Thread: Endurance racing (maximize fuel use)....

I help a local group of racers occasionally wrench on an SE-R that they run in the Chump series. Last year they did a couple races, and they are looking at running another 5-6 this year. They have had several issues that are/have gotten worked out, but fuel usage is one that I've never encountered.

They typically run 2 hour shifts while driving. The issue is that they have to stop to fuel about 1 hr 40 minutes into each session (obviously not getting a full 2 hour shift). While this may not sound like a large issue, it adds time if you are running an endurance race of any real length (they have an extra pit stop where the other racers can continue to run).

While doing a little testing, we were able to run the fuel tank "dry" while pumping fuel into cans. When the pump was basically only pulling air, there was still ~1" of fuel in the tank (we didn't drain the tank to measure it exactly). So the question has anyone run into an issue like this. Can you lengthen the fuel pump pick-up or something similar to get the last drops? Or has anyone figured out a safe way to add a little extra capacity?

They would prefer to stay with the stock tank for now instead of moving to a cell. Also, they can get assessed penalties for fancy upgrades since this is Chump Car.

Looking for tips.

Josh

How bout making it a rear sump? That would give ou a little extra gas, and you shoul dbe able to run it lower with fuel. Hope it works out!

the constraint I see is that even if you lower the pickup that one inch of gas is not stationary in the corners its pressed against the side of the fuel tank.
I would work on the tune if possible to minimize consumption , and look into increasing the diameter of the filler neck to hold a little extra fuel when you top it off.

We were concerned that fuel was getting all of the way up the neck. We started pumping it out before checking to see where it was. Good idea. Maybe a redundant line in the trunk?

Josh

in theory you are looking for a 17% increase in capacity if all else stays the same so over 2 gallons
tech may be an issue with an extra fuel line in there
the entirety of the line would need to stay below wherever the fuel level gets to. and you would want to add a vent so that it actually fills. tie into the gas tank vent?
I'm not sold on that idea.

maybe use a bigger sock on the fuel pump? or an extension from the pump to sock?

have you had issues with losing fuel all over the side of the car when the tank is full? that is an issue that needs to be addressed on my brothers car, and he always tops it off because he is close to being under weight. adding weight and not topping it off will fix that though.