Scary fast (for me anyway)
 

OK i am ready to get chewed out but i just wanted to express my thanks to the board. Last night i had my boat up to 94 on gps and i was at 5200 rpm and plenty of stick left. I am not going to go this fast again until I get external steering on it. And.... next time, helmets.... It honestly felt great and it was effortless. it felt like driving a car at 75 mph on the interstate. The motor has about 6 hours on it and i have broke so many little 300 dollar items i am scared to push it to its 6,000 rpm limit. I am none the less a very happy camper :D :evilb: :D :evilb:

I am thinking that the prop that i have must be tweaked or my tach is off. At this speed and rpm i am getting 7 % slip which is really hard to achieve?!?!?! I am thinking that the prop is probably closer to a 28 pitch even though it says 27 on it. This puts slip at 9% which seems more realistic. It has a ding or two in it and seems shaved a bit. But it is in overall decent shape. How much can you tweak these props/stretch pitch? It is a mirage 3 blade on a twin step Eagle. Are these realistic numbers? What is a reasonable amount of slip to expect? i had about 30 gal of fuel on board and two people......

Re: Scary fast (for me anyway)
 

SWEET!!! Definatly get the steering at those speeds!! :eek: :D Helmets, neck braces and Lifelines also. You should get an on board video at that speed :cool:

Re: Scary fast (for me anyway)
 

i wouldnt run over 80 with out external steering...NOWAY.

Re: Scary fast (for me anyway)
 

Extermal steering is a must, I've heard its recommended on anything that does over 70. I could asume it could get pretty messy if something were to break at those speeds. Thats movin out though keep it safe!!

Re: Scary fast (for me anyway)
 

Your numbers seems off. Are you running a 1.36 drive? Even if you are I come up with 4% with the 27 pitch and 7% with the 28 pitch. Those kind of slip numbers are about impossible with a single engine 28' boat. If you are running a 1.50 drive you are at a neg. slip.(that's not at all possible) What kind of Hp are you running? Are you sure your tach and GPS are funtioning properly?
I run closer to 14% with a single engine 30' er and a stepped hull. 4% and 7% seems impossible.

Re: Scary fast (for me anyway)
 

that is what i am saying about the slip numbers.... i am running a 236 eagle. with DD 2003 numbers of 540 CID 713 hp?????? This is a estimation, The boat from Eliminator weighs 3400 with a merc 330 hp( mine has aluminum heads and intake and exhaust)Yes the drive is 1.36. I was running downstream but at a area of the river where it is really slow and wide(maybe 2 mph more like 1 mph). We had a beer or two and i did not want to go that fast again without the proper safety equipment/steering.

Re: Scary fast (for me anyway)
 

Who cares about slip numbers? That puppy is hauling ass! :drink:

Re: Scary fast (for me anyway)
 

I'm with Cuda....Haulin' AZZ.....who cares about slip at that speed!!! :eek: :D If you can go fast enough to suck the beer out of your can....Thats fast enough for me!!

I've flown out of a boat at 80 w/o safety equipment on and when I woke up 4 days later....it still HURTS!!! :p Get the 'quipment for the next run!! :D

Re: Scary fast (for me anyway)
 

Yep Yep.... I am recovering from a car accident where i got ejected. I broke 9 bones....It still hurts. I have to get the right stuff to do that again. besides it is nice to know you an go that fast.... and when some one asks how fast dose it go you can say I DON'T KNOW. I had it up to 94 with some stick left :drink:

Re: Scary fast (for me anyway)
 

Very nice performance from a single engine vee! Definately get steering and at least a lifeline poker run jacket. Choose your water wisely! As for your slip #'s 10% on a vee is almost unheard of. Normally 15% is in the ballpark. My 23' cat runs at about 12%. Check your tach and have fun!!!

Craig

Re: Scary fast (for me anyway)
 

I am wondering if the calculation we are presently using is correct.
Are these GPS speeds believable?
I ran a Bravo 26, just reconditioned by ThrottleUp, and was seeing, on GPS, 82.7@5600 rpm.
This is a 1989 27' Activator with a 1.5/XR/IMCO -2 Shortie drive, 5.25" propshaft to keel dimension.
I questioned the pitch number back to Julie and she said that they put it back to stock, which is a measured 25" of pitch for a Bravo 26. She thought my tach could be off.
I have yet to confirm it's accuracy.
If you crunch the numbers and use 26 for the pitch, it calculates out to 10% slip. At this point, it's anyones guess.
Russ

Re: Scary fast (for me anyway)
 

Can I borrow YOUR gps??

Those are incredible numbers.

Re: Scary fast (for me anyway)
 

lets say that the water down stream was 4 mph.... so this puts me at 90 mph.... this could account for the really low slip numbers. i have also had it at 70 with 7 people in it and the rpms were much higher like 5400 (closer to 20% slip) but i did not feel comfortable with that many people in the boat going fast. Once again i do not know how the guys with the big cigs and cats do it? so it is possible for the prop be more to a 28 that a 27 as stated. but if you shave some off the leading edge to increase rpm..... Hell i do not know.... i should just drop the boat off at Bblades in Princeton, and have him work me up a prop. This prop slip thing is interesting. so much technology in a prop.

Re: Scary fast (for me anyway)
 

This prop slip thing is fun but to really dial it in i have to get the steering. and other things. i think i will just let it go for this year and enjoy the boat. it goes too fast to dial it with the equipment that i have and i do not want to hurt my self or any one else. How much for a prop recondition and dial in? this 27 that i have seems close to what will work.

Re: Scary fast (for me anyway)
 

what online prop calculators are there out there?
I was using bams go fast knowlege base one. Do they all go off of the same figures?