It's not F1 but there are still substantial differences in weight depending on how much fuel you have. For ITR guys, what MPG do you usually get at the track and how much fuel do you keep in the tank before you go out in your run group? I dont want to keep much more in the tank than necessary.

BTW I know what happens when you run out of gas on track, so no need to educate me.

 

i always fill up at the beginning of the day and fill up a gas can then too. i then use the gas can before the last session.

i started to do this after a session at roebling where i had a little left than a 1/8 of a tank in a session and i sucked air during a turn (turn 2) and the car actually shut off.

really for a HPDE i'd rather the peace of mind of having a full tank over the competetive advantages of saving weight with like 3/4 of a tank.

 

not "competitive advantages"...it's an HPDE, not racing.

But running light on fuel will make a difference. Just like removing your spare, or rear seat. Maybe not much but you might be able to brake a little earlier here and there, or get a mph or two more coming out of corners.

 

I have always filled up the tank before each day. and usually burn through almost all of it in ~1.5-2.0 hours of track time. I'd average 9-10mpg. As stated above I rather have peace of mind then missing a session or worry about stalling in the corners during the last run of the day.

 

At VIR in February, I was burning a healthy 1/3 of a tank per 30 minute session. Translation: bring gas. a LOT.

 

So a 1/2 tank is probably safe.

 

What makes more of a performance advantage is making sure the fuel isn't able to slosh around. This means either fill it up or keep it empty. A half tank of fuel sloshing around can throw substantial amounts of weight around.

I bet you can shave more time off by working on your driving than you will by running a lighter fuel load . . .

 

Fill it up, sometimes twice in one day

You wont see a difference, I dont think.

Bryan

 

Full Tank.

 

FULL tank. I get between 11-12 MPG.

 

full tank, yes it is not competition.


[Modified by ITACivic, 1:40 PM 4/12/2002]

 

Full tanka t the begining of the day


And Ross just got owned by Drew...

 

Full tank!
I went to measly Jefferson Circuit on half-a-tank and was getting fuel starvation on tank slappers by the second session.

 

Full tank.

At VIR, my car is starved for gas coming out of Turn 1 and 2 by the third session on EACH day.

 

read my original post...I know what happens.

Drew, interesting point about not letting the fuel slosh around. And I obviously understand the bit about the driving...but I have had experiences where having a light fuel load changed the behavior of the car in a straight-line sense. To me it falls into the category of weight reduction.

 

While we are on this "silly" question, I dont want to start a new one for my just as silly question.

I have a HPDE this Sun at Sebring and I have 1k miles on my latest oil and filter (M1 syn w/bosch filter). Yay or neigh on the change?

 

I was thinking of keeping it at a certain level...as in, determining how little I can put in, and topping off to that level after every session. But what Drew said about it sloshing around makes a lot of sense as well.

It's not a matter of "owning"...I have detected a certain sentiment among the VA HPDE crowd that some of them would rather not share the track with me. Everyone is entitled to their opinion but this thread doesn't need to go there.

on second thought, let's lock this now. I've got the information I needed.


[Modified by Ross, 5:05 PM 4/12/2002]

 

I'll share the track with you! I think I hold the world record for offs...

 

Full tank here.

My car coughs around 1/8 tank left on hard left handers. If you cough going up the esses @ VIR or down the chute @ SP, well... I hope you have some spare traction.

Warren

 

in one HPDE, maybe so...lol

 

Full tank!
with 4 sessions, you will easily get past below half, and not too far below half im turning hard enough that i hear engine sputter in the long sweeper of turn 2 at thunderhill. Theres no reason not to fill up, besides, what does competitive advantage have to do with HPDE events? you dont want to be the ******* limping back to the pits holding up traffic in the middle of a session, or having to have the tow truck pulled out. they are not merficul when towing, especially if you dont have external tow hooks.

 

Nothing, if you read my post. I dont care about being faster than the next guy in a similar car...However I would like to be as fast as I can be, faster than I was the previous session, etc.

If there is any question that extra weight affects you...I can think of many places on my "home tracks" that could be done a bit quicker with less weight, places where straight-line acceleration from a low speed is demanded. Oaktree comes to mind. Less weight powering out equals more mph on the straight...and isn't going quicker what this whole thing is about?

 

It's only a few pounds, just **** before you run and have a full tank...nothing more annoying than having to cut a session short cuz of low fuel. To the brim!!!

 

Well you can either change it before and have to drive with the oil that was in your engine during the HPDE until your next oil change, or you can change it after so you don't have to do that, but then you're forced to run your car hard with the old oil. If you want to be ****, just change it before and after. I think the common practice is to just change it before.

 

eh, i got a minimum weight requirement anyway to worry about. better to take off from the top than the bottom. gas tanks are right where you want your weight to concentrate, in the rear and down low. youre right, better to come out of the turn 1-2 mph greater, but "competitively speaking" youre removing weight from where you need it, so youre going against yourself on that. go ahead and start off with a half tank if you think that makes you more competitive (it probably wont matter anyway), just bring extra 5 gallon tanks of fuel, cuz you wont last the day. as was said, concentrate on driving faster than saving 10 lbs of fuel. I know for me I cant race well when I'm thinking about the not having enough fuel to make it to the end of the session and looking at the guage and not the track.