Fuel levels

Author
Discussion

Mick S

Original Poster:

35 posts

194 months

Monday 5th February 2018
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Sorry but it maybe sounds silly but how do I check the fuel level in my SR3 Supersport.
I am new to Radicals and just recently bought this second hand car to do track days this season then maybe do more.
The spec says it has a 78 litre FIA bag tank, so as this is foam filled it would not be possible to dip this and there is no evidence of visibly be able to check this.
I don't want to have to brim it each time I take it out due to the extra weight, and I don't want to be the 'silly billy' sat at the side of the track having run out of fuel.

anonymous-user

61 months

Monday 5th February 2018
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I am afraid you would have to drain the tank after every session and keep track of what you fueled in. At least that's what we did.

Atom Ant

233 posts

173 months

Monday 5th February 2018
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Brim the tank and do a days running time how long the engine was operating including the warm up. Brim the tank again and see how much fuel you put in this will provide you with a consumption figure litres / minute. Then before your next outing brim the tank you will then be able to run it down to a level that suits you say half full.
Our SR3 (RSX) runs at 0.4L/Min for track days which I am told is very low and equates to the way I drive it hehe
Every now and again you should brim the tank to reset your calculation. Its a bit of a faff but gets easier as you build confidence in your consumption figures.

Mick S

Original Poster:

35 posts

194 months

Monday 5th February 2018
quotequote all
Many thanks for that.
I was just hoping there would be some easy trick. I'll just keep it brimmed at first until I can get reasonable speed and then work out what it uses per lap / minute.

ric355

215 posts

156 months

Monday 5th February 2018
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The "easy trick" is to fit a proper fuel drain if you haven't got one. Then you can use the dedicated electrical connector on the wiring harness to run the pump - this will allow the fuel to be pumped out through the drain.

Before you go to an event, pump out all of the fuel and then put a known amount back in so you've got a starting point. Put 30 litres total in for example.

Then after your first run, pump all the fuel out again. This will tell you how much you have left. Remember to take note of how many minutes you were running so you can work out a litres/minute. Don't forget to take enough empty fuel cans with you to pump the fuel out into!

Doing it this way means you don't have to run with a full tank, and you'll get a good idea of usage after your first run instead of wondering how much you've got left throughout the day.

Measure it again as you start gaining confidence as you'll be doing less coasting and earlier acceleration as you get into it.

Or alternatively, about 0.75 litres per minute is a figure I've seen written in these pages before. But measuring is better.

Mick S

Original Poster:

35 posts

194 months

Wednesday 7th February 2018
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Thanks Ric, I will check to see if it has a fuel drain system, if not I will fit one at the weekend and work on your fuel usage as a starting point

BertBert

19,703 posts

218 months

Thursday 8th February 2018
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There's nothing really wrong with filling to the brim, I doubt you'd notice on a track day. Do it for a couple of sessions to find out your usage in l per minute. Start the day full, count the minutes when you have got through 50 l put another 20l in and run for the 20 mins time and trust.

And as for 0.4l per minute, my mum can drive a radical faster than that biggrin

Atom Ant

233 posts

173 months

Thursday 8th February 2018
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BertBert said:
And as for 0.4l per minute, my mum can drive a radical faster than that biggrin
Yea I'm sure she lapped me a few times last year, i'll have to get a an engine upgrade driving