Are 305 G blocks worth anything? What are the differances between a G and say a regular 305? I tried the search, bugt G is too short of term to search on. Any info would be appreciated!

 

G block? As in the 8th digit of the VIN, engine code G?

That's the L69 engine. AKA 305 H.O. It was produced from 1983-1988 and could only be had in the Z28, Formula/Trans Am, and the Monte Carlo SS. I don't believe the block is any different, however the camshaft is a little stronger than the standard LG4, or H code engine. The heads should be the same, as well as the rods and crank. The compression ratio on all L69 engines was 9.5:1, and only the later 85+ LG4 engines got the 9.5:1 ratio. Earlier LG4s had only 8.6:1.

The L69 made a significant amount more power than the LG4. Ratings were around 45 more HP depending on year. The cam played a good part, but the rest was in manifolds and tuning.

Do a search for L69 and you'll come up with all the specifics you need.

 

On what would be the right rear of the engine, if you were standing in front of it, is the cast 5.0L G then the casting number of the block. The casting number says it is an 86 block that had a 4bl on it. It had a TPI setup on it when I bought it, the numbers come back as an 85 TPI setup. Thanks for all the info! Much appreciated.