ZS fuel tank - Is it baffled?

[arwilson80]

I noticed the petrol sloshing around in mine something awful last night (as though there were no baffles)... Anyone know?

If it is baffled then has anyone heard of them falling off / coming loose / disintegrating?

[shroonie29]

It's not baffled on the 45/ZS.Petrol sloshes about freely.Has caused some issues for PPL on track days

Shroon

[arwilson80]

So now i just have to get used to it.... :(

[Phate]

Can't say I've ever noticed it in my car.

[Dave ZS-X]

you wont notice driving on road but as shroon rightly says there are no baffles and its a right royal pain in the ass on track, hence why i have fitted a 2nd fuel pump and swirl pot.

[afcbadam]

whats a swirl pot??

[arwilson80]

whats a swirl pot??

Not 100% sure but i believe that it keeps a constant supply of fuel to the engine and it's at a more constant pressure. Solves the problem of over / under fueling when the petrol is sloshing about in the tank when going around corners at speed.

[afcbadam]

Can't say I've ever noticed it in my car.

i haven't either. but most of my driving is on a straight road. all i can here on a fast corner is the exhaust :)

[grimmy]

I get worried if i don't hear sloshing around,it means i am going to be about 45 quid less well off.:thumbsdown:

[Dave ZS-X]

Not 100% sure but i believe that it keeps a constant supply of fuel to the engine and it's at a more constant pressure. Solves the problem of over / under fueling when the petrol is sloshing about in the tank when going around corners at speed.

yeah you pretty much got it.
On track if you dont have plenty of fuel in the tank the fuel pump can suck up air and then when that air gets to the engine the engine dies and you lose power, not good for your engine and not what you want if your trying to go quickly, and of course if you just fill the tank to avoid the problem then your carrying lots of extra weight which slows you down anyway.

When you fit a swirl pot the o.e fuel pump fills the swirl pot which the secondary pump then feeds from, the swirl pot is also fed by the return from the fuel rail which normally just goes back into your main tank, any air that gets into the swirl pot gets bled back out to the main tank via return feed.

If you look at my picture then starting at the top we have...
1. swirl pot excess fuel return to main tank drain.
2.fuel rail to swirl pot feed.
3.petrol tank to swirl pot feed.
4.swirlpot supply to fuel rail (engine).

so it allows you to run low fuel to save weight and suffer no surge problems.

[stamford]

I had the very same problem on my Audi GT coupe on track, I suffered fuel starvation on hard cornering, the tank was a small one enough for a few laps. What made it worse was the system being the Bosch K-Jetronic one where it is a constant supply to the metering unit. I made a new fuel tank design where the tank was taller and slimmer therefore would swirl around eliminating starvation and air getting into the system.

Like Dave has said, if you run enough fuel for track use you will suffer unless you fit a swirl pot, otherwise you'll be running half a tank and excess weight. Defeats the object doesn't it.