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3.5CC OR 7.5CC OUTBOARD???

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Old 11-16-2008, 06:31 PM
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eengler
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Default 3.5CC OR 7.5CC OUTBOARD???

Ok guys straight to the questions, should I spend my money on a "new" K/B 7.5CC outboard to reach between 38-44mph on a tunnel or buy an O.S to reach, I don't know what speed?? I would be more inclined to "slight modify myself" the 7.5 cc. Who is James at O.E.R? does the sell "new" modified O.S engines? It would be nice to see a wood 24 inch dumas or a VS1 with a "factory modified" O.S 0.21..... ( currently I have a TS2 with a slightly modified (just sleeve and crankshaft) regular k/b 3.5 cc and it will do 35mph all day, i love it, super reliable). Just looking for a second toy....
Old 11-16-2008, 08:29 PM
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Jerry Dunlap
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

First the "Disclaimer:" I am a consultant for AquaCraft.

Yesterday, I tested the recently released AQ VS1 3.5 tunnel hull with an stock O.S. 20 OB. It was easily doing 45 mph in a small pond. You don't need a modified O.S. 20 to run close to 50 with the right boat.

JD
Old 11-16-2008, 08:54 PM
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eengler
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

hmmm sounds good, on a 0.21 size engine it's not that easy to reach 45mph. What nitro and prop where you using? Thanks.
Old 11-16-2008, 11:46 PM
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Ron Olson
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

OK, what's you're ulterior motive? Any plans of racing? If so, I'd stay with a .21 OB tunnel as the .45/7.5 class is slowly dying off for lack of engines.
The VS-1 isn't really made for a modded engine. You'll have to wait to see if Mike and the crew at Aquacraft are going to come out with his Nemesis for that.
Old 11-17-2008, 01:35 AM
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Jerry Dunlap
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Default RE: 3.5CC OR 7.5CC OUTBOARD???


ORIGINAL: eengler

hmmm sounds good, on a 0.21 size engine it's not that easy to reach 45mph. What nitro and prop where you using? Thanks.
Nitro was 50% O'Donnell. Prop was a backcut Octura 1440 from Joe Monahan at 707 Specialities.

JD
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Old 11-17-2008, 06:23 PM
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eengler
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

Thanks Jerry, mind telling me where i can find 707 specialties? Sounds like a preety easy setup to reach over 40mph. Thank You. I'll be happy with anything over 40mph consitent! "not falling off pipe" etc.... The ts2 with the stock k/b is just not competitive in the 0.21 class.
Old 11-17-2008, 08:03 PM
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Jerry Dunlap
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Default RE: 3.5CC OR 7.5CC OUTBOARD???


ORIGINAL: eengler

Thanks Jerry, mind telling me where i can find 707 specialties? Sounds like a preety easy setup to reach over 40mph. Thank You. I'll be happy with anything over 40mph consitent! "not falling off pipe" etc.... The ts2 with the stock k/b is just not competitive in the 0.21 class.
Joe Monohan (909)584-1638 Tell Joe you'd like a 1440 like he made for JD.

JD
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Old 11-17-2008, 11:44 PM
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

Here's Joe's site: http://home.earthlink.net/~namba707spec/
Old 11-20-2008, 10:59 PM
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eengler
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

Thanks Jerry, I ordered a VS1, O.S engine and a prop from Joe. Please help me set up the boat similar to yours, I have "heard" that i have to remove the head shim from the O.S. engine? Thanks! And just advise me on anything else that comes to mind.
Old 11-21-2008, 04:00 AM
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

So is 7.5cc really dying. I was thinking of cruising ebay for a K&B 7.5cc pro outboard or maybe stepping up to a new Rossi 7.5cc, but if its a dyin... I just like to mess with these things but I don't want to be in the slow lane. My hull is also old fashioned so it might be better to try anew with another combo.
FM
Old 12-06-2008, 11:45 PM
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Default RE: 3.5CC OR 7.5CC OUTBOARD???

It's not dead where I race...Just hibernating for the winter!
Larry

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