I am planning on installing a 2005 LQ4 in my truck shortly with an EPS 222/226 Cam and the mods in my signature. Is there much to gain from going from the stock 317 heads to stock 243 heads? If not, I will just save my time and money for a set of ported ones.

Thanks for your help!

 

No they flow the same, the 243's just have more compression. Have Richard at WCCH run his stage 2 port program on the 243's and then you'll gain.

http://www.proheads.com/WCCH%20LS6.html

 

Not trying to TJ. but would these heads on a 5.3 drop or raise compression?

 

stock they would drop, you have to mill them .030'' to bring compression back up.

 

243's would drop compression -- 317's would drop compression... a lot.

 

I think they are are worth it, you can get them for 300 bucks and they will gain you about 20hp, the extra compression helps in out quit a bit, you will go from 9.5-1 to close to 10.5-1

 

I say they are worth it too, if you can find a set cheap.

 

Yep. 317 is a 72cc chamber and 243 is 64.5cc chamber.

 

They drop compression on a 5.3 but he is installing them on a 6.0 so they would raise compression.

 

I wanna drop since i wanna go FI