nova6.2

i have a new proyect is a 2004 chevy truck a have lq4 and a compcam xr281hr 228 230 dur 571 573 lift and my question is which head is my best choise for this proyect 243 or l92 head?

99 Blue Bird

iTrader: (3)

if u already have that cam and dont want to buy a new one go with the 243 heads. if u buy l92s u will need to buy a new intake manifold, and a set of rocker arms that will work with them cuz u cant use the rockers that will bolt up to cathedral port heads.

nova6.2

have this two sets of heads a dont have a intake

99 Blue Bird

iTrader: (3)

u have both, the l92 heads and the 243s? the cam u said u had in your original post will work better with the 243s.

nova6.2

thanks

LSwonderfull

L92 heads only need specific intake rockers, exh can use cathedral head design. I would use the L92 heads, they flow better everywhere. The cam will work with both heads. The port sizes are large for a heavy vehicle like a truck but GM uses them so go for it.

ZONES89RS

iTrader: (25)

I would sue the 243s with that cam, otherwise, get a L92/LS3 grind that is made for those bigger heads to get the most from the top end.

nova6.2

thanks bro i rather the l92

brngrhd

has anyone done a back to back 243 with proper cam VS L92 with proper cam? and CNC ported version of both with proper cams...... I'm building a 408 and going with CNC 243's because i want the most power under the curve with out getting killed up top

ZONES89RS

iTrader: (25)

Hard to even want to compare unported 243s to LS3 heads, the 243/799 casing CNCd VS a stock LS3/L92 is comparable, otherwise, L92 flow 360 on up CNCd.

brngrhd

yes i understand that....... but what about cars that are not looking for big peaks but tons of area under the curve...... well guess we will see how my 243's do on my 408 when it is done

ZONES89RS

iTrader: (25)

Ported 243s will do great man, they can work well with nearly any street combo.

brngrhd

in a truck why would you want the L92's wouldn't you want the 243's to make more low end with the weight? to me the heavier the vehicle and the taller the gear the more you want the low end and midrange...... I know comon sence....... but still people chace the hp number....... thats why my car 1970 nova with 3.25 gears is getting the 243's street car with lots of torque.

72VenturaII

iTrader: (32)

The LY6 motor that comes in new trucks have the L92 heads. I guess GM might know a thing or two about torque.

nova6.2

yes thats right a have one of them and it come aan 2008 suburban 8 holes havey duty

brngrhd

if your saying that a L92 head will make more torque then a 243 on a 6.0 then im not going to debate ANYTHING with you there are way tomany things that come into play with this then just heads...... cams intake are huge....... runner length and cam timing events

72VenturaII

iTrader: (32)

I didn't say that, but I will say that all things being the same the L92 will not give up a significant amount of torque down low but will gain a significant amount of HP on top versus the 243, especially on a 400+ cubic inch motor. I'm sure the area under the curve is larger also. Don't fall for the "L92 heads are too big" myth.

3pedals

iTrader: (3)

you can cam the L92 heads ALOT TAMER, and gain driveability, while not giving up anything on top end compared to a more radically cammed cathedral port motor.
the huge intake valve allows more air to flow into the cylinder with less cam timing.