The engine in my car has always been a mystery since day 1 (previous owner, long story) , so now that I pulled off the 416 heads to put on to a 350, I got to see the pistons.
I thought that an LG4 has dished pistons, hence the 8.5:1CR, and the L69 had flat tops, hence the 9.5:1 or whatever.

These sure look like flat top pistons:

pic1
pic2

does this look like an LG4, L69, or other? When I pull the motor, i'll check casting #'s on the block, but that won't be for a while....
Any thoughts?

 

Looks like the LG4 I yanked out of my T/A.

 

From https://www.thirdgen.org/techbb2/sho...hreadid=261488

"The '82-'84 3rd gen LG4's had lower compression because they had dished pistons in them, which, when combined with the 58cc chamber 416 heads, produced 8.5:1 compression ratio. The L69's and '85-'86 LG4's & LB9's had flat top pistons with 4 valve reliefs that, when combined with the 58cc chamber 416 heads, produced 9.5:1 compression ratio. '87-up used a slight dish piston with 4 valve reliefs that reduced compression to 9.3:1."

 

Looks like the LE9 van engine that came in my 1983, except trucks/vans/SUVs came with the 601 heads and a 350 truck cam.

That means that it was over 9.5:1? Flattops w/4 valve reliefs, 52 CC chambers, steel shim head gasket?

 

ok, so five7, you think this may be an L69, since it has flat tops?

Anyone know which casting # would be for an LG4, and which would be L69?
I figure once I pull the motor out, if it's an LG4, i'll probably drop it off at the wreckers to recycle for me, but if it's an L69, I *might* be able to sell it, due to it's popularity... oooh, 305 HO!

 

My 86 LG4 had flattops when i took it apart, Sonix. I think only the early lg4's had the dished pistons.

 

Both the L69 and LG4 used the same castings.

Even if it was an L69, I wouldn't count on anyone paying anything for it.

 

The LU5 Crossfire also had the 4-relief flat-tops.

 

Well this ought to be fun bringing to the auto recycler.... I hope they can just take it off my hands, and I don't have to pay a fee to get rid of it....

 

If you don't want it, you could just stick an ad in the Bargain Finder and give it away for free to whoever will come and take it away.