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PostPosted: April 13, 2011, 11:04 am 
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Location: Denver,CO
I'm starting some work on my fuel system and I am having issues deciding what to do with my fuel tank and if I need a surge tank.

Currently I have an rci 12 gallon tank. Image There are no baffles inside and it has a 1/2 tube that sits about .25 from the floor of the tank, near the center. I most likely will be drag racing this car and it may experience a little bit of track time but that will be minimal.

My though is if I leave it as is it will be ok for street driving and track as long as I keep it over 1/2 full. I have been considering a surge tank but that would add a considerable amount of money to the fuel system. I've also looked at snowmobile fuel pick ups (all the cool offroad guys use them).

Do you all think I'll be ok leaving it as is or should I look at a surge tank as well?

evo

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PostPosted: April 13, 2011, 1:00 pm 
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If it were my car I would start with just the tank and determine if a surge tank is required based on what the car is used for. If you find it is needed, it does not seem like a difficult item to add later.

You could even go as far as adding the wiring now just incase.

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PostPosted: April 13, 2011, 2:19 pm 
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First thing, I'd position the end of the fuel pick up tube to the rear of the tank. g forces will push the fuel to the back.

Also if you have room, maybe tilt the tank slightly so the back side is lower than the front with the pickup at the rear.

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PostPosted: April 13, 2011, 2:24 pm 
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What about build a "t" that you could attach to the end of the the fuel pickup to let you suck from either front or back?

--JOsh


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PostPosted: April 13, 2011, 2:31 pm 
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CRTurboGuy wrote:
What about build a "t" that you could attach to the end of the the fuel pickup to let you suck from either front or back?

--JOsh

Air is a lot easier to suck through a hose than gas, so if a T-fitting is used, it'll suck air from the front of the tank every chance it gets. If it were me I'd add one straight off.

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PostPosted: April 14, 2011, 2:14 am 
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Thanks also what do you all think of this inline fuel pump http://www.summitracing.com/parts/SUM-G3138/. Its a summit high flow for efi. I'll be using this on a stock v6 engine.

Or should I go with this one from JEGS http://www.jegs.com/i/JEGS-Performance-Products/555/159000/10002/-1?parentProductId=1167179 . Its a 190gph unit.

evo

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PostPosted: April 14, 2011, 10:21 am 
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First, you need to calculate out how much fuel your engine will need, but in general, the ubiquitous (sp?) Walbro 255lph pump is what everyone uses.

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PostPosted: April 14, 2011, 3:23 pm 
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Thanks I sifted through the maxima.org site and found a pissing match over which pump to us. I'll go with the 190 lph as thats what I ran in my turbo 626 years ago and it had more than enough fuel. The max guys say the 255 bumps up the base fuel pressure too much and I would have to run an afpr to fix it.

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PostPosted: April 14, 2011, 5:20 pm 
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Hey evo626, just want to say it sounds like your getting closer to an actual car! Congrats! :cheers:

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PostPosted: April 14, 2011, 7:13 pm 
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May want to consider this setup:
viewtopic.php?f=27&t=11744

If you aren't worried about fuel slosh, you may do best to weld a bracket that holds the modue to the bolt on filler flange. Only thing that could be hard is getting the return to dump back in the bucket.

Cheers.

Cory

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PostPosted: April 15, 2011, 12:24 am 
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So your saying it might be best to weld a bracket of sorts to hold the fuel pump in place to the filler flange, then run submersible fuel line up and out of the cell (in my case punch a new hole).

In this link http://www.zzperformance.com/grand_prix/products1.php?id=573&catid=113 do this include the jet pump (venturi) and the bucket, or do I need to buy the stuff as well.

This seems like a very good idea for packaging and what not.


Thanks.

evo

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PostPosted: April 15, 2011, 1:43 am 
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I have drawn a picture of how this might work. Inside my cell is a tube for the fuel pump. I can use this to attach the pump to it and somehow get the bucket to sit under the tube. Then I only need to drill 2 holes in the cell, one for power and the other for the outlet and cap off on of the other ports. I take it I need the fuel pump housing from a GTP grand am to make this work?
Attachment:
CIMG2242.JPG

evo


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Last edited by evo626 on April 15, 2011, 1:52 am, edited 1 time in total.

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PostPosted: April 15, 2011, 1:45 am 
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Well what happens is when the fuel pump burns out on some cars (fairly common. An independent shop probably does 1-3/wk) the entire module gets replaced. So go ask at your local mechanic if you can have their dead fuel pump modules (they are worthless to the mechanic).

The complete module looks something like this:
Image

You the remove everything but the bucket, and venturi (aka jet) pump. And you have something like this
Image
Ignore the valve. It doesn't matter.

You then install your walbro (or stock replacement pump) by putting it into the black sleeve, sticking a filter sock on the bottom, and connecting the black hose to the venturi nipple on the fuel pump (heat the end of the hose before stuffing it on. Just remember heat+gas fumes=bad).

Ok, so now you have your own custom fuel module. Build a bracket to weld to the bottom of the bolt on filler plate (make it fairly sturdy. Fuel can hit it pretty hard when sloshing). Strap or bolt the module to this bracket. Your RCI should have a pick-up tube on the "Fuel out" nipple. Cut part of this tube off, flare a bump on the end, and stuff a hose over it and secure with a hose clamp. Only problem is the pick-up tube is larger than the fuel pump outlet on the walbro. I had to stretch the **** out of the hose to get it over but I think it will be fine.

The only other thing to worry about is the return has to dump into the bucket. The jet pump can't keep up if the main pump is taking what is in the bucket and dumping it into the cell. So either make a bracket to hold the bucket under the return nipple, or make some sort of tube to direct the returned fuel into the bucket.

The jet pump does work, I've tested it. It will pull fuel from less than 1/4" and keep the bucket overflowing with nice cool gas (and your pump/engine happy).

Hope this helps.
Cory

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PostPosted: April 15, 2011, 1:57 am 
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Maybe the attached doodle will help show clearer what I am suggesting. Picture, thousand words et al.

Cheers.
Cory


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PostPosted: April 20, 2011, 8:16 pm 
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Joined: April 16, 2011, 11:05 pm
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Location: Melbourne, Australia.
All sorts of options here.

You could fill the tank with foam blocks to stop the sloshing, as done in fuel cells, or you can baffle off a very small section of tank, maybe in one corner, which traps some fuel each time during braking.

Another idea is a very flexible pickup hose with a weight on the end that follows the fuel around.
That is how aerobatic aircraft can fly upside down.

I prefer to run a simple lift pump into a tall skinny surge tank, and draw fuel from that.
The surge tank could be located anywhere, including inside the main tank with both pumps.


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