Ideal surge tank design for DSM road racing

[TSiAWD666]

For wiring I just used a relay sourcing power directly from the battery but using the oem fuel pump power line as the trigger. Just like how you'd re-wire an in-tank pump.

 

[CrashGNX]

For wiring I just used a relay sourcing power directly from the battery but using the oem fuel pump power line as the trigger. Just like how you'd re-wire an in-tank pump.

Beat me to it, yep id do the same.

 

[Ludachris]

I had been planning on mounting the surge tank under the car in a spot that would be tough to access. After seeing redhotridur's install in previous posts I'm wondering if mounting it in the hatch and building a sheet metal enclosure wouldn't be a better solution. I could do it using screws for easy access. Would that be considered safe? And would it be considered a "firewall" to meet the NASA requirements?

Anyone have any feedback on this quote?

 

[arrowhead]

The usage of fuel cell foam in stock gas tanks has been done with no problems and it works fine, cut out a reservoir in the block itself where the pick up would be, so fuel will stay in that pocket.

A word of advise DO NOT use the foam if you are running ethanol, unless the foam is made specifically made to handle it.

So how do you get around that in a regular fuel cell?, you use WIFFLE BALLS and stuff the tank with them they act as baffles and avoid sloshing in the tank to a large degree.

Maybe this could be tried in the regular gas tanks and I am sure it would help,
the IT series in SCCA did not required a fuel cell years ago and this is what I used in the tanks instead of the foam.

arrowhead

 

[CrashGNX]

The usage of fuel cell foam in stock gas tanks has been done with no problems and it works fine, cut out a reservoir in the block itself where the pick up would be, so fuel will stay in that pocket.

A word of advise DO NOT use the foam if you are running ethanol, unless the foam is made specifically made to handle it.

So how do you get around that in a regular fuel cell?, you use WIFFLE BALLS and stuff the tank with them they act as baffles and avoid sloshing in the tank to a large degree.

Maybe this could be tried in the regular gas tanks and I am sure it would help,
the IT series in SCCA did not required a fuel cell years ago and this is what I used in the tanks instead of the foam.

arrowhead

I've heard horror stories about the foam breaking down clogging everything and I just dont want to deal with that, I got enough problems tuning as it is . Gives me a chance to break out the squirt gun welder and dabble in tank design .

 

[arrowhead]

If this was a real problem. fuel cells would not bring them. and have never seen a fuel cell w/o them. and most racing org. require that you run a fuel cell. so it becomes a point of maintenance.

I have seen foam become powder after sitting for years in a cell, but this is not the case here and if given proper maintenance they will last a long time.

But to each their own.

 

[TSiAWD666]

This weekend I had my car at Summit Point in WV on the Main Circuit. Datalogs I think show I'm hitting about 1.5g laterally but I haven't done data cleanup to see if that is just noise (looks to be sustained if I visually average the turning sections). I ran my car as low as requiring 14.3 gallons for a full refuel without a single hiccup so I'd say my the 034 surge tank setup I have is working extremely well.

 

[CrashGNX]

Thats impressive! yeah a surge tank is the better way to go for sure. I was going to go that route but I dont have the space or money to get one. Instead I cut open a spare tank, baffled it and went to an external walbro pump inside the tank and 2 walbro pickups that close when they hit air. This allows me to run with anything over about 4 gallons in the tank without any issue but I opted for one of my pickups having a small air bleed in it so if I ran both pickups dry and they both closed I wouldnt end up with a vacuum locked pickup system. This was a good idea in theory but I should have either had the bleed closest to the pump or not at all because my passenger side of the tank doesnt get much gas sloshed into it due to my baffles and the vent pulls small amounts of air in leaning out the mix if im under about 4 or 5 gallons. Its working fine for now, 1/2 tank is less weight than a slam full tank anyday. I'm using this as a learning experience and I am designing a custom steel fuel tank to completely eliminate this problem. I'll build it this winter and have it ready for full testing at the start of the season next year.

 

[Colt4G63 also]

You can see my surge tank poking out under the left rear bumper. I feed it through the side of the swirl pot with a cheap lift pump made for a Ford truck. With no pressure resisting it, it flows plenty of fuel to meet more than my needs, and it has no problem self priming when the main tank starts running on empty. The Walbro 255 HP inside the pot is always submerged in about 10 inches of fuel, and feeds the fuel rail. The returned fuel goes back to the swirl pot through the side, and the excess comes out the top of the swirl pot, where it goes back to the main tank, and drains next to the pickup strainer of the lift pump.

Ps. In theory, since it's a sealed swirl pot, if the lift pump fails, or can't keep up, a vacuum should be created in the swirl pot, and draw fuel in through the return, and the lift pump, assuming fuel levels are not extremely low.

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[CrashGNX]

That is the only location I could come up with to mount the aluminum tank I have laying around but it is 18 inches tall so I would have to cut a hole into the trunk area there and box it off from inside the car for safety specs. im not sure if it would fit there even with hacking everything up. Also someday I would like to go to E85 or something of the likes and cant have bare aluminum in the system so I would have to re-engineer or rebuild it again then . Figure I'll just save the time money and body parts by designing a tank that solves the problem in the first place.

Update:
Well. got to run a session on the road course saturday and sunday this weekend. my baffle design and walbro pump pickup idea turned out to be a pretty epic fail so far. The fuel pump is cavitating and starving for fuel causing the car to lean out pretty bad. I've already drawn up plans and got steel for a new tank that should solve the whole issue hopefully. I'll build it as I have time over the next month or so.