Gas tank swap options.... let's discuss this

Ludachris · 07-14-2008, 08:47 AM

I'm tired of running a full tank of gas at the track only to have to fill up after a couple of runs because of the bad baffling. If I get down to near half a tank I get the dreaded sloshing in left hand turns and the engine starts cutting out.

Sure, a fuel cell would be ideal but the cost is high for road racers due to the requirements of a bladder for NASA. I think we need to start looking into a tank swap that could work. Maybe we need to hit up some wrecking yards (or friends' cars) and start taking measurements. Anyone already started doing this? I have a buddy with an Integra that doesn't have this problem until he gets close to empty. Maybe that would be a good tank to start measuring.

tsiboosted · 07-14-2008, 09:01 AM

Chris - Have you looked into the surge tank options yet? You can keep the OEM tank and have an external "surge" tank that pumps fuel into the system when the tank sloshes around keeping the car from cutting out on those left hand turns. I hate our tanks too as I have to run close to a full tank of fuel when I race. This is not what I waqnt to do as it weighs the car down.

And there is always the "foam" you can put into the OEM tank in addition to the surge tank to help hinder the sloshing in the tank itself. Just a few quick ideas I have had in the past. Nothing Im sure that has not been suggested before. Just revisiting them is all for this thread.

Also, something like THIS you may even could get and just get a bladder to put in it. It is IMCA approved as well. All fuel cells are really is this peice and an internal bladder. Just something else is all.....

And I dont really think it is necessarily the OEM tanks, I believe it is the where the pickups are located in the tank that causes this issues. Maybe the pick ups in the Integra tank are just better located than ours are. But anything is worth trying if we can get around this fuel issue to me.

talonTSIDriver · 07-14-2008, 09:27 AM

Not sure about 1g's, but 2g's have an issue with less than half tank and long/hard right handers. at Road America around the caracal, i would starve fuel causing slow exit speeds coming out as I would have to allow the fuel pump to catch up. If I were in it for hard core competition, I would have to do something about it. But for now, just keep a full tank.

I think a surge tank would be the hot ticket, cheaper and easier than messing around with a new gas tank.

drivemusicnow · 07-14-2008, 09:40 AM

I have a fuel cell, but before I was looking at a surge tank option. I think this is the most viable option with the cost and efficiency in mind.

I would use a stock fuel pump to fill a surge tank of volume between 2 liter and 1 gallon. This surge tank would have 3 fittings on it. Input from the fuel tank, overfill to the fuel tank, and output from the fuel pump.

Put your high volume fuel pump in the surge tank and make it narrow and tall enough that turns don't effect it. I would mount it in the rear by the stock tank.

As far as other stock tanks, you'd just have to go to a junkyard and try to find one that has a similar mount design, and then do some research on whether it has decent baffling characteristics.

tsiboosted · 07-14-2008, 10:02 AM

Quote:

Originally Posted by talonTSIDriver

Not sure about 1g's, but 2g's have an issue with less than half tank and long/hard right handers. at Road America around the caracal, i would starve fuel causing slow exit speeds coming out as I would have to allow the fuel pump to catch up. If I were in it for hard core competition, I would have to do something about it. But for now, just keep a full tank.

I think a surge tank would be the hot ticket, cheaper and easier than messing around with a new gas tank.

I know what you mean Andy. I run a full tank now and I dont like to, due to weight. But it is really (financially) my only option at this point. Will be trying a surge tank next I'm sure though.

Quote:

Originally Posted by drivemusicnow

I have a fuel cell, but before I was looking at a surge tank option. I think this is the most viable option with the cost and efficiency in mind.

I would use a stock fuel pump to fill a surge tank of volume between 2 liter and 1 gallon. This surge tank would have 3 fittings on it. Input from the fuel tank, overfill to the fuel tank, and output from the fuel pump.

Put your high volume fuel pump in the surge tank and make it narrow and tall enough that turns don't effect it. I would mount it in the rear by the stock tank.

As far as other stock tanks, you'd just have to go to a junkyard and try to find one that has a similar mount design, and then do some research on whether it has decent baffling characteristics.

I agree with what you are saying Greg about the surge tank being ther most viable and cost effective way to battle this issue. Like you said, you would really only need a surge tank that held a gallon or so of fuel to accomplish this.

talonTSIDriver · 07-14-2008, 10:07 AM

Quote:

Originally Posted by drivemusicnow

I would use a stock fuel pump to fill a surge tank of volume between 2 liter and 1 gallon. This surge tank would have 3 fittings on it. Input from the fuel tank, overfill to the fuel tank, and output from the fuel pump.

what about the fuel return line? Also, why run the stock pump, walbro 255 pumps are cheap.

turbosax2 · 07-14-2008, 10:18 AM

The return line would be best to go back to the large tank so you don't keep dumping fuel that has been heated right back into the surge tank. By dumping it to the large tank it gets a chance to be mixed around with other cooler fuel before returning to the surge tank. I would think a stock pump would be plenty sufficient to keep such a small surge tank filled up.

talonTSIDriver · 07-14-2008, 10:44 AM

Quote:

Originally Posted by turbosax2

The return line would be best to go back to the large tank so you don't keep dumping fuel that has been heated right back into the surge tank. By dumping it to the large tank it gets a chance to be mixed around with other cooler fuel before returning to the surge tank. I would think a stock pump would be plenty sufficient to keep such a small surge tank filled up.

I am just thinking about those LONG pulls with a big turbo and stroker setup.

turbosax2 · 07-14-2008, 10:52 AM

The 255 wouldn't hurt.

Here is some info on surge tanks:
Surge Tank Location, Installation and Design [Archive] - RX7Club.com
Tech Page

drivemusicnow · 07-14-2008, 11:00 AM

The stock pump would work just fine because it's essentially operating at 0 pressure. because you just care about having the surge tank full at all times, you want a pump that can fill it at high volume low pressure. It will fill the surge tank faster than the walbro could possibly empty it.

Figure the worst case scenario is a flat out sweeper that will last for maybe 10 seconds. in 10 seconds, you use maybe .2 gallons of fuel. (say 100mph, divide that out and you get .2 miles, I guarantee you're using less than .2 gallons of fuel And that's assuming 1 mpg)

The other option is getting some aircraft pickup pumps. They are high volume-low pressure and relatively cheap. But these really wouldn't be necessary when we already have a stock fuel pump that puts out plenty of volume.

And yes, the return line gets fed back into the main gas tank.

talonTSIDriver · 07-14-2008, 11:08 AM

Quote:

Originally Posted by drivemusicnow

The stock pump would work just fine because it's essentially operating at 0 pressure. because you just care about having the surge tank full at all times, you want a pump that can fill it at high volume low pressure. It will fill the surge tank faster than the walbro could possibly empty it.

Figure the worst case scenario is a flat out sweeper that will last for maybe 10 seconds. in 10 seconds, you use maybe .2 gallons of fuel. (say 100mph, divide that out and you get .2 miles, I guarantee you're using less than .2 gallons of fuel And that's assuming 1 mpg)

makes sense. +1 for you!

Ludachris · 08-01-2008, 11:47 AM

So I had an interesting discussion with a 3si guy who used to have a DSM. Turns out he actually modified his fuel pump float so that it pointed to one side and extended it and it solved this issue. I think I may have to look into this a little more.... just wanted to let you guys know.

tsiboosted · 08-04-2008, 09:59 AM

Quote:

Originally Posted by Ludachris

So I had an interesting discussion with a 3si guy who used to have a DSM. Turns out he actually modified his fuel pump float so that it pointed to one side and extended it and it solved this issue. I think I may have to look into this a little more.... just wanted to let you guys know.

I would be very interested to see how he modified it this to work better than what we have now. Let us know Chris

Savage Talon · 09-18-2008, 03:59 PM

Has anyone seen the inside of a 1G tank? I just cut the hump off of my parts car tank to make room for my spare tire hump removal project. I guess I could take some pics of it if you are interested. I plan to do some work in there to eliminate this problem while the top is off.

Ludachris · 09-18-2008, 05:49 PM

Quote:

Originally Posted by Savage Talon

Has anyone seen the inside of a 1G tank? I just cut the hump off of my parts car tank to make room for my spare tire hump removal project. I guess I could take some pics of it if you are interested. I plan to do some work in there to eliminate this problem while the top is off.

Please do.

Defiant · 09-19-2008, 05:08 AM

There was a pretty good thread of someone making their 1G trunk floor flat, but I cannot find the damned thing. I don't recall how much he dicked with the gas tank.

VETTE_50_TH · 09-20-2008, 09:39 PM

Quote:

Originally Posted by Defiant

There was a pretty good thread of someone making their 1G trunk floor flat, but I cannot find the damned thing. I don't recall how much he dicked with the gas tank.

What would that do to resolve the fuel tank problem? Im not sure how that helps. Expand upon this please.

James

Savage Talon · 09-22-2008, 01:17 PM

Well the gas tank has a hump in it like the rear hatch area. So in order to remove the spare tire hump out of the car something needs to be done with the tank. I think most just beat it in with a hammer to gain the clearance needed. But that's not something I want to do, I want to address the problem while I have access to the inside of the tank. I'm thinking of just putting a pump inside on the right side of the tank and having it pump fuel over into the baffle that the main pump sucks it's fuel from.