if you want a LS2 Iron block this is what yu do, i know cause i have it

first you get a LQ9 then a set of 243 castings this with a stock gasket will net 11.1 CR instead of the LS2 10.9 cause of the block difference. also for intake use the LS6 intake since it does flow more then the LS2, and for cam i choose to run the TSP TV2 which in that setup puts somewhere near low 400s to the wheels.

the internals are the same between the LS2 and LQ9

as for a ls1 with that much HP over a typical 305 hp LS1 its the cam they used in the vettes

 

You just can't say it any plainer than that, Bill!

 

Thanks, thats just what I wanted to know.

 

Im not to familiar wih casting numbers. What exactly are the 243 castings and what do I have in my LQ9. I do now what LQ9 is.

 

And is 11.1CR good to run on the street. Is it too high.

 

243 are LS6/LS2/LS4 based heads they have the 64.5 cc chamber and flow the same as the 317s

11.1 is what i run daily and its fine

 

So if they flow the same then why change them to the 243's. Is it just for the added Compression. Is that compression difference change that much in power. In other words is it worth the money and time.

 

if you have a big cam its worth it, for every .5 in CR they say like 15hp. also large cams bleed off CR somewhat so more CR helps. also CR gives power thruout range. also the difference is a 1 full point from 317s to 243s

 

only diff in lq4 and 9 is the pistons right?

 

no strenght also in parts for the LQ9. LQ4 is built similar to the 5.3s/4.8s the LQ9s is built stronger like the LS2