kreed

iTrader: (2)

As most know I bought Craigs(Old School) infamous 1988 Top Gun a month ago. Not sure who the legend is here, the boat or the owner! Hahaha, but they are both pretty damn cool. Anyway, as the boat sits now, I believe the prop shaft is about 1" below the bottom of the boat. Presently running wet sump #6's and 16.5 X 29P props with approx.750 a side the boat runs mid 80's with a light load...... In talking to a few people, they thought there was a lot of speed being left on the table with the prop being so low. It is a notched transom and its also a Kevlar hull. The boat will have a fresh set of N/A 800 HP a side next year. So my question is, where should the prop be in relationship to the bottom to get the best speed out of the boat without needing 5 blade props to get on plane. I don't mind winding it up a bit to get on plane, but cant afford 8 to 10K for props. I have a set of 17X31's Id like to use if possible. I know there is probably some info on this subject somewhere on OSO, but Im looking forward to an informative and fun thread.... Any and all comments or advice will be appreciated.

1MOSES1

Unlimited jd

iTrader: (5)

Up 2.....lol

OldSchool

I'm sure that all of the keyboard experts (whether they own a boat or not) will come out on this one!!!!

What you have to remember is that... of the 12 or so straight-bottom TG's, only one or two came that way from the factory (D-Man's is the only one that I can think of now and he spent a chitload of time trying to get it right). Like I said in the other thread, be careful about phucking around with something as an experiment that is OK now. ..... or just take your time getting used to it. It's a different animal and isn't easy to drive. But.... Once you get a feel for it, which will take some seat time, you'll love it.

Talk with Tres Martin ....and it'll be interesting if Steve (Cignificant Other) chimes in. He spent some time researching this as well. It might be more helpful for you to get good advice to explain what you are trying to do with the boat. Race it? Use it for pleasure only? Run hard all of the time, etc???

OldSchool

Also, keep in mind that the #6's on that boat have 1.62 gears in them. With the 1200's, I was running 16.5 X 33's @ 6200

Zero Patience

Mine has dry sump 6a, 1.25 inches above the bottom. 17 x 32 x 18r, 5 blades. The 17 diameter is not enough, going to buy more of those too expensive props. 17.75 inch diameter this time. Plane off is easy. Just to much slip in midrange. I ran some 17.5s and the cruise picked up 10 mph. Propping these is the worst part, there are so many choices. Mine did not like 4 blades in 17 diameter, but maybe 18s would have worked. 1.5 gears in the drives.

88bullet

iTrader: (1)

Ive learned over the years if you want something fast buy something fast. don't buy something Big heavy and slow and try to make it fast. In the end it just doesn't work out. But in your case with 750's and in the 80's whats wrong with that? At least you know your not gonna splatter a bravo driving through whatever you want.

TxHawk

iTrader: (2)

I can't imagine considering moving drives on a dry boat for 50HP a side.

Unlimited jd

iTrader: (5)

What's wrong with trying to get the most out of it? The best part about going up is you can space down fairly easily and find the perfect spot. My feeling is there is 3-5 mph left on the table with its current setup.

kvogt

If the boat was running over 100 then maybe there is 3-5 left on the table, but at mid 80s I would guess less than 1 mph.

Spend your money on props, they are expensive but will give you the best all around solution.