Now that GM has stuck with the LSx Platform for the forseeable future the aftermarket has gone absolutley crazy. At PRI this year there was something like 8 aftermarket head castings. There were 500 CI extra deck LSx blocks
6 bolt per cylinder World products bocks
Heads that flow in excess of 400 cfm
and a slew of other products all geared toward serious HP production
We will see 454-500 ci LSX motors with heads that flow better than most BBC race heads making 700-800+ rwhp NA in roughly the same dimensional package and weight as a regular LS1. Detune that and you will have 600 rwhp NA hydraulic cammed motors that still get 25 mpg and drive in traffic.

You can currently use a 6.0 iron block for just under 2000 hp and it cost $895 from GMPP. Or you can pick one up from a junk yard fpr about $350-450.
That block has gone well into the 6s at well over 200 MPH at 357 cubic inches and it was on a "thrown together" side project car..

Beside the LS7 427 ci Vette motor there is also a new 6.2 version that has the same basic heads just not CNCed. They may be the hot ticket to modify soon.
You can get a LS7 427 crate motor in the latest Jegs for $12900 which is not a bad deal for everything you get.


I believe every production LSX style motor in the current line up now uses the 243 head casting which was the 01-05 ZO6 head. They are a dime a dozen now. Replacement parts are plentiful and cheap. Just perfect for the weekend warrior.

There are lots of other good platform currently in production too. But the LSX platform is really making strides and should continue to do so for atleast the next 5-10 years. The longer the better for us hotrodders.