Speed Gains f0r 2011: What did you do?

Went from tired stock 502 EFIs to fresh 540 CU mills with 570 hp apiece and 622 ft/lbs of torque. Speed was 75mph...new speed is t.b.d....this weekend. Also added -2 lowers on the drives...

Trying 30 Bravos to start....
 
Went from tired stock 502 EFIs to fresh 540 CU mills with 570 hp apiece and 622 ft/lbs of torque. Speed was 75mph...new speed is t.b.d....this weekend. Also added -2 lowers on the drives...

Trying 30 Bravos to start....

My Phantom had 502/415, went to 540 Darts, kept the 502/415 efi top end and cylinder heads. You will like your improvement(s). The mystery piece is raising the drives 2", wonder what the gain from added drive height is. Let us know how it ran.
 
Rebuilt engine, went from 71 to 85 and still prop testing
 

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Thanks went from stock 320 hp to 600 hp should run out at just north 90 when I get it propped right, it's off the chain fun in an 18 foot boat ;)

That is great. I had an 18' Donzi, loved the boat. There used to be a blue X18 Donzi with a SBC blown and arneson drive that ran strong (over 100 mph), never met the owner who put it together (George Desomd), but alwasy thought of making an 18' Donzi ran anywhere 80 mph is ballsy, and a cool boat. I like what you are doing with your boat!

Keep us informed on how the prop testing goes. Cool performance upgrade.
 
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That is great. I had an 18' Donzi, loved the boat. There used to be a blue X18 Donzi with a SBC blown and arneson drive that ran strong (over 100 mph), never met the owner who put it together (George Desomd), but alwasy thought of making an 18' Donzi ran anywhere 80 mph is ballsy, and a cool boat. I like what you are doing with your boat!

Keep us informed on how the prop testing goes. Cool performance upgrade.


That was Geoo's boat ran like 123 mph had a procharged SBC was like 1000 hp crazy sick boat!!

I should be able to find another 5-7 mph I believe :) 90 was the end goal.
 
thanks Will and Paul ,,,but you will have to get an up and close look ,, to see all the changes,, it truly will amaze you of the simple hull and deck changes,,and a zero drag theroy,,it,s simple and it works,,,see ya all in Sarasota,,
 
thanks Will and Paul ,,,but you will have to get an up and close look ,, to see all the changes,, it truly will amaze you of the simple hull and deck changes,,and a zero drag theroy,,it,s simple and it works,,,see ya all in Sarasota,,

Specifically tell us what changes you made to reduce aero-drag? You have my interest that is for, help me learn a thing or two.
 
I lost some weight, quit drinking Heinies. Gained about .00015 MPH. Just kidding.
Did some prop testing, dinoed, got 580 & 581 horsies out, knowing the motors were OK, I wasn't afraid to "push it" with some trimming out, running props out, instead of "in", we had a great run in Jax. Last once out of the docks, we got to the upper 1/3 by the bridge in dish washing type chit of waters. THe Avanti loves that rough stuff. :)
 
Smarty ,,we added a Bussell to the transom ,to reduce the vacume at the back of the boat,,,i useto have a real tall scoop ( about 14'' high) ,,and as you can see ,i went to the hydro ,cabover 5'' ,,their are also a hand few of things ,i,v done to the deck and hull that will come out after everyone sees it at the first race,,SARASOTA !!
 

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thanks Gris,,,i,m dying to come out to Texas with her ,when you guys have the big tie-up party,,,:cheers2::cheers2::cheers2:
 
Smarty ,,we added a Bussell to the transom ,to reduce the vacume at the back of the boat,,,i useto have a real tall scoop ( about 14'' high) ,,and as you can see ,i went to the hydro ,cabover 5'' ,,their are also a hand few of things ,i,v done to the deck and hull that will come out after everyone sees it at the first race,,SARASOTA !!

Wont a bussell create more negative drag at the transom since the airflow is sucking it out from under it? I think a rolled down deck to transom is the best to advance the airflow and not to have drag at this point ???!!

Now with the airscoop, wouldn't it be better to have one that does not force air in and have it sucked in as needed (like 1 or 2 small ones turned reverse on the hatch) ?

I think forced air is always like a parrasute effect no matter how much holes u have to let it out..hhhhhmmmm:confused:

But it looks good, like always !:seeya:
 
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