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i am constantly asked how much HP my SBC puts out or whats inside of it. Since my dad had it built no way to answer the second question however now that i got some numbers on the boat hopefully some of you smart mofo's can throw me some ballparks...



350CID spins a B impeller at 5000K up to 60 MPH..

Im damn proud of that number since i was assured she would not see over 35 mph :)grn.

 

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350CID spins a B impeller at 5000K up to 60 MPH..

Im damn proud of that number since i was assured she would not see over 35 mph :)grn.

I heard the same story. "small block dont make enough torque" and other such nonsense.

Small block maybe dont make enough horsepower, but in a light boat the weight can be an advantage in holeshot and economy. It definately is an advantage in price (well except if you got to build three of them to finally find out how to make the horsepower:)sphss).

Now you should be able to put a 100 shot on that bad boy and it will really wake up (70mph). Most SBC will absorb 100 shot with just a little attention:
Cool plugs (j gapped, no extended tip), fuel pressure switch, WOT switch and start with -2deg timing. Take it slow and read the plugs. It is better to have built it with the nitrous in mind (cylinder bore, ring gap, quench)

oh yeah they stay together (so far) and you can run the dogshit outta them.
 

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I'm calling bullsh!t on that one. 100 HP = 10 mph - I don't think so.

:(:( :D


typical torque BBC response...that along with you cant do 90mph on 550 hp.



Supersoaker turn an [email protected], [email protected] for me is 70mph and we have done hundreds of miles at these speeds. The higher speeds seem to be hit and miss at around 90 for the same horsepower...even the same day just minutes apart...on 87/89octane.


Depending on what boat Delemorte's is, he can get near 70 with his existing horsepower. The tunnel is somewhat more efficient...nevertheless.. Its all in setup.

It is true that the 70mph is the calculated mph based on 60mph with 340hp ([email protected]) and this puts his 440hp rpm at 5460.

And it is true that 70 is not guaranteed...There can be problems in the intake/setup/hull that can start to show as the speeds go up, including severe porpous, pump vacation, set and other things...

I think he can get over 70 with a little setup and 100shot...easy.


sbc cant do 90

Mouse Reeks Havoc

Oh, yeah i get 4mpg average, fixed nozzle, and no porpous and ANY speed guess you dont believe that either.
 

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typical torque BBC response...that along with you cant do 90mph on 550 hp.



Supersoaker turn an [email protected], [email protected] for me is 70mph and we have done hundreds of miles at these speeds. The higher speeds seem to be hit and miss at around 90 for the same horsepower...even the same day just minutes apart...on 87/89octane.


Depending on what boat Delemorte's is, he can get near 70 with his existing horsepower. The tunnel is somewhat more efficient...nevertheless.. Its all in setup.

It is true that the 70mph is the calculated mph based on 60mph with 340hp ([email protected]) and this puts his 440hp rpm at 5460.

And it is true that 70 is not guaranteed...There can be problems in the intake/setup/hull that can start to show as the speeds go up, including severe porpous, pump vacation, set and other things...

I think he can get over 70 with a little setup and 100shot...easy.


sbc cant do 90

Mouse Reeks Havoc

Oh, yeah i get 4mpg average, fixed nozzle, and no porpous and ANY speed guess you dont believe that either.
I watched your video and your boat runs good. But dont trust that stupid peedo tube speedo. You can do all kinds of thing to them to read high #'s. I have done it. Lets see some gps speed runs. I also noticed that your cruising at about 34-3600 rpm and doing 70 mph on your speedo.. That right there tells me your speedo is jacked! Nice boat BTW, but your loosing alot on the holeshot with that giant wheelstand.

Cool ride none the less.
 

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I watched your video and your boat runs good. But dont trust that stupid peedo tube speedo. You can do all kinds of thing to them to read high #'s. I have done it. Lets see some gps speed runs. I also noticed that your cruising at about 34-3600 rpm and doing 70 mph on your speedo.. That right there tells me your speedo is jacked! Nice boat BTW, but your loosing alot on the holeshot with that giant wheelstand.

Cool ride none the less.
I take these videos at 30p HDV that is 30 1440x1080 pics per second.

the tach is not visible on any of the parts of the video shown such that you can tell what the RPM is...neither is the speed constant enough to tell what speed is what speed at what rpm. The speedo is as accurate as one can expect out of one of them.

Dead nuts at 50, off by 3mph at 80 (i think Supersoaker told me his was off by two) both high


When we run side by side, for any real distance, our gps reads the same, and the pitots are always off by about the same (we run in salt water too, makes them off a little different).

Upon very rapid acceleration/deceleration my gps just cant keep up. Donnie says his can.


and i have never been able to position the tube, or get something stuck in the tube, or change the face of the tube that makes it read high....always low (so far)


I cant find how to calibrate the speedo either...there are marks at 70 and 73...i believe they mean 70psi in fresh and salt water. I have thought about just using a pressure transducer, and doing the conversion. I use this pickup.


and with GPS you got to subtract (or add) the river speed


........


Now about the bow rize....yes it pushes the boat entirely out of the water and only about 450 hp can be sustained for the first 60 feet or so or it will vacate the pump. What can i do? Jump on the front if it and hang my legs off the end like i use to do on the bikes? Or do you suggest more throttle control?

I have thought of putting sheets of aluminum shaped like the tunnels behind the tunnels...sort of a trim tabby thing. Then i could run to cavitation.

Thank you for the compliments too.


Well... can Delemorte get 70 with a 100shot?
 

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When someone asks that look them square in the eye and say "I don't have a clue how much horsepower this thing has". Problem solved.

If people are asking you that you are really pretty lucky. Usually the number one question out of the typical person is "how fast does that thing go?"
I used to wish they would ask how much horsepower I had.
 

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Now about the bow rize....yes it pushes the boat entirely out of the water and only about 450 hp can be sustained for the first 60 feet or so or it will vacate the pump. What can i do? Jump on the front if it and hang my legs off the end like i use to do on the bikes? Or do you suggest more throttle control?

I have thought of putting sheets of aluminum shaped like the tunnels behind the tunnels...sort of a trim tabby thing. Then i could run to cavitation.

Thank you for the compliments too.
Try using a place diverter. Put the nozzle down when your on the launch and then trim up after your boat takes a set. Thats how i drive mine now. I had a fixed nozzle and where it was set for the big end made the holeshot shit and jumped out of the water..
 

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That's smart, going over 80 with a video camera in hand recording :)sphss
you dont look thru or at the camera. Not even the gauges...just the river. Gotta wait till you get back home to see what you got.
 

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Try using a place diverter. Put the nozzle down when your on the launch and then trim up after your boat takes a set. Thats how i drive mine now. I had a fixed nozzle and where it was set for the big end made the holeshot shit and jumped out of the water..
no place diverter for me...i worked long and hard to get this boat to handle all types of water at any speed with no "gee i wish i had a place diverter"

yes, a diverter would help in this situation. I dont plan to get myself in that situation any more. More interesting than a video of the (at that accelerration) meaningless GPS is what the oil pressure does...scary. Took a while to get that better too.

So... can he get 70 with 100 shot or not?
 
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