Fuel consumption on the track?

mazmad · Postby **mazmad** » Tue May 21, 2013 10:40 am

Anyone have any idea what a 1.8 vvt engine will chew through on the track? My fuel gauge is way out, and short of filling the tank, having a session, and then siphoning it down again, I have no way of calculating it.

Thanks!

manga_blue · Postby **manga_blue** » Tue May 21, 2013 11:13 am

I tend to budget by laps. SMP South is the lightest at around 0.6 litres per lap. Philip Island is heaviest at 1.5.

mazmad · Postby **mazmad** » Tue May 21, 2013 11:20 am

Thanks Phil. Obviously varies from car to car, but that's a starting point - what kind of power are you putting out?

zero00 · Postby **zero00** » Tue May 21, 2013 12:25 pm

Filled my NB8A last night coming home from Queensland Raceway - 387km and 39.3L, calculates at 10.15L/100km

Consisted of 279 'road' kilometres travelling thru the back streets of Brisbane then 108km on the track doing NINE runs with tacho around 5000-7000 all day

Not bad .. should have gone with a lighter fuel load and taken 2 x 10 litre containers!

manga_blue · Postby **manga_blue** » Tue May 21, 2013 1:21 pm

mazmad wrote:Thanks Phil. Obviously varies from car to car, but that's a starting point - what kind of power are you putting out?

I'm guessing 80-85 rear wheel pussywatts. What I do is start the day at about 1/8 full, do a session or two and then top it up to the same mark. Then calc the litres per lap. Consumption varies with temp and grip too.

mazmad · Postby **mazmad** » Tue May 21, 2013 1:30 pm

Yeah cool thanks guys. My gauge fluctuates, starts off at one level and then drops by at least an 1/8th when the car moves at all.

rascal · Postby **rascal** » Tue May 21, 2013 1:47 pm

my 88kw NB8A gets 190km out of a (std) tank at Phillip Island, (40 odd laps)
Slower/tighter tracks like winton its closer to 250 as full throttle % is lower...

mazmad · Postby **mazmad** » Tue May 21, 2013 2:03 pm

Interesting rascal - mine is nb8b prob about same kw. So that's a tad under 5km per litre, which is about what I would have expected.

OurCognitiveSurplus · Postby **OurCognitiveSurplus** » Tue May 21, 2013 2:13 pm

I worked it out to be about 40L/100km in a stock NB8A.

lee · Postby **lee** » Tue May 21, 2013 4:10 pm

Those are some surprisingly low fuel consumption figures, considering those with V8 Commodores often get fairly close to that with moderately spirited road driving!

rascal · Postby **rascal** » Tue May 21, 2013 4:22 pm

Road driving, even moderately spirited, is NOTHING LIKE driving on a racetrack.

mazmad · Postby **mazmad** » Tue May 21, 2013 4:32 pm

I hope not. Don't want to be on the road with someone else driving full tilt like that!

You won't get much change from 5.5k rpm on the track, unlike on the road.

manga_blue · Postby **manga_blue** » Tue May 21, 2013 5:15 pm

Engine tune plays a big part too. It's more of an issue for NAs which were set so stupidly rich at WOT. Reflashed or aftermarket ECUs can reduce NA track fuel consumption by 30-40% compared to standard OEM ECUs. My ECU mods paid for themselves in the first year.