I don't run a Scarab (but I do have a deep v) and those numbers you posted sound about right.
you Scarab-boys can chime-in and correct me i may be off a bit.
IMO, if you trim-up those trs's to air-out that bad-boy and get those bigblocks to spin 4600-4800, you may see low to mid 60's, especially in salt, decent numbers for a heavy V.

BTW, what part of the delta do you play? If I see ya, I will make sure to say hi.
If you are ever running the bay, love to run with ya, plenty room to air-out for extended WOT runs without the worry of lake-lice. We usually play out around Racoon Straits, great runs from SAMs out past the gate.

Be Safe and wear those lanyards,
GC

I live on the Sac River. Haven't spent enough time in the Delta but I'm up for it. Let me know when you're going out and I'll meet ya. If you're ever out on the river let me know. I get out and run around in the evening a couple nights a week. I call it therapy.