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Need a little throttlin' advice...

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Old 06-12-2011, 10:04 PM
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Default Need a little throttlin' advice...

Here's the situation: I've got a single-step 35 Reggiecraft with IMCO boxes. The previous owner ran -2 lowers and IMCO Xtreme drives with some big blower motors, so in keeping with the "if you go out, you must go up" this winter I bought some -2s and added a bit more horsepower. I went from stock 502s to 540s that are making 570 hp and 622 ft/lbs.

The handling characteristics of the boat are relatively unchanged...it's like its on rails at 80 mph, turns nicely, and planes out even quicker than it did with the standard length lowers.

HOWEVER...I took it out in some lovely Lake Michigan three footers...the kind that come at you three or four at a time and then either smooth out or turn into a 5 foot hole...and when I would leave the water, my re-entry was like somebody hit the brakes. I was running 45-50 mph, and when I would come back in, the props would totally blow out. I am certain this will eventually cause a quick death to my drives...so I'm looking for advice. With the standard lowers, I always ran the boat at 3-4 pins on the drive trim and varied the tabs according to the wave conditions. Never had ANYTHING like this blowout occur. Should I just leave the drives tucked when I'm going to be flying? With the standard lengths, I wouldn't hardly run over 40 with the drives tucked...but it seems that now it will. Or, is it just that I've got to develop a better feel for how I'm throttling now that I'm dealing with a WHOLE lot more torque?

Any advice would be appreciated.
mike
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Old 06-12-2011, 10:38 PM
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Are you not pulling out of the throttles at all? Or are you saying that when you land and hit the throttles they blow out?
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Old 06-13-2011, 05:49 AM
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I'm pulling back when I leave the water and returning the throttles to their previous position upon re-entry. Consistent rpms being the key...
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Old 06-13-2011, 06:03 AM
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Your just pulling back too far. You only want to pull back enough to keep your prop speed the same as your boat speed. that way when the props go in/out of the water is isn't loading/unloading your drives.
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Old 06-13-2011, 11:12 AM
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We were out with Donzi's race driver several years ago who seemed to be back on the throttles just before the drives re-entered the water. My impression was that he was making an effort to keep the nose up upon re-entry and keep the momentum going. He certainly wasn't waiting to get back on the throttles, which surprised me at the time but I guess this is the way to do it. My impression is that some people loose too much momentum and risk stuffing by pulling back too far and not getting back in the throttles early enough. I’m certainly not an expert, but are my impressions correct?

I'd probably leave the drives out and try to work on the throttles to find a solution.

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Old 06-13-2011, 11:28 AM
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They shouldnt blow out. Its nothing you are doing. Play with the set up until they don't blow out. Maybe a bigger diameter prop. Good luck! You should be able to hammer it on reentry and hook up.
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Old 06-13-2011, 11:40 AM
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Originally Posted by FREEDOM US1 View Post
They shouldnt blow out. Its nothing you are doing. Play with the set up until they don't blow out. Maybe a bigger diameter prop. Good luck! You should be able to hammer it on reentry and hook up.
Thanks Jim. I'm hoping I didn't lose my touch over the winter!
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Old 06-13-2011, 12:31 PM
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You might need to add a 1" spacer to bring the drives back down a little.
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Old 06-13-2011, 01:10 PM
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Quote:
Originally Posted by sommerfliesby View Post
Here's the situation: I've got a single-step 35 Reggiecraft Any advice would be appreciated.
mike
My Advice is ...Cigarette

Not sure what you are running for props but if not 5 blades may give them a whirl, then as Griff said 1" spacer.
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Old 06-13-2011, 02:33 PM
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[QUOTE=Von Bongo;3428013]My Advice is ...Cigarette

QUOTE]

You first bro! We'll be at LOTO for the 4th if you guys are around...
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