Hi all,

So the mighty magna was taken for a spin around a racetrack and as the fuel level started to drop the car started surging after the exit from cornersdue to what appears to be a lack of fuel going through the pump. (fuel starving). I'm told the usual fix for this is a surge tank.

Now I do have stock suspension so I'm getting alot of suspension travel and heaps of understeer & body roll, so I'm wondering; does most of the surging that comes with having less fuel in the tank (1/3rd or less) settle with stiffer suspension?

If the surging doesn't decrease with stiffer suspension, and I want to return to racetracks in the future, then are there any magna specific surge kits or will I need to use generic/universal ones?

Cheers all!

The cause of the starvation is surging in teh fuel tank - the fuel goes away from the pickup. Stiffer suspension will not change this. The only way os to install a surge tank so that you have a temporary supply of fuel when the pump is being starved.

While you're there get a baffled sump made.

Thanks for that.

It definitely seems that was the case as the surging only occured when the fuel level had dropped to about 1/3rd of the tank.

I was just thinking that due to the stock boaty suspension that has a lot of travel, the fuel is sloshing around and moving away from the pickup. Stiffer springs and a rear sway bar would reduce much of the body roll, less travel/shifting of weight and less understeer. Could that be enough to reduce the fuel from sloshing away from the pickup.

If I need a surge tank - what are the costs for the parts? Labour will be free as I'll do it myself. Are there any tanks that could fit under the boot floor? Don't want to take up anymore space in the boot (sub and log tank take enough as it is.)

Thanks heaps for the respnse mate

shouldn't matter how boaty your springs are, the faster your car changes in momentum around a corner the more the water will move. a baffel in your fuel tank should help this.

It was terrible in my old magna before changing the suspension to sportier stuff and it was terrible after. A baffled tank or external surge tank is the only way to combat this

Canyou swap a normal tank for the Ralliart tank...That tank is baffled..

If you stiffen the suspension it will help, but only if you go the same speed you are going now. With the stiffer suspension you will be able to go faster around corners and will be back to square one.

And this stops the fuel from going from one side of the tank to the other??? How....????

You might want to rethink that, the lateral G's will still act on the fuel, no matter how flat the car is...

The only real descent solution is to install a surge tank. Keep the tank more then half full is not always the best option. Surge tank can be brought or made. Best to get one made of alloy to suit your needs. If you know someone that can weld alloy that's even better as you can cut the alloy and get them to weld it. You set it up with an external fuel pump pumping from main tank to the surge tank. Once surge tank is full it will then overflow back into main tank keeping the surge tank full always. You need a surge tank, fuel pump and hoses and fittings. Work you rough costs out from there. Even worth talking to mechanic and getting his oppinion and getting him to price the job drive in drive out and weigh up your cost options.

Canyou swap a normal tank for the Ralliart tank...That tank is baffled..

Would be a cheaper option but rare as hens teeth

And this stops the fuel from going from one side of the tank to the other??? How....????

You might want to rethink that, the lateral G's will still act on the fuel, no matter how flat the car is...

There are 2 forces acting on the fuel when cornering. Lateral acceleration and gravity due the car being on an angle to the ground.
If the car stays flat rather than tilting in the corner then the gravitational force will be acting perpendicular to the bottom of the tank rather than at angle which pulls the fuel to one side. The g force due to lateral acceleration will still be pulling the fuel to one side however.

My TJ Exec had this Problem but my TL VR doesnt