Let us know what you end up doing; never heard anyone really solve this short of a fuel cell. Although it's a well-known problem, it seems some cars are just more prone to it than others. The only time I've had fuel starvation, the car was truly running on empty -- I came off the track immediately but ran out of gas within 3 miles trying to get to a station. Autoxers seem to get it worse, perhaps because the many short, hard transitions causes more sloshing than on a road course? Anyway, good luck.

 

Well if one were to put foam into the tank, what's the best way to do it? (Please don't say filler neck!)

 

I think this is a very important point, and worth exploring. If it is true that some cars are more prone to the problem than others, that would indicate that you could FIX your problem with OEM parts.

I, for one, have only experienced this problem when I ran on one 'bar' of fuel during an autocross, just to test the limits. On the other hand, I've done many autocrosses with varying grip levels. I've spent time on a skidpad with R-compounds doing sustained lefts and sustained rights with 1/4 tank. So, I personally think that I may have one of the cars that is 'immune' to this problem.

If this theory is correct, that some cars are immune and some are prone, could it be explained by the fuel pump (some are in better condition than others)?

Can anyone shed light on whether or not this theory is accurate. Someone who's owned a couple of S2000's, or been to an event where one car had MORE fuel but experienced starvation while another car with similar preparation and less fuel did not?

 

I wonder if my fuel pickup line is pointing left--which would cause the problem in a left turn with the fuel sloshing to the right. I am going to get in there and look. but the helms manual seems to indicate it should point straight down, so i dont know.

 

This is a very common auto-x issue. Really good tires will make the problem much worse. I was getting fuel starve with anything less than 3/4 tank. I'm now testing a prototype fuel pressure accumulator which is working perfectly. I have run with the same conditions with only 1 fuel bar showing and have never experienced any fuel starve since the install. You can also run dual fuel pumps.

Regarding foam, it typically comes in cube shaped blocks and could be installed through the fuel pump opening. I haven't tried it but some motorcycle racers told me that it will help with preventing the rapid slosh but won't help with a sustained side load leading to fuel migration away from the pick-up. Therefore, I'm skeptical but please try it and tell us the results.

 

Good point about the pickup locations. Perhaps this is something that is not tightly controlled during manufacturing...

 

The only time I have ever had fuel starvation was when I was nearly empty. I limped off the track, and didn't even try to get to a gas station, filling up instead with the expensive race gas at the track. Otherwise, I've been pretty empty on the track with no problems many times; I just make sure not to go more than about 90 miles without filling up (the fuel gauge is completely inaccurate when using gas as fast as I do on the track, so I pay no attention to it, only to the accumulated miles since last fillup).

I tend to keep it at least 1/3 full at autocross, and I've never had fuel starvation problems there.

Could this be an AP1 problem, largely fixed for AP2's?

 

AP2's are just as bad

 

has anyone actually fixed this--short of replacing the tank

 

I was at Nelson Ledges with my AP2 (2006). Started getting starvation in the last 2 or 3 turns of my last lap and pulled it in. Fuel gauge said I had 1/3 of a tank left, so I figure I could make it to a gas station. Idled for 2 mins, and ran out of gas.

Nelson's is run clockwise, so most turns were right handers...so take that for what it's worth.