Re:Wastegate springs

[pjwales@magicnet.net (Peter Wales)]

I have been following this thread with interest. Changing the spring to get
more boost is the accepted way of increasing the performance of the car and
to ensure the fuel does not cut out, over riding the fuel pump cut out seems
to be a workable bodge. 

I am very nervous of things which can endanger my safety and also give the
insurance companies an excuse not to pay out and therefore would not
recommend this mod, even with the wiring through the oil pressure switch.

May I suggest wiring a boost pressure switch in series with the fuel pump as
a solution which would be safer? The switch type would have to be normally
closed and capable of carrying about 20 Amps to be reliable and of course it
would have to be adjustable to cover the range of pressures required.

As far as the working pressure is concerned, remember you are trying to
avert disaster if a diaphagm blows. In this case  the Audi turbos will
develop a boost pressure of about 30-35 PSI easily and this is all the
switch needs to be set at. There will be large pressure pulses in the line
so setting the pressure at 1-2 lbs over the max working pressure will cause
problems.

Just a thought


Peter Wales