Offshoreonly.com - More HP and prop blowout

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More HP and prop blowout

So as my huge list of things to do with the boat dwindles down I have an issue that I have yet to address and need some opinions...

Boat is a 97 Nordic heat original 525 sc now has estimated 7?? horsepower

I have always ran a 28p bravo on this boat since I've owned it and all was fine with the world...not a single blowout in turns out of the hole nothing

I have since ran the boat with the same prop same drive same everything except the HP increase and it is blowing out BAD!! I can barely get it on plane and when I do a small touch of the steering wheel and boom it blows out and you have to start over again

I'm wanting to put a -2 lower on it as I have read several great accounts of it fixing the porpoise and picking up speed as these old non stepped heats have a deep X

So I'm left wondering...is my new found blowout problem caused by the increase in power? I have a labbed 30 that I plan on running but I can't figure why all of a sudden its blowing out and will the shorty lower make it worse??

I have 1.50 gears and I'm also considering a 1.36 shorty as I have also read that some with blowout issues had it cured by the gear change...

What is everyone's thoughts on all of this??

Thanks!

Sounds like something else is wrong should still get up on plane without a problem. Maybe hub on motor is spun or prop is spun.

I checked all that....new HD coupler when motor went in but checked it anyway and it still looks new(not spun) and the hub is the metal hub with the rubber tips on it...also the HD version I believe and it as well looks new...If you baby the sh!t out of it I can get it on plane and it starts going ok but like I said if I just touch the wheel it wants to blow out....I could take turns at like 40 before the motor build without an issue...now I can't even turn when its on plane...I'm kinda stumped...everything is the same except the motor?? Could increasing the power cause the prop to blowout?? Like putting a blown big block in a pinto with 14" tires? lol

Thanks

One other variable is the weight of the engine...I'm sure I picked up some weight with the giant blower and such but I think that would help this situation specifically with more weight in the a$$end??

Did you put a low water pickup in?

No sir...it does have a nosecone always has...no LWP just a nosecone

Is it a Bravo drive, and if so does it have the fiber half moon spacer where the trim rams hook up, and if so is it installed correctly? If it’s on the wrong side of the shaft you effectively can’t trim it in all the way.

Yes it is a bravo and out of curiousity I tried that on both sides of the pin with no change...that was my first thought too hahaha

prop blows out while on plane? Is the drive at neutral when this happens?

No its when I come up on plane, while turning, and slightly when I trim it...mostly when trying to get on plane which I come up easy anyway because I have a bravo with power in front of it lol and it still does it