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I'm in the midst of building a 350 vortec 4 bolt main with the 906 heads I got used with low mileage.

Its going in a Chevy C1500 RCSB

It will be carbed, a 600cfm 4 barrel with dual plane intake. Shorty headers. Alex parts vortec spring kit. Stock compression and pistons. No port work done on heads. 1.5 rockers.

Truck weighs 4240lbs with me in it and full tank of gas. Has nv3500 5 speed. 14 bolt 3.73 rear with eaton locker. 275/60/17 nittos.

I'm in a toss up between the lunati 60121 which based on all my specs lunati recommended. Or saving $70 and going with the gm lt4 hotcam.

If you arent familiar, here are the specs:

Lunati 60121

Advertised Duration (Int/Exh): 270/278
Duration @ .050 (Int/Exh): 219/227
Gross Valve Lift (Int/Exh): .515/.530
LSA/ICL: 112/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1800-6000

Gm lt4 hotcam

Duration at 050 inch Lift: 218 int./228 exh.
Advertised Intake Duration: 279
Advertised Exhaust Duration: 287
Advertised Duration: 279 int./287 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.492 in.
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.492 in.
Valve Lift with Factory Rocker Arm Ratio: 0.492 int./0.492 exh.
Lobe Separation (degrees): 112
Rpm range: 1800-5800

I'm looking for the most area possible under the curve. With shift points at 6000rpm. I'm open to other suggestions as well.

2,279 Posts
The hot cam is ground on a 3* advance.

The Lunati is ground on a 6* advance.

The Lunati cam will have more power at lower RPMs but will start to stall above about 5500 rpms.

The hot cam will be a will hold power to 6000 RPMs (confirmed several times on more than one dyno).

IMO....average power will be about the same.

The question will be whether your car most needs power below 3500 RPMs......or above 5000 RPMs.


1,473 Posts
I'd go with the Lunati. The duration between advertised and .050" show the Lunati has faster ramps (although a full ramp profile would be needed to confirm that). That leads to higher average lift. But it will require more seat pressure to control valve movement too.

Add to that you want to shift at 6K and you'd want to shift past peak power. So, you want the cam that puts the torque curve further down the RPM range, which the Lunati does with the 6° advance.
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