looking for HP/speed info
 

hello everyone.. as you know from the other thread i bought Jays Kryptonite. i was wondering how fast these boats go with different power and setups.

i set the carb with a wideband and set the timing and got from 87 to 89 with 3 people and 3/4 tank of fuel.

548 cu 650hp 5700 rpm 37 deg timing 12.9 afr XR lower 28P bravo1 89mph.

http://i27.photobucket.com/albums/c1...0046941683.jpg

Ray,
What the hell is that in the exhaust pipe?

Mine supposedly had 800hp when i bought it in 08. I ran a best of 102mph with it, but the PO said he had seen 106mph. Dont know where that extra 4mph was hiding, but I never found it.

After the rebuild I have seen a best GPS speed of 97.5mph. Non dynoed and not even really dialed in with either the carb or the prop. I am guessing that I am around 725hp. I have probably gone faster with a different prop that I broke, but my GPS speedo wasnt working all summer so I can not verify that. I am installing A/F sensor and EGT bungs as we speak, so the engine will be dialed in this summer.

They seem to run right around 90 with about 625hp, Powerboat tested one with a stock 525efi at just over 80mph.

You will pick up a ton of speed just by getting some people out of the boat. I pick up a solid 4-5mph from a full tank to an empty tank.

thats a wideband sensor. i ran it for that day to set up the carb

wow thats a big difference in speed with less fuel. ive only been out a few times so far. i wanted to get it set up just right so i dont mess with it once the weather gets nice.

my friend Ron who had the insanity boat was running 100 with 740ish hp (i dynoed it myself but i dont remember exactly) he also had a standoff box and imco shorty lower.. not sure how much difference that makes.

im not new to big block chevys or boats like this in general. i am new to owning a fast big block boat. i was running a hydrostream that ran 90s. what a different world! you can fall asleep running 90 in this boat haha

with 775 hp 104 mph with steel heads - updated to dart pro ones aluminum heads made 834. never got on it.

Yeah, it picks up a ton of speed with less weight in the boat.

I am pretty confident that I will run over 100mph with ease this summer. my headers are on their way back from CMI as we speak. I had to get some "water injection" cracks repaired and while they were there I had them weld in two EGT bungs and two A/F sensor bungs. I was running very rich all summer in the heat, I picked up a few mph just running in 60º weather in October.

I would say that if he ran 100 with 740hp, my guess of 725 or so should be pretty close. I have a -1 imco shortie and an ITS box, which gives about 8" of setback. I am just over 3" below the pad and would like to go shorter. DonRoc set his up with a -3 Imco and redid his transom, resulting in a setup where he was right at 1 inch below the pad with a notch and and ITS box. He ran 90.1 with an estimated 600hp. who knows how fast his boat would have gone with the 1275hp that he had in it.

id love to get my boat to 100 one day. id like to give a shorty imco a try too. how much do these boats weigh?.. rigged with no fuel etc

My boat with a full tank, helmets and lifejackets was 5100 lbs

That sounds about right. No people in it right?

So that would mean a 4500lb dry weight, give or take, considering 100gal of fuel at 6lb/gal.

No people in it and we only have a 60 gal tank