ANYONE RUNNING A COMP CAM XE262 IN A 340?

CFD244 said

Hi Folks

Looking to do a mild build 340 using the XE262. My calculated static compression ratio (used lower compression height pistons than OEM), I am still getting about 9.4:1 with the slugs .0175 above the deck and an .039 head gasket with (iron heads). Using the XE262's Intake closing event occurring at 57* ATDC, that leaves my dynamic compression at around 8 to 1 +/-. So, based on the science, this cam will not work well on pump gas. Looking for any real world experience with this cam. Comp recommended it for my package, even when I thought that my CR was going to be over 10.

I could retard it 4* since it has 4* advance ground in, but I am not sure if it would make the engine a dud.

P.S. I already have the cam.

What say Ye?

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I would not retard the cam. Degree it to verify cam card timing. Retarding the cam tends to raise the max torque RPM point which thus moves the max HP higher. It does not change the toque value. For a punchy street machine you want that low RPM torque. Then deal with your timing needs from there.
Another point to consider is modern fuels with ethanol blends. Fuel that is 100% gasoline has a stoichiometric value of 14.7:1. E100 has a stoichiometric more like 8.5:1. E10 fuel stoichiometric is close to 14.1:1. What this indicates is the jet sizes need to be a couple of sizes larger. This will aid detonation resistance.
GT350 Garage has an excellent 2 Youtube videos where Matt discusses this in depth. Do not let the GT350 trip you going in the door, as the information presented is not specific to the hood emblem.
Matt also in this series has a video that goes over ignition timing setup.