Extension Boxes

BlownScarabI · 09-17-2007, 11:02 PM

I was wondering if any one has recently installed extension boxes on a single engine scarab? I currently have a single engine 21 scarab I with 540hp running a bravo one. I have the motor and the boat where I want them, but I think I can tweak some more power with the outdrive setup. I currently run a 27p 3 blade prop. With this setup I get 84mph. But I think I could get more with a better setup. I have been looking into nose cones, extension boxes and shorter lowers, but wanted to see what everyone else has to say.

Hot Boat · 09-20-2007, 06:21 PM

[QUOTE= I have been looking into nose cones, extension boxes and shorter lowers, but wanted to if anyone else has to say.[/QUOTE]

Use all the above.

But 84 is would be fast enough for me in a 21' boat.

BlownScarabI · 09-20-2007, 10:31 PM

Thanks, shooting for 90, any recomendations on who's product to use.

Hot Boat · 09-21-2007, 12:05 AM

try a land a sea stern jack and lab the prop it might get you where you want with out spending a lot of $$$ and a lot of work.

I sanded some of the factory hook out of my Hull and gained some MPH.

also at those speeds you might want to look into a nose cone to make the drive more efficent.

I hope you have hydrolic steering.

BlownScarabI · 09-21-2007, 12:40 PM

Thanks for the info, and yes I have a dual ram setup.

hdtvned · 09-21-2007, 10:34 PM

84 mph WOW good stuff! I have a Scarab 1 as well. I am doing a 65-68 with a 383 NA stroker. Sorry I cant offer any advice on the extension thing but I would like to share ideas. 90 + would be unreal. We hit 73 with wind and current once and it was great.
Please give me some details of your boat.
I am trying to get to 75
Did you do anything to to bottom?
Does your engine hatch/ swim platform weigh 200+lbs? Mine does and I cant see why unless its a balance thing.
I would like to share some pics with you. I did some cool mods to make mine look newer.
Good luck with the 90+
Ned hdtvned@yahoo.com

puder · 09-22-2007, 01:07 PM

I've got a land and sea box I'd sell! PM for details.

BlownScarabI · 09-23-2007, 11:33 AM

Ned, your boat sounds nice send me some picks jbeckerm5@yahoo.com, or just post some, I'll try to post a few of mine in a day or two. Heres some details, I no longer have platforms, hull is stock. I have a 400 sb with a blower dyno tuned at 540hp. I also have a bravo one, because the alfa blew up. My steering is a Mayfair dual ram set up, got to get rid of the cable system, its just dangerous at speed. Now I'm just trying to fiqure out how to get a little more mph from out drive mods.

Mike J · 10-08-2007, 06:33 PM

Puder Im Restoring my old 26Ls and im thinking of trying
a box, I must have your old info so send me a Email.
Mike J.

John B · 10-08-2007, 08:38 PM

Scarab22, What is a racing 468 merc 502 cu?