Lean Burn Heads"?? All of them or only certain years?? Thanks in advance-Larry

[Joe L.]

Re: Hay Joe Lucia>Just curious on the "Nomenclature" of the Chevy Small Block

When did the S/B/C become the "2nd Gen S/B"? Would the 2nd Gen S/B have what is called

"Vortex Heads or Lean Burn Heads"?? All of them or only certain years?? Thanks in advance-Larry

Larry------

Gen II small blocks are the 1992-97 LT1, LT4 as well as 1994-96 4.3L V-8. These engines have reverse cooling and Optispark distributors.

Gen I small blocks are, basically, all other 1955-96 small blocks as well as many manufactured and/or PRODUCTION installed after 1996. In fact, the Gen I small block is still manufactured by GM today at the Toluca, MX engine plant for use as marine and SERVICE engines. "Vortex" or "Lean Burn" heads are still Gen I small blocks.

Gen III small blocks are the new design small block first used for 1997 Corvettes and thereafter spreading to most V-8 powered GM vehicles. The only commonality these engines have with Gen I and Gen II small blocks is the cylinder bore spacing. There is no parts commonality.

Gen IV small blocks are basically the same as Gen III but with "cylinder deactivation" and/or direct injection.

[Larry E.]

Re: Hay Joe Lucia>Just curious on the "Nomenclature" of the Chevy Small Block

Larry------

Gen II small blocks are the 1992-97 LT1, LT4 as well as 1994-96 4.3L V-8. These engines have reverse cooling and Optispark distributors.

Gen I small blocks are, basically, all other 1955-96 small blocks as well as many manufactured and/or PRODUCTION installed after 1996. In fact, the Gen I small block is still manufactured by GM today at the Toluca, MX engine plant for use as marine and SERVICE engines. "Vortex" or "Lean Burn" heads are still Gen I small blocks.

Gen III small blocks are the new design small block first used for 1997 Corvettes and thereafter spreading to most V-8 powered GM vehicles. The only commonality these engines have with Gen I and Gen II small blocks is the cylinder bore spacing. There is no parts commonality.

Gen IV small blocks are basically the same as Gen III but with "cylinder deactivation" and/or direct injection.

Quick Followup Joe> Would the Gen II Small Block (eg:92-97 LT1) also have the Vortex or Lean Burn Cyl. Heads?? Would they be idendical
to the Vortex head installed on the Gen I Small Block? Thanks in advance-Larry

[Joe L.]

Re: Hay Joe Lucia>Just curious on the "Nomenclature" of the Chevy Small Block

Quick Followup Joe> Would the Gen II Small Block (eg:92-97 LT1) also have the Vortex or Lean Burn Cyl. Heads?? Would they be idendical
to the Vortex head installed on the Gen I Small Block? Thanks in advance-Larry

Larry------


First of all, and to make a correction from previous posts in this thread, there is no such thing as "lean burn" heads. The correct term is "Fast Burn".

Gen II cylinder heads are unique to Gen II engines. Gen I cylinder heads, Vortec, "Fast Burn", or otherwise, cannot be used on a Gen II engine. By the same token, Gen II cylinder heads cannot be used on a Gen I engine. Gen I and Gen II engines use different blocks and different cylinder heads compared to each other. Many internal engine parts are shared but NOT blocks and heads.