Big Block Billy

Hi ! Just went for the Konrad 540's on friends Kevlar 1982 38' Scarab. Upgraded from Trs. switching props and drives to turn opposite was done as was suggested. The same props as were on the trs drives were used. The problem is alot of cavitation and it takes a while to plane off . When it does it is scary fast. It seems that it really lifts the transom. I have been told to use spacers and also to change to 5 blade herrings. Also never ran boat with drives set up turning like the boat left the factory. I'm thinking of just swapping props and drives and seeing what that does. Also wondering if I need bigger diameter props . The Konrads are 1 1/2 " shorter than Trs. After dropping $26,000 at the marina ( which is considerably cheap) We don't want to waste money buying spacers at $ 800 a pop and $ 7000 in props to find out were not setup right. Maybe someone has some answers. I really appreaciate it. Going on poker run this weekend out of Port Washington NY. Thanks, BBB

throttleup

Post your performance numbers and we can go from there.

Julie

Biggus

iTrader: (1)

I'm heading to Long Island this afternoon. I'd be happy to help.

Give me a call,

Kurt from Konrad

715-410-0735

[email protected]

PatriYacht

T2x or Brownie made a post a long time ago about why everyone should spin their props out. In short it said spinning in made v's unstable and made cats want to lean out in turns. Generally turning in helps lift the bow but in your case maybe the higher x dimension is unable to lift the bow. What props are you running now? If you are running Mirages, changing to Bravo's will help with the cavitation and add bow lift.

pb

Billy,
Hopefuuly MrCig(Mark) will see this post or you can PM him. He did the Konrad conversion on a 38 Cig flat deck and was having close to the same issues if not the exact same. I am sure he can give you some advice.

Paul

MrCIG

iTrader: (1)

I had the same issues with the Konrads as you. I still turn my props out which is the way they always have been. I added a 1" spacer which made a big difference when getting on plane.
I am currently running Hydromotive QIV. These are the same props I ran last year I just had them re-hubbed. I didn't pick up any speed but I also didn't lose any. Speed would have been a bonus but the durability is what I was looking for.
I will be trying a set of P5X's this weekend just to see the difference.

If I get a chance I would like to try the P5X's with out the spacers also.

In the Picture this is without the spacers and Bravo props.
Cruise range was better with the Bravos and top end was the same. I havn't tryed them again after the spacers.

Mark

Crazyhorse

Don't try to drink with Mr Cig. He'll win.

tomcat

It is important to test things one at a time. If I were you I would swap the drives back and compare that to the way the boat felt before. The Konrad is 1.65" shorter which could help or hinder you depending on how close you were to cavitating before and what props you are using.

On the Rtech/Konrad project boat we already had the TRS drives fairly high, with the propshaft about 4.5" below the hull. Three blade props were useless, but Bravo four blades liked it. When we installed the Konrad drives, the four blades were still OK, but a set of Hydromotive P5s were better. A 1" spacer and the four blades might have worked too, but we've got poker runs to go to.

PatriYacht

5 blades from any source will probably reduce the cavitation but Hydros and Merc props cost a lot less and some of the prop shops have tryout programs.

Hang Time 27

Definately try the 5+blade props. Guy in my area has high x-dimension 32 Dominator with single teague Bravo. . Slipped bad even with with bravo-1 4blade. Went to 5 blade herring -- hooked him right up - planed out fine and picked up 4mph GPS (88-92).