How to empty fuel tank?

[Heavy]

Hi guys,

I have done a bit of research and spoke to a few people but I am curious as to what methods people have used to empty their fuel tanks.

I am about to get my car back after having a few bits put on and being with APR I have the ability to switch tunes using the cruise stalk to higher octane files. Previously I would just run the car down and worked well enough considering how well it ran but with the new setup I am wanting to do it the right way and ill be going from 98 to 108.

Let me know your thoughts.

[Bora Sport]

Probably the easiest way is to remove the rear seat, then remove the black metal flap above the fuel pump. Then take the fuel pump out and siphon the fuel straight out of the tank. This is the way it is usually done when people mis-fuel diesel/petrol cars.

[The_Hawk]

If you've got the switching option I'm going to assume you have a 98 Tune in there too?

Just run it down to empty then fill up again?? Even if you only get down to 1/3 of a tank of 98 and fill up with 108 you end up with a mix that's about 105. I would like to think the ECU can deal with 3% variance in octane without issue.

Assuming you are impatient to play with your new toys and want to do it now... taking the fuel pump out is going to be the quickest and easiest way.

Something like this and some fuel hose will make your life much easier too.
Craftright Drill Powered Rotary Pump | Bunnings Warehouse

This is also an interesting idea:
YouTube



Another one is this video, although I'm only really interested in the hard plastic pipe that goes in first to get around the anti siphoning bits. I'm sure it would be easy enough to rig up something to test (I like the cable tie looking thing to stop you dropping it through into the tank). If this worked it likely to be the quickest and easiest way to go.

YouTube


No matter how you go, grab a couple of pictures and tell us what worked for you!

[Heavy]

Thanks for that guys!

It currently has 98 in it on the 98 tune but I am putting it on the dyno tomorrow to test both 98 and 108. I have decided to just run it down to basically empty and throw in 20l of 108. As you suggested there should be some tolerance for lower octane built into it.

Previously I ran the 104 tune using the same 108 fuel so a little 98 still left in there never made a difference. Hope it doesnt with the higher octane file lol!

[Machine]

Sorry I’m late to the party. Thanks for the link to my video, The_Hawk. I’ve done that draining for years for the same reason the OP wants to do it. Very easy and fairly quick. I’m planning a more in-depth how-to video, but for now, if you’re still interested, we can talk privately and I’ll tell you how to do it.