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1979 Viper
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Author:  CoveSlinger [ August 9th, 2016, 11:53 am ]
Post subject:  1979 Viper

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Author:  tunnelv [ August 9th, 2016, 1:11 pm ]
Post subject:  Re: 1979 Viper

Very Nice!!

Author:  CoveSlinger [ August 9th, 2016, 3:09 pm ]
Post subject:  Re: 1979 Viper

Thanks! I've been working on setup:

- Prop shaft 3'' below pad (no low water pickup yet)
- 28p Chopper 73mph @ 5200

Between 25mph and 50mph boat porpoises like crazy which I understand is common?

60+ can take very minimal trim but seems to fly on the pad nicely.

I've been told a cleaver is the way to go? Maybe a 26p?

Author:  13Checkmate [ August 9th, 2016, 4:25 pm ]
Post subject:  Re: 1979 Viper

Sweet viper! Is that the one off kijiji that was rigged for merc? Tap your water pickups and locktite in some set screws. Jack up the motor another inch or two and try a 28 cleaver or your chopper but watch the trim. That should get the revs up a bit as would the speed. If you need a cone installed, I install, shape and paint them.

Author:  CoveSlinger [ August 9th, 2016, 4:46 pm ]
Post subject:  Re: 1979 Viper

Yes, that's the one!

I haven't decided if I want to keep this motor on it or switch to something lighter for better all around performance. The porpoise is hard to deal with when you just want to cruise. I guess I could add some weight in the bow?

I have a water pressure gauge and I'm ok at the moment. I'm going to try and go up an inch at a time and see what happens. Not familiar with tapping and adding set screws, what will that accomplish?

Author:  13Checkmate [ August 9th, 2016, 6:29 pm ]
Post subject:  Re: 1979 Viper

Not sure about adding weight to a viper as i havent owned one, but based off the way my cousins 15 check bounces it wouldnt hurt. Id probably start with putting a 3 gallon fuel cell up front. Now tapping the pick ups and blocking a few holes would let you try get the motor up higher without losing pressure or needing a cone. It atleast lets you try get more out of it before commiting to a nose cone

Author:  Hydroid [ August 9th, 2016, 9:02 pm ]
Post subject:  Re: 1979 Viper

As you raise motor it is likely top of water intake will be above surface, no water pressure; the water entering lower part of intake is likely to exit top of intake which is aired out rather than pressure pushing water up pipe to engine for cooling. No cooling water, screech, kaboom.
13Check is giving you great advice to plug top third or half of intake if you're going higher. I like tap/set screw recommendation.
Most T850 racers plug top 2 of 4 Nitro case intake holes on either side of case to allow us to jack engine safely to maintain colling water pressure; a water pressure/temp gauge or pisser tube also recommended.

Author:  idvette [ August 9th, 2016, 9:57 pm ]
Post subject:  Re: 1979 Viper

As far as the porpoise goes getting the motor up will help, as will a drag plate. Try out a few different prop designs. But just "cruising" in a small V6 powered boat will be tough. I found my comfortable cruising speed around 60mph.

Author:  CoveSlinger [ August 10th, 2016, 10:52 am ]
Post subject:  Re: 1979 Viper

Thanks for the advice everybody. I`ll keep tinkering.

Author:  beavertonae-21 [ August 10th, 2016, 12:26 pm ]
Post subject:  Re: 1979 Viper

Nice ride!!!!! Man , does that look clean.

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