hey guys, heres a hypothetical situation a friend of mine, bob, wants to buy an external wastegate (probably a mosta 50mm 1000hp ebay one) however they only come with 8 or 10psi springs in them which is too high. the two fixes for this that bob can think of are:

1. go to a spring manufacturing joint and get them to make a spring that is weaker, or
2. remove the spring completely

bob is thinking seriously about the second option because its cheap. he's imagining that the result would be a wastegate that opens (probably to the full ammount) as soon as any boost is seen, is this the case? second thought, will the wastegate still operate without the spring, ie. the valve is still held central, diaphragm would move, etc and finally would a boost controller then be able to modify the "setting" of the wastegate?? (bob is only looking for low boost at his point in time such as 3-4psi)

cheers
Slabz

wastegate must have a spring, get city springs or somewhere to custom make it for you...

you need a spring to ovecome the backpressure from the exhaust manifold trying to push it open.. even if you apply equal boost pressure to the top and bottom of the diaphram, then the valve will still be free to move when pressure is applied to the valve.

if you applied pressure to the top side only, then sure it will push the valve shut, BUT only while you have boost, BIG trouble even making any boost with a wastegate thats wide open.. lol