First off. For those of you who don't know, the ZZ430 was a limited production engine that Chevy did a bit ago. It was a ZZ4 short block with fast burn heads and an LT4 Hotcam setup. I plan on building this setup with one exception. GM now has an updated version of the fast burn heads which is basically the same head but with it now having LS6 Beehive valve springs for higher RPM. But let's flash back for a second so I can tell you how I ended up here.

The LT4 Hotcam kit with 1.6:1 roller rockers has .525 In and .525 Ex. Oddly enough, the valve springs in that kit, can go a maximum of .525 lift. Now even though the kit comes with those springs, it doesn't give me a warm and fuzzy being that the cam's lift is the max for the spring. These were the springs that they originally put in the fast burn heads. Here are the specs on those springs:

Number of Springs Per Valve: Single Outside Diameter of Outer Spring (in): 1.320 in. Coil Bind Height (in): 1.220 in. Damper Spring Included: No Spring Rate (lbs/in): 332 lbs./in. Inside Diameter of Outer Spring (in): 0.802 in. Inside Diameter of Inner Spring (in): 0.802 in. Valve Spring Style: Standard Coated: No

Flash forward to now. The new fast burn heads now use the LS6 Beehive springs. Can somone tell me just by looking at the specs if these beehive springs will work with the LT4 hot cam? Here are the specs on the new springs.

Factory LS6 Valvespring:

•Beehive style springs
•1.800" installed height @ 90 Lbs pressure
•Used on LS3 / LS9 heads
•Max lift .570"
•1.250" Height, 295 Lbs pressure
•Use with cap 10166344 and keeper 10166345


And of course you will need the cam specs:

Cam Style: Hydraulic roller tappet Basic Operating RPM Range: Idle-6,000 Intake Duration at 050 inch Lift: 218 Exhaust Duration at 050 inch Lift: 228 Duration at 050 inch Lift: 218 int./228 exh. Intake Valve Lift with Factory Rocker Arm Ratio: 0.525 in. Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.525 in. Valve Lift with Factory Rocker Arm Ratio: 0.525 int./0.525 exh. Lobe Separation (degrees): 112

Can anyone give me some direction here? At initial glance, being that it says the LS6 springs can handle up to .570 of lift, I am pretty sure I am good there. But will the rockers and cam work with those springs? Keep in mine, I have never gone any further into an engine besides bolting on cylinder heads and intake, so I don't have much knowledge with matching these components. However, I am no dummy when it comes to cars and I can do the install no problem. Oh, and lastly, I know there are better cams and heads out there. I am set on this combination. So please no comments suggesting me to go a different route etc. I just want to know if the cam and rockers will work with those beehive springs. Thanks everyone for any help.