What is the max safe height to shim a stock wastgate with out getting coil bind?
I want to help my wastgate hold higher boost longer by shimming it. I read that 4mm is good, but can i go a bit thinker? i use a Greddy profec B boost controller and since it controls boost perfectly i want to shim the WG as much a safely possible to help reduse boost faid in the higher rpm's.
Thanks

 

How exactly do you shim it? I understand you are making the spring apply more pressure as to build more boost quicker, but how is that physically done?

 

No, shimming the wastegate will not have your boost build quicker. That's because at low-RPM, the wastegate's completely closed anyway. The turbo-lag limitation is due to insufficient exhaust gases and pressure to spin up the turbo. It will however, allow your wastegate to maintain that max-boost longer into the high-RPM ranges.

Here's how you shim a wastegate:
<a href="http://forums.rennlist.com/forums/ultimatebb.php?ubb=get_topic&f=18&t=000541" target="_blank">Topic: Dual Port Wastegate Question </a>

Someone mentioned that bicycle chainring spacers are perfect for shimming the wastegate. They fit the bolts perfectly and come in a variety of thicknesses. I wouldn't go beyond 5mm total though...

 

[quote] I wouldn't go beyond 5mm total though... <hr></blockquote>
So is 5mm still in the safe zone, or should i just go for 4mm or 4.5mm?
Or maybe i could just change the sring with a new spring rate for 1 bar! does that existe for are wastgate, aftermarket wastgate have the option of different spring rating. Since i don't plan on going past the 300rwhp mark i think i should just make my stock wastgate perfect for my application!
Does this make sence...
Thanks

 

I guess the deal is that you can shim the wastegate in place. If you're going to the trouble of removing it , then just replace it and get something more adjustable and able to hold higher boost levels ( if that's what you want).

 

I don't see how it would be possible to shim the wastegate in place. If that were the case I would have shimmed mine long ago. Once I started breaking studs I put the project on the back burner.

 

It was actually pretty easy. I disconnected the support bracket from the torque tube housing or whatever it's bolted to. Then I removed the allen bolts holding the diaphragm housing to the hotside. Pulled the bolts out, slid the spacers in (this took a little while) and reinstalled the bolts. It helps that I have small hands (hey, no jokes). When you do the job with the wastegate in place you don't have to mess with the studs.

 

Hmmm, maybe I'll take another look at it. I couldn't easily get to the support bracket bolts. If you've done it is obviously possible. I guess it didn't help that I was attempting this after replacing my motor mounts (I was tired and frustrated at this point so lost interest quickly).

 

It's not too bad with a extension and u-joint. You just got to hold your mouth right.