Tial 38mm wastegate with only one spring?

[wee-jo]

So the garage working on my car waas setting up the wastegate to take it for a spin. They noticed that it only had the one spring. The spring was a large green one, which, judging by tial's wastegate spring graph is .9 bar.

Should there be a small and large spring or just the one spring? The model of wastegate is the f38, the previous model down from the new v band shape one.

 

[markostarletturbo]

Not sure tbh i know i have a 1 bar tial spring in the cupboard i have a zisco wastegate the large spring from the tial fits the zisco

 

[Texx]

It depends on the spring pressure you want to use.

If you want a wastegate spring pressure of 0.9BAR then you'd use just the one large green spring, however if you wanted to run a spring pressure of 1.3BAR you'd use the 0.9BAR large green spring along with the 0.4BAR small red spring to bring the total spring pressure up to the desired 1.3BAR. Likewise if you wanted to run a spring pressure of 1.1BAR you'd use the large yellow and small red springs together, if you wanted to lower the spring pressure to 0.7BAR you'd take the small red spring out and use the large yellow spring on it's own.

So in answer to your question, no you do not need to use both a small and large spring together unless your looking to run a spring pressure of more than 1BAR.

 

[wee-jo]

It depends on the spring pressure you want to use.

If you want a wastegate spring pressure of 0.9BAR then you'd use just the one large green spring, however if you wanted to run a spring pressure of 1.3BAR you'd use the 0.9BAR large green spring along with the 0.4BAR small red spring to bring the total spring pressure up to the desired 1.3BAR. Likewise if you wanted to run a spring pressure of 1.1BAR you'd use the large yellow and small red springs together, if you wanted to lower the spring pressure to 0.7BAR you'd take the small red spring out and use the large yellow spring on it's own.

So in answer to your question, no you do not need to use both a small and large spring together unless your looking to run a spring pressure of more than 1BAR.

Thanks Texx for clearing that up.

So if I wanted to just run say .6 bar on the wastegate just now would I have to by another spring or could I adjust the .9 spring to run .6 bar? Alternatively could I adjust my boost controller to .6 bar without the wastegate spring over boosting to .9 bar?

Just a bit confused with the whole process.

 

[gorganl2000]

you cant run lower pressure than the spring installed

if u want to run 0.6bar...then the 0.9bar spring is too much
you need to buy a 0.6bar spring and install it

 

[Texx]

The wastegate spring sets the minimum boost pressure you'll be able to run, so with a 0.9BAR spring you will not be able to run any less than 0.9BAR (although after some pressure drop through the IC you boost gauge will probably read a little less). A boost controller, whether it be mechanical or electronic, can only be used to increase the boost above spring pressure. However there is a limit to the amount of pressure increase a boost control can reliably produce, the general rule is to use a spring pressure that is rated to at least half the pressure you want to run using the boost controller. For example if you want to increase boost to 1.2BAR by using a boost controller then you should have at the very least a 0.6BAR spring in the wastegate, this gives you the opportunity to run 0.6BAR low boost and 1.2BAR high boost, however if you will never have the need to run 0.6BAR you would see a more reliable boost control from using say a 0.9, 1, or 1.1BAR spring. Basically you need to decide on the minimum boost pressure your going to want to run and then fit a wastegate spring that is rated at that pressure, but then also keep in mind that you'll be limited to a maximum of double the spring pressure when you decide to up boost by using a boost controller. Once you reach that maximum limit a higher spring rating is required to maintain reliable boost control.

 

[wee-jo]

The wastegate spring sets the minimum boost pressure you'll be able to run, so with a 0.9BAR spring you will not be able to run any less than 0.9BAR (although after some pressure drop through the IC you boost gauge will probably read a little less). A boost controller, whether it be mechanical or electronic, can only be used to increase the boost above spring pressure. However there is a limit to the amount of pressure increase a boost control can reliably produce, the general rule is to use a spring pressure that is rated to at least half the pressure you want to run using the boost controller. For example if you want to increase boost to 1.2BAR by using a boost controller then you should have at the very least a 0.6BAR spring in the wastegate, this gives you the opportunity to run 0.6BAR low boost and 1.2BAR high boost, however if you will never have the need to run 0.6BAR you would see a more reliable boost control from using say a 0.9, 1, or 1.1BAR spring. Basically you need to decide on the minimum boost pressure your going to want to run and then fit a wastegate spring that is rated at that pressure, but then also keep in mind that you'll be limited to a maximum of double the spring pressure when you decide to up boost by using a boost controller. Once you reach that maximum limit a higher spring rating is required to maintain reliable boost control.

ok so the only reason i want to run .6 bar is because i'm running the engine in with a tdo4. So for this process should I stick with the .9 spring or change it for a lower rated spring?

 

[Texx]

If your engine management system isn't mapped to run a TD04 at 0.9BAR then it would be better to use a 0.6BAR spring, however you will still need to have the fuelling and ignition advance checked before you go driving the car about.

 

[wee-jo]

If your engine management system isn't mapped to run a TD04 at 0.9BAR then it would be better to use a 0.6BAR spring, however you will still need to have the fuelling and ignition advance checked before you go driving the car about.

Ok thanks for your help texx, rep added.