I need some help with a cam selection for my Chevy Nova SS. I am a street driver not interested in racing. I want a fairly comfortable driver on the street. The engine is the original 350 bored 030" over. I am down to two cams, the Comp Cams XE262H and the XE268H. Comp recommended the XE268H.

The heads are World Products S/R Torquer’s with 67 cc combustion chambers, 2.02” intake and 1.60” exhaust valves.
The stock flow on the head at 28” H20 is: 221 cfm for the intake at 0.500” lift, and 166 cfm for the exhaust at 0.500”.
The engine builder performed some mild pocket porting on the heads such that the exhaust to intake flow ratio should be about 70-75%.
The 350 cu. In. engine is bored 0.030” over, balanced, and the compression ratio with new hypereutectic pistons is about 9.6:1.
I am looking at the Edelbrock Performer manifold that is designed for peak torque at about 3800 rpm and peak hp at about 5300 rpm.
The Performer RPM is designed for peak torque at 4500 rpm and peak hp at 6200 rpm which may be a little high for me. Although dyno test results from many magazines show excellent numbers with this combination.

The rear end gear ratio is 3.31:1 with a 27” tall rear tire for a 60 mph highway rpm of 2500-2600.
The transmission is a standard, 4-speed Muncie M20 wide ratio.
With the relatively high gear ratio and considering that this will only be a street car with a good share of city driving, I will need a lot of low end torque and realistic fuel mileage. On a full speed run, I plan to shift at 5600-6000 rpm. I want good low end and midrange torque. I also want a a noticeable idle sound, nothing overly radical.
I am concerned about too much cam and detonation. The 268H will build less cyl pressure and be less likely to detonate. The 262H may be better suited to my rpm range.

HELP PLEASE!!