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Discussion Starter #1 (Edited)
I have a 496 bbc with two 1050 dominators sitting sideways on a tunnel ram. The engine makes 800hp, and I'm using a Clay Smith 140gph mechanical pump, and the pressure is set at 7.5#. Here's my problem, the boat launches hard then lays down then accelerates again. I was told that the side mounted copper floats I have may be causing the problem by cutting off the fuel at the launch. It was suggested that I change to center mounted floats, the black notched ones. What do you think?
 

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I run the notched floats. Helps the float level in ass heavy boats.
 

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I have a 496 bbc with two 1050 dominators sitting sideways on a tunnel ram. The engine makes 800hp, and I'm using a Clay Smith 140gph mechanical pump, and the pressure is set at 7.5#. Here's my problem, the boat launches hard then lays down then accelerates again. I was told that the copper floats I have may be causing the problem by cutting off the fuel at the launch. It was suggested that I change the floats to the black notched ones. What do you think?
Do you have a fuel log , or just lines and a T? With no log and by-pass regulator you could be running the lines dry.
 

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Discussion Starter #6
Do you have a fuel log , or just lines and a T? With no log and by-pass regulator you could be running the lines dry.
No fuel log. I just have -6 hoses from the Product Engineering fuel regulator to each bowl. The regulator is a by-pass but I have the return plugged. Could it still be causing the fuel shortage?
 

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Discussion Starter #11
Okay, I think I'm missing something here. Yes, my carbs are mounted sideways. Are the center mounted floats not for sideways mounted carbs, or is it the extensions? I'm just trying to understand....
 

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When I bought my jet extensions and notched floats it was for a different reason than why you did/are. I bought them for the back bowl of my holly. (carb mounted fwd.). Like I said Sorry....nevermind
 

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Now I'm lost. I was talking about the roundy round floats not the ones for the jet extensions.
 

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Discussion Starter #14
Yeah, I'm getting lost too! All I really wanted to know is if the black notched, or non-notched floats, that are center mounted will prevent the float from shuting off fuel when my boat launches. The current brass floats are side mounted and with the carbs being mounted sideways "I think" they are shuting the fuel off as the gas surges to the rear under a launch. I don't know if there is any advantage in having jet extensions? Additionally, I wonder if my pluging the bypass port on my regualator may be causing the problem, maybe flooding the engine? Any help or suggestions are greatly appreciated.
 

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No fuel log. I just have -6 hoses from the Product Engineering fuel regulator to each bowl. The regulator is a by-pass but I have the return plugged. Could it still be causing the fuel shortage?
A fuel log is / was a must for me........... runs the lines dry with a mechanical pump, need the fuel volume stored after the fuel pump' also helps immensly flaming in rough water.
 

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A fuel log is / was a must for me........... runs the lines dry with a mechanical pump, need the fuel volume stored after the fuel pump' also helps immensly flaming in rough water.
A mallory 3160 filter will work, between your tank and fuel pump and you can run your return back to the filter........... otherwise a mechanical pump will cavitate if you don't plumb the return correctly................
 

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Yeah, I'm getting lost too! All I really wanted to know is if the black notched, or non-notched floats, that are center mounted will prevent the float from shuting off fuel when my boat launches. The current brass floats are side mounted and with the carbs being mounted sideways "I think" they are shuting the fuel off as the gas surges to the rear under a launch. I don't know if there is any advantage in having jet extensions? Additionally, I wonder if my pluging the bypass port on my regualator may be causing the problem, maybe flooding the engine? Any help or suggestions are greatly appreciated.
You shouldnt plug that bypass. That thing needs to bleed off. Side mounted floats on side mounted carbs = bad.
 

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I dont think jet extensions and the corresponding notched floats are what you need. Those would come into play under acceleration with the bowls fore and aft.

If you carbs are mounted sideways, upon acceleration the fuel rushes aft (to the side of the float bowl in this case) and raises the float, closing it prematurely. Braswell and Holley make floats that have one or both undersides cut at an angle so the gas just rushes by without lifting the float up. They redesign the weight in the center so the float maintains the correct overall weight.

Braswell does not cost any more than Holley, and their quality is the best. For example, the metal pieces are stainless steel, where Holley uses cad plated god-knows-what. If you call the guys at Braswell and share your setup info, they will help you get the correct parts.

They also make a variety of different strength float rebound springs to steady the float...again out of stainless steel. Hope this helps.
 

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Regarding a Fuel Log

I dont use a fuel log either, but I do run #10 line all the way to the regulator. Beyond that, things that help are internally radiused nipples, and radiused bend fittings, never 90's. An inline filter, like a System1, and you should be good. You have a great pump.
 
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