We had a endurance race few days ago with one Alfa 145, and there will be another endurance after 2 or 3 months and i'm planing to race with my 20VT......
It's 3 hours race and refueling can mix things on the track. We can refuel, but additional fuel tank can be mounted as well.
So my question is how much fuel 20VT can burn in single hour, 100km or whatever observation you may have can help.
I understand that ltr's per hour or km can vary depending or different tracks, but i really have no idea how much it can "eat" on the track.
Thanks....

In MPG terms (sorry, don't know l/km) you will be looking at approx 5 - 9mpg

When I was running 'only' 300bhp, I did a trackday at Bedford Autodrome.

I got 7.9mpg

If I did it again now, I reckon I'd be below 6mpg

Basically, I emptied a tank from full in just under 100 miles, which equated to about 80 minutes of actual driving

I did 200 miles at Donny earlier this year, when I sort of measured my fuel consumption, and I used 2 tanks of fuel in doing so. So definitely single digit mpg, probably between 6-7.

But what concerns me more about your plan is a 3 hour endurance race? You'll have massive cooling issues, brake temps, oil temps etc??! About 30 minutes is the max run I usually have before everything needs cooling down, and I do LOTS of track days. I'd be interested to know how you could adapt the car to run for this prolonged period?

for endurance racing i know in the lemans they run a 90ltr tank and bigger pipe lines and filters etc to get the extra laps.
as for the coupe i think its a 70 if my memory serves me right so running a bigger tank or a second tank would have its benefits

Hope cooling wont be a problem, on the last endurance here few days ago temps was 6-7 degrees and i think with reasonable race pace things may happen. The track is only 1.9 km long, 9 turns, and we were beaten only from one BMW M3 345bhp with one lap. And that's great result from Alfa 145 1.9JTD 105bhp with stock turbo, only remaped.
BMW spends almost 15 mins in the pits for refueling.
That's why i'm asking.

The Coupe tank is 63 litres

With hard driving on track i have minced a full tank and only got 90 miles.
So around 35 laps

Wow......extra fuel tank must be considered......

Stay out of first and 2nd lol seems to be when my coupe eats the most

I went round so slowly due to my 108db exhaust i got 500 miles to the tank

I was thinking about putting a 30 or 40 litre tank in my track car. I still think it's about right. Due to giving the coupe a rest/cooldown etc. What do you guys think ?

To replace your original one?????
It's only space saving, not weight - unless you need a very long running stints, it seems useless for me to replace your stock tank.

Yes for me its just open track days,so i can refuel when i want.
I hope to put a tank in the rear,and remove the original tank.

er - why not just put 30-40 litres in the standard tank? - the end result is exactly the same and it'll save you a fortune

Tanks for that Nigel !

Actually - my comment isn't strictly true...

On a modded Coupe, a half-empty tank can sometime mean that the swirl pot runs dry

I can't maintain full-throttle for more than about ten seconds if I have less than a third of a tank - throw in a right-hand bend and quite simply, I run out of fuel

You can use your spare tyre space for smaller tank......actually that's where i will put an extra tank if needed for kind of endurance race....

Yes thats where i think it will go. And the battery behind my seat.

I've also got no idea why you would want to remove the standard tank and fit a smaller one Joe? Certainly no significant weight loss to be had. Seems a lot of expense and faff for no gain?

As Nigel says, anything less than 1/4 of a tank and a combination of a hard right turn and a heavy foot on track and my car has been known to splutter on lack of fuel!

First? That's just for hill starts! Constantly keeping the taps open in 3rd and 4th will give comfortable single figure mpg returns!

I'm still extremely doubtful of the coops ability to race at anything over 60/70% of it's potential for 3 hours, without cooling becoming an issue. Be it oil temps, water or braking fluid temps?

I'd be asking if anyone else has ever done anything similar before? (And am with this comment )

The track(if this potato field can be called a track) is'nt too fast - 2 km long, full boost can be achieved in only 50 - 60% of the all distance, few slow corners......think it's enough not to overheat the fluids.
Here is the start of our last endurance race, skip first 4-5 mins - and you can see that full throttle is not over 60% of the track distance.
Lotus Elise Start Endurance M1

If high speeds achieved, there will be some aero drag reduced, if the rear area is flattered with some kind of flat plates - just flattered, no need of some advanced diffuser.....well if proper diffuser can be made there will be additional gain......
Saw one test with Alfa 156 GTA few years ago - max speed with stock floor and another test with perfectly flat surface underfloor - 15 kmh difference in top speed......aero drag in speeds above 70mph increase rapidly....