Flying Tomato

Test boat: 1995 Python 24x7
540cid, 625hp, Bravo 1 1995 outdrive

Baseline: Boat would run 82-83 gps.

Test 1: Installed nosecone, but in my haste did not blend in as per instructions. Top speed was 81, boat was SCARY! Chine walking all over the place. Very little chine walking before.

Test 2: Blended in the nosecone. Most of the crazy chine walking went away, except at top speed. I saw a top speed of 85.5 which is my all time best!!!!!!!!!!!! I probably had another 1-2 mph but the boat got scary and had to get out of the throttle.

So: nosecone got me a solid 2-3 mph and for 100 bucks that is awesome.

Lesson: Take your time and blend it in really good and smooth. I used automotive filler (bondo). The boat was totally different when the nosecone was NOT blended in correctly.

rgrgoog

iTrader: (3)

What nosecones did you use? The IMCOs or Hydromotives? I have some IMCOs I am waiting to put on this winter. Hopefully I see some gains like you did.

Inspector

iTrader: (1)

Did the engine RPM go up or down? Did you calculate prop slip before and after installation?

Thanks.

Flying Tomato

It was a hydromotive cone. I did gain 100 rpms. Prop slip stayed the same at 7 percent.

ezstriper

thanks for the info....want try one on mine now that it will run into the 80's...what did you use to install with ? thanks Rob

Flying Tomato

The hydromotive nosecone comes with an epoxy to glue on the nosecone. Then, I used Bondo automotive body filler to do the "blend in". Bondo is super easy to sand down.

Lee

articfriends

iTrader: (1)

I just put one on my spare drive in the end of Aug, I used Hydromotives supplied epoxy again as it worked well for years the last time I put one on. Instead of Bondo I like to use "all metal" as it is supposed to be more impervious to water. I have said this in past post too about blending it: WELL BLENDED worked well for me and I mean I ground, sanded and filled over and over again on the last one until it looked like a perfect casting and it worked real well, when I first put on the first one it was squirrelly and did nothing for my speed but my boat WAS much slower then also, I went back later and really blended the hell out of it. Do NOT install one on a boat without hydraulic steering as it WILL make your boat wander/ chine walk because of the added length, the slightest turn from center will amplify ANY play you have in your steering cable!!!!!!! Smitty

Thunderstruck

I gained 86 to 92 with Teague leading edge cones. Cheapest speed I ever got. Lot's of doubters on OSO, whatever......

Twin O/B Sonic

I've experimented w/them a bunch but on O/B's only. Results were always the same though.
It drops the bow, requires full up trim to counter act the added stern lift front the added surface/planing area of the cones.

On one 80 MPH single O/B 21' boat the speed stayed the same but went from a perfect, efficient, neutral trim setting to get there to requiring full positive trim which wastes a bunch of thrust.
On my old 24' Sonic twin O/B they did exact same thing but lost 3 MPH's!
You I/O guys may be seeing increases due to the weight you are carrying in the stern but am still surprised.
To see improved speed w/o slip and R's changing doesn't make much sense though.
My slip #'s always went through the roof.
Biggest advantage we see w/the O/B's is the low water p/u's but I am becoming a fan of transom mounted p/u's though.
Of course another difference between the O/B's and I/O's is X dimension. When we can surface our cases the negative of the cone goes away while we still get the advantage of low water p/u.
In my experience, bellow 90 or so, cones are snake oil.

272bajadriver

iTrader: (1)

Flying tomato how is the automotive bondo holding up? I need to sand my bob's nosecone and fill it up again as one of my outboard lowers has chunks of it coming off. I was told not to use automotive bondo, is yours holding up so far in the water. Has anyone else use automotive bondo over a long period of time and how has it worked?