Wondering what some of you think about the neccesity of using a nose cone on a bravo driven boat in the 100-105mph range. I have been told that the F class boats cannot run them in APBA. I guess some of them run near these speeds. If I still have my boat into next summer, I was thinking of shortening the drive. The question is, is there any reason not to test the boat without the nosecone first? Can a bravo driven boat lose control in this circumstance like I have heard outboards do? The reason I ask, is , a couple of individuals that have knowledge of boats in this speed range, expressed hesitation in installing a nosecone. I primarily want to know if this could cause an abrupt handling issue, if tried. A fellow at mercury racing once told me that the blowout speed of the late bravo was at least in the high 80s.

Thanks.

You will have better handling, less slip, and less chance of blowout when using nose cones. If you are trying shortened drives the Mercury sportmasters and the IMCO gearcases already have the nose of the drive shaped properly.

as long as its alinged up straight. thats the part that is crucial/ the Bravo drive at 80 mph is like running a torpedo through the water without the thrust,use a nosecone on this one!!! just my suggestion, compare it to a pencil running thru the water or a big cigar/ hu /Darin

OH !!!!!!!!!TEST WITH OUT, AND THEN TEST WITH ONE AND LET US KNOW THATS WHAT ITS ALL ABOUT./ p.s. need a test driver. ha

Yeah Brad Perry, please test without & with then let us know your results, that is what i'm planning on, but i won't be ready to test for a couple month yet. so if you beat me to it i will be really curious about your results.

Problem is that I installed a nosecone on a late model bravo while increasing power significantly. I wish I hadn't done it at the same time. I might install a new XR that I have and might even shorten the XR lower and don't want to make the same mistake again, unless it is common knowledge that a cone at those speeds is the only way to go. It is a couple of individual comments I got from a couple of guys that should know their stuff that got me debating this. I guess the writing might be on the wall, from the fact merc (bravo and speedmaster) and imco only come with a lengthened torpedo...

If your boat likes a lot of trim go with something that is more rounded than pointed. The pointed cones work well with relatively level drive angles, while the rounded type are better for boats that need trim to run good. I think the Hydromotive cones will be the best bet for your type of application. I remember when I got my SS drive from IMCO they offered it with and without a nose cone. Now they only offer it with a cone. They were thinking that since my boat was small and liked trim the non coned version may be better because of the trim angle. To bad we never tried it out. With the current drive the VETTE handles very well in the 95 MPH plus range on calm water of course. One interesting thing I noticed about my boat is as I increase speed the water pressure goes up. When I am fully trimmed out the water pressure actually drops about 5 PSI. If I tap the trim down 1 tap the pressure comes back up and If I over trim the pressure will drop 8 to 10 PSI. The pick up is below the bullet of the nose cone and as I trim the water is hitting the top of the cone and creating a void around the water pick up. I filed the hole a little larger and now it keeps good pressure in my operating range, but I can imagine if the bullet was rounded the boat may go faster. What do you guys think?

It depends on the boat. I know of a 26 eliminator tunnel that runs 117 and does not use a nose cone. The boat has a bmax drive with a mercury lower. I have been in this boat many times and not once has it ever felt like it was out of control, or blow out. It launches out of the hole and has extremly good mid range pull. As for the top end it does 117. I would try a nose cone it deffinatly wont hurt it.

Tom, what kind of horsepower does the Eliminator 26 have to reach 117?

Through the years their has been a lot of controversy of the effects of nose cones. A few months back I did a test with a set of Hydromotive nose cones. At the time the best top speed on gps with my 32 active was 94.7mph. I had installed the nose cones prior to my new combination so I wasn't sure if the cones really worked. As much as I hated the idea of removing them I had to know the affect they had on my performance.
After running the 94.7 I went home and beat the cones off, cleaned up the drives and went straight back to the water. Would you believe the boat would only run 90.5 and handled like sh---t!
The next day I called over to hydromotive and asked his opinion on gains and he said 3 to 4 mph at 90 and the faster you run the bigger the gains. Anything in the 75 to 80 mph range would not see much affect from the cones,maybe better handling and a 1mph gain.
The best thing about the cones is they install easy with epoxy and can be removed. Be careful when selecting a cone many longer edged cones look great but if overtrimmed will drag and cause poor handling and lose of speed. Even a boat that requires a lot of trim can use the hydromotive cone due to the design it will not become an anchor or hurt handling.
I have since found better props and brushed 100mph safely with the aid of the cones.
Sorry so long, I had such great success I felt they deserve a long post.

Mike