like captyarr, mine is 29Scarab twin 383's, 400hp/425tq dyno and tune by Bob at Full Throttle Marine ,,,, ran 73 at 5400 ,,,, before rebuilds 350's 300hp/?tq it ran 67 at 4900 ,,,,, boat weigh's 6500/dry ,, about 7300 fuel,gear,2 adults

1989 Scarab 31 Excel with 454 Mags, Comp Cams Extreme Marine cams, lifters, springs, push rods, roller rockers, Edlebrock RPM Airgap intake and Holley 4150 750 CFM carbs with 23 pitch Mercury mirage props and I run low 70's at 5200 rpm. I ran 65-67mph with the stock engines. Going to try 25 pitch to see what that does fro me.

Just as a comparable, I'm running HP500s in my twin step 33', and am seeing about 82 (perfect conditions, light load) at 5200 RPMs with 28 pitch props.

1988 30 panther, 29 pitch 3 blade with cup , bravo 1 outdrives 1.5 ratio, 70 MPH at 4250 RPM. Motors make 425hp at that rpm WOT and its close to WOT at 70 MPH GPS. With 177 blowers the 330hp 454s make 600ft lbs torque at 2500 RPM through 4500 RPM and 457hp at 4500 RPM with cam change. Rev limiter set at 4700 RPM.;).

Lol, my 30 TRS Panther (same hull as yours) ran 72+/- depending conditions witb a little warmed over Merc 420's labbed 3 blades, approx 450hp. So 420/side with labbed props should get you 70.

Now just shy of 80 with ~570hp.

Thanks for the information guys. I've been talking to my engine guy about making mine 500 hp over the winter. Which I'm thinking should get me over 70 mph. Rookie, which transmissions are you running? and aren't you running blowers now?
Thanks again.