keep ls6 top or sell for ls3 top?
keep ls6 top or sell for ls3 top? hello all. i am building a forged bottom end lq4 right now. my plans have changed a lot since i started this build (was going turbo, now running n2o, ect...) And before i send out my 243 heads for some work, i am wondering if i should sell them and go for a ls3 top end kit. i am leaning towards a gt11 cam either way, along with a 200hp wet shot. just looking for some opinions. engine is going in my 02 ws6 auto...
thanks in advance,
Bruce
thanks in advance,
Bruce
Ported 243 top will make more power then a stock ls3/l92 top, but will cost more. If It's a Gen4 siamese LQ4 you can have it sonic checked and if it checks out, bore it to ls3 cubes.
Great question! I don't think this has ever been discussed before...
The 243 heads have smaller chambers and smaller runners, which generally translates into a more responsive engine with very good low and mid range power.
The LS3 style heads flow a lot, so they can make higher peak power, especially when you ditch the long runner plastic intakes.
Since you have an LQ4, I would want the 243 heads since you have a dished piston to deal with. Without milling either head, you're looking at about 9.8:1 with the LS3 heads versus 10.3:1 with the 243. You can obviously mill the heads for more compression, but the larger valves in the LS3 will run into PTV issues sooner than the smaller valves in the 243 head.
The 243 heads have smaller chambers and smaller runners, which generally translates into a more responsive engine with very good low and mid range power.
The LS3 style heads flow a lot, so they can make higher peak power, especially when you ditch the long runner plastic intakes.
Since you have an LQ4, I would want the 243 heads since you have a dished piston to deal with. Without milling either head, you're looking at about 9.8:1 with the LS3 heads versus 10.3:1 with the 243. You can obviously mill the heads for more compression, but the larger valves in the LS3 will run into PTV issues sooner than the smaller valves in the 243 head.
you guys rock! thanks again for the help! hoping to have all but the 200 shot done this summer(really thinking i want a money maker kit). but my 100 shot plate will still be there... which reminds me, will my ls6 intake flow enough? i would hate to get all this done and have the intake be the weak link....
