When checking speeds via gps it is important to have the speed filtering feature set properly for intended purposes. This feature allows time based averaging of speeds to smooth readings and make them more meaningful. You could get an erroneously high reading by having the filtering times set low (say 1 sec), or low readings by having the filtering times set too high (say 30 sec). Many gps units have this feature. This can be a big deal in offshore performance boat racing as they watch (disqualify) for an overpowered boat "breaking out" or exceeding the max speed for thier respective class.

BTW... I personnally run a Scarab and everyone knows that they are hands down the best and fastest boats on the water

BT

Oops, someone doesn't believe me.

Roby

I had a scarab 23 SCS for 5 years with the 502 MPI(415) 25 pitch prop (not labed) and it is truly a 70+ MPH boat. Here are the perfomance figure for 1997 23'3" SCS. Powerboat Feburay 1997 top speed Radar 73.2 at 4900 with a 25 pitch prop. Zero to 15 sec 64MPH. Boating magazine April 1997 top speed 74.1 at 5000RPM with 502MPI 25 pitch prop. The 23 scarab is an awesome boat I still miss mine.

Here's a simple prop slip calculator that's helped me many times. Also, Bravo 4 blade props are actually 1 pitch less than what's stamped on the prop. If you're running a 28p bravo, then enter 27p into the calculator. Hope this helps...

http://www.boatpropellers.com/propcalc.html

I'm coming up with about 7% slip too. 502/415 , 25p Mirage Plus, 74 GPS , 5000rpm

Some amazing #s. My 98 22 scarab 7.4 b1 labbed 25mp. Best - 64.2 on fumes. Just me in the boat. Nordscog gps.

I don't understand why they are not still making this 23' Scarab, or someone did not buy the molds for it after Wellcraft stopped making performance boats. It had to be the most effecient hull on the water. In fact, it sound like they were pretty close to rewritting the physics book. Remember, the prop does not care what is making it turn, whether it is a 502 or a 283. At 5000 engine RPM with a 1.5:1 drive and 25 inch prop, the speeds I am hearing here are very remarkable.

The 23 SCS was agreat boat but very expensive. Powerboat magazine printed the list price at 57800.00 in 1997. That with the 502 and full hydraulic steering.

Hey Nitro/max good to keep hearing things that make the calculator wiz's scratch their heads. You ever get down south I have an 97 Orange SCS that I will take you for a ride in ..with minor tuning replicates the same numbers the the factory says it ran out of the show room ( wont say how fast that is because of the lip lashing I got last time :-) ). My boat has 130 hours after my ride down the river today and love it .. Did however find out the hard way not to jump on an Allison with a 250ss on the back .. guy said it went 101 on GPS whew .. fast little boat .. hmm wonder how he takes 3 footers ... story might change

yeah them ally outboards will open a can of whoop azz in good water wont they!!