I see summit has 2 different 6.0 iron blocks available. One is for the lq4/9 replacement and the other ly6. The ly6 replacement is a little more then 1100 bucks and the lq4 is almost 1700. What are the real differences in these blocks ? From what I�ve read, the blocks themselves are very close, yet the price is almost half more from one to the other.
Thanks for any help.

 

I'm not really sure, but going to take a guess that one is current production with AFM and the other is old style non-AFM.

Try Google-ing LQ4 and LY6 and see if you can decipher from any specs that are out there.

 

I'm betting you nailed it right there. The new Gen III blocks are getting in short supply, thereby raising the price of admission (the old supply/demand issue). Meanwhile there are PLENTY of the newer Gen IV to be had.

 

i thought they stopped making gen 3 blocks for a while, then started back up again

 

But are they STILL making them? There is no technical reason the Gen III blocks would cost more; it has to be a supply issue, IMHO.

 

i was told they started back up due to demand. yet the gen 4 is cheaper. it doesn't make sense

 

They'd likely rather you bought the late one so they wouldn't have to bother making the early ones anymore. lol
Buy the late one. Probably a better block anyway.

 

Different factories in different countries? :shrug:

 

Same thing with LS3 heads. Cheapest things going.

 

One is a Gen 3 block the other is a Gen 4 block.


Chevrolet Performance 12679002 Details

Cast-Iron Production LS-Series Engine Blocks
Direct replacement for Gen III Block LQ4 & LQ9
Production cast iron block
Production oiling system
6-bolt main bearing caps
4.000" finished bore (101.60mm)
9.240" deck height


Chevrolet Performance 12609999 Details

Cast-Iron Production LS-Series Engine Blocks
Direct replacement for 2008-2010 Gen IV Block RPO, LY6 & L96
Production cast iron block
Production oiling system
6-bolt main bearing caps
4.000" finished bore (101.60mm)
9.240" deck height

No provisions for Active Fuel Management
Supports 500+ Horsepower

 

Almost all Chevrolet parts that are currently available but NOT used in production vehicles is due to the Dealer network requesting that item. If it's not available it's because the dealers are not selling that item. If the dealers get requests then at some point the factory will make a run. Usually during the summer when tooling and vacations are occurring. Once production starts it's impossible to get press or foundry time for some special part. You could stand outside the foundry in Defiance Ohio with a bull horn! Best bet is to get as many people as possible to request the part from the dealer. That always works.