Wastegate mods.

[corsair231]

Any benifit to making the wastegate actuator rod adjustable to change baseline boost settings? It's a pretty common practice on other turbos but I've not seen anyone here mention it.

 

[WFO-TSi]

You mean something a little like this? There is also some info here that addresses your question about benefits although it doesn’t really address doing this to raise base-line boost settings.

Forced Performance: FP DSM 17psi DSM T25/T28 Actuator

 

[99gst_racer]

Any benifit to making the wastegate actuator rod adjustable to change baseline boost settings? It's a pretty common practice on other turbos but I've not seen anyone here mention it.

Most of us just use a valve (boost controller) on the vacuum line.

 

[corsair231]

It would be most benificial if you wanted to leave the factory boost controller in charge. I can see where a mbc would negate the benifit unless you could adjust the preload to stop the flapper bounce the article talked about

 

[99gst_racer]

I can see where a mbc would negate the benifit unless you could adjust the preload to stop the flapper bounce the article talked about

Well, for preload, it would be as simple as using a couple of washers to shim the actuator at the mount.

 

[JusMX141]

Well, for preload, it would be as simple as using a couple of washers to shim the actuator at the mount.

But on certain turbos (the T25/T28 for example) this is impossible because of where the actuator mounts on the backside of the compressor housing.

I've done it before to T25 actuators. You'll need a 1/4" fine-threaded thread die, and a 1/4" fine-threaded barrel adjuster available at most parts stores. Make sure the barrel adjuster is threaded right-handed on both sides....finding a left-handed thread die is impossible. Then:

-Cut the actuator rod wherever you want the adjuster to mount.
-Remove an additional 3/4" to 1" from the rod, depending on how much adjustment you're seeking.
- Use the die to cut threads onto the remaining portions of the threaded rod.
- Install the barrel adjuster to the side of the actuator arm with the vacuum diaphragm, then thread the end with the loop that connects to the wastegate lever into it.
- You can then thead the end with the loop that connects to the wastegate lever in or out to achieve a desired setting.

The only issue is that because both ends are right-hand threaded, you'll need to remove the actuator arm from the lever everytime you want to make an adjustment instead of just turning the barrel like you could if one end was right-handed and one end was left-handed.