[Ron Sutton]

Hey Chad,

First, everything I'm recommending is based off of 1.65 roller rockers (Crower stainless are my recommendation by far).

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If the timeline requires an "off the shelf" camshaft, I recommend:
Comp Cams Grind: 286XOS
* Careful, there are two versions - Get PN: 12-657-5

Duration @ .050: Int=256° Exh=262°
106° LSA (Lobe Separation Angle)
Install this cam at 6° advanced

Lobe lift: Int=366" Exh=.362"
Valve lift with 1.65 Rockers: Int=604" Exh=.597"
* Actually slightly different with hot lash calculated in.

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But what it really needs is a custom grind. Same price, just takes a while longer to get.

The cam profile I recommend includes the intake lobe profile from the cam above ... 286XOS ... and the exhaust lobe profile from the 290XOS ... with a wider LSA at 108°.

The specs would look like this:

Duration @ .050: Int=256° Exh=266°
108° LSA (Lobe Separation Angle)
Install this cam at 6° advanced

Lobe lift: Int=366" Exh=.366"
Valve lift with 1.65 Rockers: Int=604" Exh=.604"
* Actually slightly different with hot lash calculated in.

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With either cam at 6° advance, you may need to flycut the intake valve pocket on the piston a bit more. Maybe not. Ideally, you want .090" on the intake & .110" on the exhaust.

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More tips:
a. You do need to run the carb spacer they allow.
b. Run gapless piston rings (to get all the dynamic compression possible) with a low tension oil ring (for less parasitic loss).
c. The exhaust will be critical to maximum power. I'll map it out next & make a separate post.

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This dyno curve shows the off-the-shelf cam & the custom cam. The difference from 5250 rpm & up is key to a fast race car down the straights. This is the middle of the 3 cam profiles I was considering.

It will not be a torque monster. But it won't be lame either. the key to being fast with this combo is to gear the car to hit the 6300 rpm rev limiter 4-6' before the lift point.

The throttle won't be as sensitive. The car won't be edgy on exit about tire spin. The driver won't have to egg-shell the throttle. The driver will be able to roll the throttle on early & rapidly ... starting the acceleration ramp earlier.

From corner exit to the the next turn, it will be the best combo, if geared correctly.