LS1GTO Forums banner
1 - 20 of 25 Posts

·
Registered
Joined
·
365 Posts
Discussion Starter · #1 · (Edited)
I'm looking to completely redo my fuel system with new pumps and go with a boost referenced regulator and return style setup instead of the Proxses DW400 kit that I've been running the last couple years. I see a couple places out there like Hinson advertise a dual pump setup but it completely does away with the bucket. I've been known to drive my GTO low on fuel now and again and I feel like completely deleting the bucket would introduce issues with fuel slosh around corners. Does anyone on here have input on how they've done their setups? I saw @Kfxguy fabbed a custom bucket which looked sweet but sadly I don't have a TIG welder at my disposal.
 

·
Premium Member
Joined
·
2,108 Posts
Have pictures of the proxses? I cut the bottom of the bucket off personally. All my testing showed the venturi wouldnt keep up with a single pump at higher power. Which would be a hindrance on a standard pull cause the bucket wouldnt refill fast enough.


Anyways ive been down to 1/8 tank no issues for basic driving
 

·
Registered
Joined
·
2,982 Posts
Because the tank sits sideways, you will have serious issues with fuel slosh below 1/2 a tank if you get rid of the bucket. thats why I fabbed a bucket to hold over 2 liters of fuel. My advice is if you need dual pumps then cut all the junk out of a hummer bucket and make that one work...its a common mod here and i forgot what they called that bucket. I'd run a stock pump for your main fuel (i'll explain in a minute) and then run like a 525 pump being activated at 1-2psi. Then run another stock or low volume pump from the back side of the tank baffle to the bucket. Activate this one too under boost. That will keep the bucket full under full power.
Why the stock pump for main pump? I have two aeromotive 340's and just cruising around with one pump running, its bypassing so much fuel that in a hour or so of driving it will over heat the fuel and cause a pressure drop.

I have not done this, but That was what I was going to do if I could not be successful with a custom bucket. Next time I'm in there, I think i'm gonna pull the 340's out and do a 525 and a stock pump. i re-aimed the return fuel to hit the sidewall of the bucket and that seemed to help. It was all the way at the bottom constantly returning heated fuel right to the pickup....The problem was much worse when it was like this. I lowered the fuel pressure a little and that helped too....it takes way longer for it to happen now. I think if i put a stock pump in for cruising, it will fix it. learn from my mistakes. lol
 

·
Premium Member
Joined
·
2,108 Posts
I have no issues with a 340 only and return system on longer drives. I left the bucket walls and havent seen any slosh problems either but im not driving around town like im on a roadcourse. Heated fuel isnt causing a pressure drop unless your regulator isnt working properly.. its whole purpose is to maintain a set pressure the temp of the fuel doesnt make a difference to the regulator.

Less parts the better. If you need more than 1 pump then id do duals on a hobbs. Still think the bucket is worthless. The only way to keep a bucket full is have as much pumping into it as you do out.
 

·
Registered
Joined
·
365 Posts
Discussion Starter · #5 ·
Have pictures of the proxses? I cut the bottom of the bucket off personally. All my testing showed the venturi wouldnt keep up with a single pump at higher power. Which would be a hindrance on a standard pull cause the bucket wouldnt refill fast enough.


Anyways ive been down to 1/8 tank no issues for basic driving
It's been a while since I messed with the setup but here's a pic of when I first got the setup. The upper part of the bucket gets replaced with the pump assembly on the left and there's a standalone regulator that sits in the tank seen on the right.
510371


Because the tank sits sideways, you will have serious issues with fuel slosh below 1/2 a tank if you get rid of the bucket. thats why I fabbed a bucket to hold over 2 liters of fuel. My advice is if you need dual pumps then cut all the junk out of a hummer bucket and make that one work...its a common mod here and i forgot what they called that bucket. I'd run a stock pump for your main fuel (i'll explain in a minute) and then run like a 525 pump being activated at 1-2psi. Then run another stock or low volume pump from the back side of the tank baffle to the bucket. Activate this one too under boost. That will keep the bucket full under full power.
Why the stock pump for main pump? I have two aeromotive 340's and just cruising around with one pump running, its bypassing so much fuel that in a hour or so of driving it will over heat the fuel and cause a pressure drop.

I have not done this, but That was what I was going to do if I could not be successful with a custom bucket. Next time I'm in there, I think i'm gonna pull the 340's out and do a 525 and a stock pump. i re-aimed the return fuel to hit the sidewall of the bucket and that seemed to help. It was all the way at the bottom constantly returning heated fuel right to the pickup....The problem was much worse when it was like this. I lowered the fuel pressure a little and that helped too....it takes way longer for it to happen now. I think if i put a stock pump in for cruising, it will fix it. learn from my mistakes. lol
I'm surprised you have fuel boiling issues when only running one 340 pump. Do you think that's an issue with a return system? I was thinking of going to the 8.1 bucket assuming that's what you're referring to, and modifying that for the pumps. I was thinking of just running 2 Walbro 450s as that seems like what most people run online though.

I've definitely had issues with fuel cutout around corners in this car with the venturi not functioning correctly so I'm thinking keeping the bucket might be a good idea.
 

·
Registered
Joined
·
100 Posts
I know you were following my ZR1 pump module install, which has an excellent ability to feed itself to the very bottom. I didn't get it to work the way I wanted to hold a constant 58 psi at the rail, but I switched over to manifold reference mode with the PWM controller, and it does a fairly good job of holding a constant Effective Pressures. I did need to add a larger pressure line from the tank to the front to get where I wanted to be.
I'll be following to see what you end up doing here for the sake of using the whole tank.
 

·
Registered
Joined
·
365 Posts
Discussion Starter · #7 ·
Thanks JTRR. Also I haven't heard much about the Lonnie's performance dual pump setup recently. Does anyone still use that anymore? He retains the factory bucket so I'd think fuel slosh is probably good.
 

·
Premium Member
Joined
·
2,108 Posts
Thanks JTRR. Also I haven't heard much about the Lonnie's performance dual pump setup recently. Does anyone still use that anymore? He retains the factory bucket so I'd think fuel slosh is probably good.
Good luck. The stock bucket doesnt let enough fuel in fast enough for a 700hp boosted application (which is what a stealth 340 is rated to). Even a standalone stock pump couldnt feed it fast enough through the venturi. Itd absolutely be fine for dailying but once yoy expect that 340lph to feed the 700hp the bucket goes empty in 5s from my testing
 

·
Registered
Joined
·
936 Posts
Just drop in any pump and put a hydra mat on it and call it a day.
Only had issues with my pumps using standard stocks at 1/8 of a tank on hard turns. But I tend not to go that low with a car on e85 and the no flex sensor.
 

·
Registered
Joined
·
365 Posts
Discussion Starter · #10 · (Edited)
Just drop in any pump and put a hydra mat on it and call it a day.
Only had issues with my pumps using standard stocks at 1/8 of a tank on hard turns. But I tend not to go that low with a car on e85 and the no flex sensor.
Mind posting up some pics of your setup then? I’ve heard Hydramats are sweet but I’m pretty particular about fuel cutting out and pulling the tanks out of these cars are a pain so I’d only like to do it once when I decide how to do my system.
 

·
Registered
Joined
·
100 Posts
Just drop in any pump and put a hydra mat on it and call it a day.
Only had issues with my pumps using standard stocks at 1/8 of a tank on hard turns. But I tend not to go that low with a car on e85 and the no flex sensor.
I like the idea of the hydra mat, but I've never seen any details about what size people are using and how they are installed and spaced of the bottom, etc. Any photos out there?
 

·
Premium Member
Joined
·
2,108 Posts
Lol I don't know what universe you live in that you can pull a GTO tank quickly. Maybe I'm just spoiled because dropping the tank in my G-body is 2 bolts and 2 minutes.
4 bolts for the tank brace, two nuts for the straps inside the trunk, two under the car and the plastic cover, 3 at the fill nozzle if you really want to pull it all the way out. Disconnect two lines. Ill let you have half hour ;)
 

·
Registered
Joined
·
365 Posts
Discussion Starter · #15 ·
4 bolts for the tank brace, two nuts for the straps inside the trunk, two under the car and the plastic cover, 3 at the fill nozzle if you really want to pull it all the way out. Disconnect two lines. Ill let you have half hour ;)
I’ll give you that one. As far as the pump setup goes though, do you have any pics of your current setup?
 

·
Premium Member
Joined
·
2,108 Posts
No i didnt take any. Cut the bottom out of the bucket, ziptied a stealth 340 in and run it. Return through the top hat. Nothing special. I tried a few bench setups with the venturi. Itd work under "normal" driving but anything "full throttle" and it couldnt keep up. The little flap valve didnt seem to let fuel in fast enough either.



Heres two oem pumps in the bucket. One feeding the regulator and another straight feeding the venturi. Still wouldnt keep up and we all know the stock pump wont support much anyways.

 

·
Registered
Joined
·
365 Posts
Discussion Starter · #17 ·
No i didnt take any. Cut the bottom out of the bucket, ziptied a stealth 340 in and run it. Return through the top hat. Nothing special. I tried a few bench setups with the venturi. Itd work under "normal" driving but anything "full throttle" and it couldnt keep up. The little flap valve didnt seem to let fuel in fast enough either.



Heres two oem pumps in the bucket. One feeding the regulator and another straight feeding the venturi. Still wouldnt keep up and we all know the stock pump wont support much anyways.

I’d be curious if an 8.1 bucket would hold up any better. I read earlier today that the Venturi on that bucket can be drilled out for a higher capacity.
 

·
Premium Member
Joined
·
2,108 Posts
I’d be curious if an 8.1 bucket would hold up any better. I read earlier today that the Venturi on that bucket can be drilled out for a higher capacity.
Idk i got tired of testing then almost caught the house on fire. If youre really serious a surge tank is the way to go anyways.

On the factory bucket the only drilling possible was from the top down into the venturi fitting which really wouldnt change much since the jet size would be the same. The venturi should work better with the smaller jet theoretically anyways. Smaller jet = increased velocity = greater pressure drop. Pressure drop is what the venturi works on
 

·
Registered
Joined
·
2,982 Posts
It's been a while since I messed with the setup but here's a pic of when I first got the setup. The upper part of the bucket gets replaced with the pump assembly on the left and there's a standalone regulator that sits in the tank seen on the right.
View attachment 510371


I'm surprised you have fuel boiling issues when only running one 340 pump. Do you think that's an issue with a return system? I was thinking of going to the 8.1 bucket assuming that's what you're referring to, and modifying that for the pumps. I was thinking of just running 2 Walbro 450s as that seems like what most people run online though.

I've definitely had issues with fuel cutout around corners in this car with the venturi not functioning correctly so I'm thinking keeping the bucket might be a good idea.
I think it’s because my return is too small and I don’t feel like changing it anytime soon.
 

·
Registered
Joined
·
365 Posts
Discussion Starter · #20 ·
So after giving it some thought this morning I think I'm going to go with a different solution. I'm going to give it a try with a Holley Hydramat with a -10 outlet and a Y fitting to feed 2 pumps, probably Walbro 450s. The one I went with is a 30"x14" mat so assuming that covers the majority of the tank bottom I shouldn't really ever have issues with running out of fuel, even at low levels. This would let me hack up the bucket and delete the venturi altogether.
 
1 - 20 of 25 Posts
Top