Currently have an LQ4 shortblock with untouched ls3 heads waiting to go on. Before i get the engine rebuild, is it necessary to switch to flat top ls2 pistons or will i make due with the stock lq4 dished ones?

What kind of power difference will they make? im not sure what to do. Engine is going in a 69 camaro street driven car only

 

What cam is it going in? With those pistons your compression is gonna be low. Alternative would be milling the heads but then PTV will be an issue with the Ls3 heads.

 

I havent chosen a cam yet. i was originally thinking about texas speed tsunami cam but i spoke to them and they told me to with an LS3 cam from their site....

 

Well I think you should do that first. I'd call Ed Curtis from flow tech he can spec you out a badazz cam but so can Futral! Give them a shout and tell them what you got and what your goals are bud.

 

The higher compression of the Ls2 pistons will help, but what will help the most is the added quench. With dished pistons, you will have virtually no quench which will make low end torque suffer. You will have to run more timing to make that up, ultimately limiting your overall compression. A 10:1 engine with .035 quench volume will be more responsive and probably make more power than an 11:1 engine with .055 quench volume.

 

So what type of milling and gasket would i need to run with my set up?