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 Post Posted: Mon Aug 15, 2011 8:59 pm 
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Hello all,

Had my float bowls off today and I noticed that the accelerator pump check valve end that sticks up into the float bowl seems to be preventing the float from dropping all the way. Just looking at it, it seems to be preventing over half the travel. I haven't noticed anything out of the normal with the exception that the car seems to lean up about about .5 afr from the start to the end of the run. Although I attributed it to needing a little less HSAB. But if the floats were not dropping enough to allow enough fuel flow and the fuel evel slowly drops throughout the run, wouldn't this cause it to lean up? I will be sniping them when I put it back together, just curious if anyone has seen this.

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 Post Posted: Mon Aug 15, 2011 9:37 pm 
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I clip mine just above the bulge that keeps it from falling into the pump body. Not enough float drop could cause some issues for sure so you may not need to change those MABs after all, hey.

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 Post Posted: Tue Aug 16, 2011 9:23 am 
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It is interesting how little stuff like that can potential effect stuff.

I am also doing some further experimentation in my quest accelerator pump leaning. I have found that I have gotten to the point modifing the cams, that it becomes very finicky as I modify them. I was looking at the braswel bowls and it says they have a accelerator pump bleed off jet option. Got me thinking so I have installed one on my current float bowls to if it will help me to lean out the end of the shot like I want. Thinking about it, it seems like it would be a much more effective way to tailer the pump shot.

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 Post Posted: Tue Aug 16, 2011 9:30 am 
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Bill in my previous post, I forgot to mention that the only reason for that long tail on the pump check valve is there to allow you to pull the bulge through the hole.

Bleeding off the pump shot sounds like a good option. Where did you put that and what did you use? :-k That sounds like a much easier way to reduce the pump shot than messing with cams. :-k

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 Post Posted: Tue Aug 16, 2011 9:43 am 
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I will take some pictures tonight,

I put it in the accelerator pump boss, just outside the pump check valve, that way it will bleed directly into the fuel bowl and always stay covered with fuel. I had originally though about putting one in the metering block, but I was concerned that it may bleed fuel out of the circuit and caused issues so I decided to make it a seperate circuit. I used a 10-32 bleed. When I read that option about the bleed, it really got me thinking. It thinking like this that makes braswell one of the top carb builders. Its very simple, yet very innovative. It should provide another level of tunability. It kinda of cool to see that they also saw the issue that I saw with the pump volume and came up with IMO alot better way to remedy and tune it. I think I will be going back to the original dominator cam so I can keep the accelerator cam profile. I will be testing this weekend with this setup.

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 Post Posted: Tue Aug 16, 2011 6:58 pm 
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Here is what I did

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 Post Posted: Tue Aug 16, 2011 7:33 pm 
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I'm anxious to see how this works out!! If it does like we think, then I'll make a "sticky out of it to add it to the top of this section with the other carb mods.

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 Post Posted: Tue Aug 16, 2011 7:47 pm 
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I just bought some white pump cams for a Dominator, look like 4150 cams with a larger shaft cutout. Going to be doing some testing with them on some gas Dominators to see how they work. I like the bypass jet as well, how big are you going to start with? Maybe .020-.025?


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 Post Posted: Tue Aug 16, 2011 7:59 pm 
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I am starting out at .020 and see what it does.

I tried messing with those white cams, for my engine,it didn't have enough pump shot up front, So coming off of idle, it would hesitate. My engine seems to like a quick initial shot, with low volume.

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 Post Posted: Tue Aug 16, 2011 8:12 pm 
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Great Idea!!!!!!!
I did mess with my pump cams and did get them to work out real well,, =;

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 Post Posted: Tue Aug 16, 2011 8:19 pm 
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I can't take credit for the idea, got it from looking at the braswell float bowls, just figured out how to implement it.

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 Post Posted: Tue Aug 16, 2011 10:07 pm 
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Great idea! It looks like it would benefit the street driven cars by letting the accelerator shot bleed off when moving the throttle slowly, since the extra gas is not needed, instead of wasting the gas through the engine. I think it would help in the gas mileage department quite a bit.

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 Post Posted: Tue Aug 16, 2011 10:19 pm 
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Slowpoke wrote:
Great idea! It looks like it would benefit the street driven cars by letting the accelerator shot bleed off when moving the throttle slowly, since the extra gas is not needed, instead of wasting the gas through the engine. I think it would help in the gas mileage department quite a bit.


Ya know, I was thinking that same thing when I first read what he had done. Easing the throttle open eliminates the need for a pump shot anyway and like you said, this deal will allow that pump shop to ease back into the fuel bowl instead of discharging out of the squirters.

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 Post Posted: Thu Aug 18, 2011 10:18 am 
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It also eliminates issues with vibration causing a rich condition from working the pumps.

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 Post Posted: Thu Aug 18, 2011 11:00 am 
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Good point, I didn't even think about that.

Seems there may be many realized benefits to this.

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