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Discussion Starter #21
Yes, mostly. If you have 58PSI at all times because you have a garden hose for a supply and return line, and you tune for AFR, your adjusted VE table will reflect it. Similarly, if you have 58PSI through a crazy straw that drops to 45PSI as your demand increases through a pull, and you tune for AFR, your VE table will reflect it.

So while fuel pressure is not specifically accounted for with a sensor in OEM configuration, fuel pressure definitely has an impact on your VE tables. When it gets dangerous is when you tune on a dyno in the 1:1 gear, but then you go pull in the 1:1 gear where a pull takes a different amount of time due to external conditions. Fuel pressure doesn't drop exclusively with engine RPM, it drops with time when pressure drop through the line is a factor.

Good luck on your project!

thx, I'll see how it goes. I plan on doing a detailed writeup on ho to do the bucket mod. Too much stuff left out of older threads and some pics dont show up.
 

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I read this before leaving work this morning and thought about it the whole way to work. This actually isnt a bad idea. I could mount a stock fuel pump and sock near the rear wall and feed the bucket with it. I'll try the 8.1 bucket first. see how that goes.
The fpr bypass doesn't feed the bucket, it creates low pressure which draws fuel from outside the bucket, in.

The secondary pump does the same thing. I think a lot of guys have it set up so both pumps get fuel from inside the bucket. The main pump feeds the engine, the second pump feeds the venturi. The low pressure created by jet in the venturi draws fuel from the tank in, filling the bucket.

Search on this site, there is a thread of a member that showed a video of a stock pump hooked up to the port that shoots into the venturi. The pump qas getting its fuel from inside the bucket. He had it in a larger bucket barely filled with fluid. Initially the fuel bucket fluid level was the same as the big bucket level. Power on, inseconds the bucket was overflowing and a fountain was spewing fluid out of the top of the bucket.

I'll find it later and post it. You can do the same with a stock bucket, but the effect seems better with the 8.1 bucket.
 

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Discussion Starter #24

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shoot, do both the baffles and the twin pump with the venturi booster. throw some cool trap doors in there too like they have on the neato baffled oil pans. :hbang:
 

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Discussion Starter #26
shoot, do both the baffles and the twin pump with the venturi booster. throw some cool trap doors in there too like they have on the neato baffled oil pans. :hbang:
I’ve been thinking about what I’m gonna do. If I can find a fuel tank cheap enough I may get it and do some baffling to it. I could build a chamber around the fuel pump area and that would trap fuel and keep it from sloshing. It would kind of act like a bigger bucket. I’m all about overdoing stuff but I feel like it needs to be a reliable way. Adding another fuel pump to feed the bucket seemed like a decent idea but then there’s more wires that need to be run. More complexity. More points of failure. And a unknown failure of the feed pump could be disastrous if I’m not paying attention to the afr gauge. I could build in some fail safes but then there’s more wires and complexity again. I’ll attack it with the planned plan first. And add on as I go. Pulling the tank only takes a few minutes anyways so I can revisit it whenever.
 

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I’ve been thinking about what I’m gonna do. If I can find a fuel tank cheap enough I may get it and do some baffling to it. I could build a chamber around the fuel pump area and that would trap fuel and keep it from sloshing. It would kind of act like a bigger bucket. I’m all about overdoing stuff but I feel like it needs to be a reliable way. Adding another fuel pump to feed the bucket seemed like a decent idea but then there’s more wires that need to be run. More complexity. More points of failure. And a unknown failure of the feed pump could be disastrous if I’m not paying attention to the afr gauge. I could build in some fail safes but then there’s more wires and complexity again. I’ll attack it with the planned plan first. And add on as I go. Pulling the tank only takes a few minutes anyways so I can revisit it whenever.
what fuel pump do you have now?

if it's not the max size you can go with a drop in, simply getting a higher capacity pump might help you somewhat, so there is more fuel that will be bypassed by the FPR.
 

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Discussion Starter #29
what fuel pump do you have now?

if it's not the max size you can go with a drop in, simply getting a higher capacity pump might help you somewhat, so there is more fuel that will be bypassed by the FPR.
I have an aeromotive 340
 

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Discussion Starter #30
Ive been thinking about making a high volume bucket. I could use aluminum, weld a bottom on, weld in the tubing for the venturi/regulator and make provisions for the spring loaded rods and flapper valves. the more I think about it, the more i'm thinking its doable. I could easily make room for two pumps and have the second one boost activated. hmmmmmm
 

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Go return style with twin pumps, one boost referenced and have the return feed into the bucket and call it a day. I did that with stock bucket and zero problems going on 6 years.
 

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Discussion Starter #32 (Edited)
Go return style with twin pumps, one boost referenced and have the return feed into the bucket and call it a day. I did that with stock bucket and zero problems going on 6 years.
I do t have problems under 7ish psi. When I turn the wick up to 12 or 13, and I don’t have over half a tank, it starves for fuel. I’ll put it to you this way. My injectors with support around 800hp (flywheel) at my duty cycle. I’m not saying I have 800hp, but injector calculators point to that area. It’s probably around 700 flywheel. It’s hard for me to say that because I don’t like to inflate or exaggerate. But I’ll be honest. As hard as it pulls, the boost I’m running and mods I have all lead me to believe it’s putting over 600 at the tire. I’ll find out when I sort the fuel system out. Hp numbers don’t mean anything to me tho, 1/4 mile times and mph is what I care about. Mph more than anything.
 

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Discussion Starter #33
Well my guys, my aftermarket fuel pump assembly came in today. I don’t like how it’s designed. I’m gonna send it back and I guess find a factory one used. What I should have done first. Just pushes my project further back. I may just say screw it and use my original assembly. I’m getting impatient and that usually doesn’t work out good for me lol.
 

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Discussion Starter #34
Ok fellow poopoo heads. I had a wild hair. Got home from work and said eff it. Pulled the tank out and built the 8.1 fuel pump with my stock one. Yolo. Lol. I was gonna do a write up but there’s a few on here and I did it different anyways. I’m flocking picky so I used factory style stainless crush clamps on the connections. Flex hose. I mounted the static grounds. Soldered the fuel level wires directly to the level sensor. It took me way too long and I started to take pics but lost interest because I was trying to get it together tonight to go do some roll racing.

Anyways. I only had a couple gallons in the tank when I put it back together. Needle was in the read. Low fuel warning was on. I put it on 4psi. Made a hit. Afr good. Keep in mind, I’d never even get into boost at this low fuel level. It would certainly lean out. So I got brave. Turned it up to 7psi. Made a hit. Afr still good. I put 5 gallons in the tank. 80 mile range. 1 tick below half tank. Turned it up to 12 psi. Afr good. Absolutely half tank, 100, miles or below, we having issues. So I’ve made headway. I’ll have to run it down a little to see what my limit is.
 

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Discussion Starter #35 (Edited)
Something else. I pulled the fuel pump out and the level in the bucket was very shallow. I had just cranked the car a few minutes before. So in my mind the fuel bucket should be full. You can see in this pic how much fuel it has.




My clamp kit



Pump









 
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