Engine - Head compatibility

[Grizzly]

I have some older parts ( 60's ) and access to an 87 350 block cheap ($0) in good shape, still running. Can anyone give me rule of thumb as to when the blocks were changed so that earlier major parts (heads, cams, intakes) can't be used.

 

[Hib Halverson]

You don't specifiy which "major" parts you have from the 60s or, when in the 60s those parts were made, but generally, early Gen 1 parts will fit an 87 Gen 1 block.

 

[Stallion]

What exactly does "Gen 1" mean as in blocks?

 

[JohnZ]

The "Gen II" (late LT-1) block started in the Corvette in '92, and was used later in Camaro and Caprice models. It differed by having reverse-flow cooling, a gear-driven water pump, front-mounted Opti-Spark distributor, etc., and as such none of these components (including blocks, heads, and intakes) are backward-compatible with the previous 1955-91 "Gen 1" engines, but the cranks, rods, and pistons are.

 

[Stallion]

Is Gen II what is currently being used in LS-1, 2, 6?

 

[MaineShark]

The LS-1 and LS-6 are Gen III engines. They are another complete redesign, and share almost no dimensions with the previous blocks.

Joe

 

[Hib Halverson]

Gen 1 = L81, L83, L98 and all small block V8s back to 1955 and up to 1991
Gen 1E = early Vortec truck engines up to 2000 in some cases
Gen 2 = LT1, LT4, L99. 92-96 in Corvette and B-car, 97 in Camaro.
Gen 3= LS1, LS6 plus various Vortec truck engines, 97-04 in Corvette, currently in some trucks.
Gen 4 = LS2 and the coming LS7. 05-up in Corvette and mid-sized SUVs.

 

[Jack]

I have some older parts ( 60's ) and access to an 87 350 block cheap ($0) in good shape, still running. Can anyone give me rule of thumb as to when the blocks were changed so that earlier major parts (heads, cams, intakes) can't be used.

Not all but Most 87 and up CARs (not trucks) with 350 have roller cam and shorter pushrods ... OE roller lifter is taller than flat tappet, therefore uses a shorter pushrod. Fairly simple to tell ... pull out a pushrod and measure length ... a roller cam OE pushrod measures about 7.2" ... the other OE pr's measure about 7.8". Sixties heads will fit 87 block. 87 & up heads and intakes have a different angle on the intake bolts but sixties intake can be made to work with 87 & up heads. 87 will probably have a 1-piece rear main seal ... so any crank from about 85 and back will not work in 87 block without an expensive seal adapter. Also, one-piece seal cranks have a different bolt circle at rear so older flywheels won't fit. The newer 1-piece seal cranks are balanced different than older 2-piece seal cranks ... so, the cranks aren't practical to interchange. A set of OE replacement hydraulic roller lifters WHOLESALES for about $125/16 versus $20/16 wholesale for hyd flat tappets. G'luck.
JACK:gap