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View Full Version : HYDROMOTIVE or bravo1prop wt better???



bajabob 718
09-09-2010, 03:00 PM
ok we are running a26 bravo1 at 5100 at 69.8 need 200 more rpm wondering ifa 26 HYDROMOTIVE will do better does any body try them ????try a lab mirage 25 was slower

ThrottleUp Props
09-09-2010, 03:51 PM
What hull, engine and drive package do you have?

Julie

bajabob 718
09-09-2010, 05:20 PM
26vee hull 502dyno598hp 150bravodrive it my buddys boat excaburer http://www.youtube.com/watch?v=eueoPCbSC1M

jeffswav
09-09-2010, 08:03 PM
I have a 23p hydro that I borrowed from a buddy. On my boat I picked up 100 RPM but lost 2 MPH. (I normally run a lab mirage 25p) The prop slip was about 9% and great out of the hole and turns. But I am looking for speed so I put the Mirage back on. Every boat is different and his may work better.

Donskihp
09-09-2010, 08:20 PM
I'm running a Hydromotive, because with my boats high X-dinension,the Brovo 1 had too much transome lift, making coming out of the hole harder and giving me too much slippage. Hydromotive corrected my problems.

ThrottleUp Props
09-10-2010, 08:50 AM
So 598 HP....at what RPM?

What is the year of the hull?

Julie

bajabob 718
09-10-2010, 02:31 PM
5200rpm with 600pounds tq do not no year of the boat . it may be 1999. i no he said it has a pad on the bottom

502/525hp
09-10-2010, 03:36 PM
Julie we spoke a little while ago about this boat.It's a 2000 wellcraft excalibur. dry wt 5000lb.The engine made 670tq @3700 but has 600 tq @5200 and 598 hp@51-5200.Stopped the dyno at 5200 because it leveled out.The 25 labbed mirage plus ran 5500 but went 2 mph slower.A 25 mirage plus stock runs 5300 but is still 1-1/2 mph slower than the bravo 1 26.A regular mirage 25 did just spun under accelleration.I'M ADDING A 1/2 "spacer next week to see if I can get more leverage to pick up the bow more.I can trim to the limit with both props with no porpoising.The trim is set to one more inch than merc. specs. by the factory.:driving: Can you get me over 70 legit.I can't rest.Help a brother out.I'll mail the prop.

ThrottleUp Props
09-13-2010, 08:32 AM
Julie we spoke a little while ago about this boat.It's a 2000 wellcraft excalibur. dry wt 5000lb.The engine made 670tq @3700 but has 600 tq @5200 and 598 hp@51-5200.Stopped the dyno at 5200 because it leveled out.The 25 labbed mirage plus ran 5500 but went 2 mph slower.A 25 mirage plus stock runs 5300 but is still 1-1/2 mph slower than the bravo 1 26.A regular mirage 25 did just spun under accelleration.I'M ADDING A 1/2 "spacer next week to see if I can get more leverage to pick up the bow more.I can trim to the limit with both props with no porpoising.The trim is set to one more inch than merc. specs. by the factory.:driving: Can you get me over 70 legit.I can't rest.Help a brother out.I'll mail the prop.

So what is your gear ratio and what is your gps speed....need a refresh on the info, please?

Julie

ThrottleUp Props
09-13-2010, 08:36 AM
ok we are running a26 bravo1 at 5100 at 69.8 need 200 more rpm wondering ifa 26 HYDROMOTIVE will do better does any body try them ????try a lab mirage 25 was slower

With all the data you have supplied I am calculating 13% slip with the 26P Bravo 1. The normal range for a 4B propeller is 10-14%. So you do not have excessive slip. It is possible the Hydro may perform well on your hull, traditionally they are suited for stepped hulls. But if you have a pretty heavy power package than a Hydro can work wonders. There is only one way to find out for sure......TEST ONE if you can. But as always proceed with caution...the Hydro is going to lift the STERN. It has the opposite effect of the Bravo I bow lifter.

Julie

502/525hp
09-13-2010, 06:56 PM
Thanks Julie.It's a 1.5 ratio and the gps speed was 69.8 @ 5100-5200. :driving: The seedo was more friendly 75 mph.BAJA and I are speaking about the same boat.

ThrottleUp Props
09-14-2010, 01:53 PM
So what happened with the spacer? Also describe any behavior changes.

Julie

502/525hp
09-14-2010, 05:34 PM
I didn't install it yet.Any thoughts from you ahead of time??I was told to try it by an offshore boat builder.He said he has had luck with it in the past.He thinks not enough of my boat is out of the water and this will change the leverage angle.Maybe this weekend.I'll let you know what happens.Then you can tell me what I need.Thanks,Bob