Mudball

Well, humm...
I have a 1999 Donzi 22ZX with a stepped hull. These weigh about 3800lbs.

With the 7.4mpi, I could hit 63 gps on a perfect day, light chop and only me. Average was about 61. Speedo showed 70 ish...

I installed an HP500 which has way more hp than the 502mag, and now I have hit 77.1 gps (after three runs) at ~5,000 rpm. The 80mph Gaffrig II speedo is now BURIED, probably showing 85 or more... I am running a stock 28p Bravo prop, Bravo 1.5 drive. I 'might' be able to hit a real 80 this spring, once the bugs are worked out and a new prop is installed to get the rpm's up...

How is it that the Scarab 22's are so much faster than the Donzi hull????

Just curious.
BTW: I use a Garmin eTrex handheld GPS unit...

Kent

502SCS

Hey Kent I sense a bit of sarcasm :-) Here is the deal the 23' Scarab SCS is not the 22' Scarab. Very different boat.
Occasionally a boat that does not have Fountain or Donzi on the side sends engineers scratching their heads.
In case my Garmin GPS is not good enough here is some factory specs Mine is almost stock with the factory Mirage plus 25P.
82 on Guage and 76 on gps.

http://www.wellcraft.com/Images/CSer...rab_SCS_98.jpg

In case that is not enough here is a news article written
http://www.popularmechanics.com/outd...tml?page=2&c=y

ok I guess we all like what we have :-)

cdscarab

According to his paperwork, my buddies 1997 22 footer only weighed 3200lbs. Thats with a 7.4/ B1.

502SCS

The 23' Scarab SCS is only 3740 ....

Whiteknuckle

I'm just having a little problem with some of these speeds. Its the math guys, the math. The math does not support these speeds. However, if "Popular Mechanics" says so I guess it's got to be true. After all, they are the authority on high performace boats.

502SCS

So the factory numbers also dont make it as well 75.1 hmmm .. Them damn engineers at Wellcraft musta left their calculaters home that day .. Call them up and educate them :-)

outriggers

I have a 97' 22 Scarab with 7.4/B1. With a 25 mirage+ 63.3 gps full of fuel. Happy speedo says 70+. From the Wellcraft link above, 75.1 mph with a 25 mirage, using a 1.5 ratio and 4920 rpm. If I figured correctly that comes up to 3.3% slip. Doug

Whiteknuckle

I'm not looking to get into a pissing match with anyone. Wellcraft Scarab is an excellent boat, they always were. However, you must realize that sometimes even engineers in the intrest of marketing tend to exagerate performance figures, because most of their customers do not know the relationships of RPM, prop pitch, and all the things that effect it. If you want to believe those figures, let the pleasure be all yours.

Steve Snider

Whaaaaaats up? Freezing ass up there? The Scarab runs too good for the power in it. You know I know the boat. I think the X-dimension is higher than most (factory rigger set up a fast one that day) and if I recall he has John Janaky do the Mirage prop. Later, Steve

Outdrive1

I think Ron is right about the slip factor, it takes my boat 5150 rpm 1.5 gear ratio 28 pitch Bravo 1 to get 75.4 mph on the gps. It's also a 30' hull with a step in it. I dont think you can turn 81 with a 25 pitch prop @5000 rpm and a 1.5 drive. I'm running around 17% slip wich is fairly effiecient.