Im trying to decide what wastegate spring to run in my setup. When its time to tune i will be doing both pump and race on the same day. I want to be able to run 28lbs if necessary( to reach ~550 whp) when I get tuned. What is a good starting spring that will be able to hold this much boost with a controller,

wastegate is a 38mm tial,

what are you guys using/?

 

i would use the 1.0bar spring should be plenty to get you there easily

 

The only problem that i forsee with using that spring is that the car will immediately have to start tuning at 14 lbs. And the turbo Im running will probably be ~400 whp on this boost level. Im at 10:1 compression and kinda wanted to keep power ~350 whp on pump. I know its hard to guess what boost level with make that power.

 

you should start tuning with a 10psi spring. And work your way up.

 

I guess my real question then, is will a 7-10 lb spring be able to hold 28lbs with use of a boost controller?

 

it should be able to do it on .8bar spring easily but most i seen are done on the 1.0bar and higher springs

 

since you are going to be running race gas, which is leaded, you will need to get the tial spring that is made for running leaded fuel.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Evanmb44 &raquo;</TD></TR><TR><TD CLASS="quote">since you are going to be running race gas, which is leaded, you will need to get the tial spring that is made for running leaded fuel.</TD></TR></TABLE>

I think you are referring to the actual valve. Im not gonna run race gas all the time so im not very concerned with changing the valve.

 

im pretty sure that the spring will be efficient up to double the spring rate. at that point it could start to flutter at higher RPM's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by platinum00 &raquo;</TD></TR><TR><TD CLASS="quote">im pretty sure that the spring will be efficient up to double the spring rate. at that point it could start to flutter at higher RPM's</TD></TR></TABLE>

 

I ran up to 28psi on a tial 10psi spring and the boost held perfect. I was running the greddy profec spec 2 if it helps.

 

I also run a 10psi spring and it holds boost just fine. I wouldnt go any smaller then that tho.

Generally speaking, the larger the spring, the easier it will be for your boost controller to control greater amounts of pressure.

liam