How To Upgrade Stock Wastegate Actuator

[Equilibrise]

I have just completed upgrading the stock wastegate actuator to a Turbosmart universal actuator with 14psi springs and thought it would be nice to let you guys know how I did it. Some modifications to the new actuator are required as our actuators are not in a straight line to the gate due to space restrictions.

First up remove the stock actuator. Some of its parts are required for the new actuator to work: actuator rod/shaft and the mounting bracket.

Next, dismantle the stock actuator: cut the ribs (careful of the loaded spring!), undo the rod/shaft retaining nut and remove the rod/shaft. Now cut the housing off the bracket to retain the bracket.

Now, dismantle the Turbosmart actuator and remove its straight rod/shaft. To do this you must clamp the housing, otherwise you will never undo the retaining nut.

The stock rod/shaft needs to be shortened 5mm on the actuator end and a new thread needs to be cut in to fix it to the new piston. I actually cut a larger than required thread on the shaft and tapped a matching thread into the new piston.

Now holes need to be drilled in the bracket so the actuator can bolt up to it with the shaft hole in the bracket lining up with the actuators shaft hole. A couple of coats of paint before it is attached to the new housing would be good.

Next, the stock shaft gets installed with the new gromet, spring base plate and springs. Now here is the tricky bit... Apply Loctite to the threads of the shaft and piston. Use a clamp or something similar to pull the piston to the shaft thread under the springs compression and when they meet, rotate the piston to wind up the shaft thread. I compressed the springs as much as required so that I could tighten the shaft as much as possible. Now remove the clamp and align the shaft as in the pic. The final alignment is to be where the blue marks on the bracket are, but only move that once you have the body assembled.

Fit the diaphram and top housing over the piston and begin to maneuver it into position before reapplying the clamp with the retaining nut looped over the clamp, ready to screw onto its thread.

This step requires a bit of maneuvering, but the easiest method I found was to drill out some holes in a piece of ply and use that on the back of the actuator to get the clamp in the right position to close the housings properly. These need to be closed completely to get the retaining nut on completely.

I already had this on mine, but you will also need a female threaded eyelet for the other end of the shaft so that the correct pre-load can be applied to the gate.

And voila, a much better wastegate which will wont leach out precious boost too early based on a 8psi spring (stock spring rate)

[scotty nm35]

Or you can simply weld a spring to the side of the stock actuator like I do, much cheaper and easier to swap springs.

I do like you ingenuity, but getting to the actuator is a pita from the front.

[joshm35]

Great write up

Edited September 15, 2013 by joshm35

[Jetwreck]

yup....great write up.

[Equilibrise]

Thanks guys

[Daleo]

How have you found performance of the new actuator?

More aggressive coming on boost- more stable?

[red_spider]

Great write up

I was literally talking to daleo about something like this the other week... Seems you beat me to it!

[scotty nm35]

I wish you hadn't ruined the factory actuator for a simple shaft Adam, I would have bought it off you as they are rare items. (mine keep going missing)

If anyone else is planning to do this, perhaps make a new shaft for it, and better would be to use a dual port actuator if possible. That way you can use boost pressure to hold the actuator closed also.

[red_spider]

I wish you hadn't ruined the factory actuator for a simple shaft Adam, I would have bought it off you as they are rare items. (mine keep going missing)

 

If anyone else is planning to do this, perhaps make a new shaft for it, and better would be to use a dual port actuator if possible. That way you can use boost pressure to hold the actuator closed also.

If anyone else was planning it just a idea but you could try using a straight shaft with a adjustable plate to get the clearance on the housings?

[SkudR33]

Or you can simply weld a spring to the side of the stock actuator like I do, much cheaper and easier to swap springs.

I do like you ingenuity, but getting to the actuator is a pita from the front.

Hey dude,

do you mind explaining what you mean??? I like the idea of being able to swap springs!

[scotty nm35]

I have made around 20 modified actuators for M35's, welding springs to the side that pull back on the same angle as the stock spring. They hold around 17psi, depending on the setup, and work quite well.

[red_spider]

I have made around 20 modified actuators for M35's, welding springs to the side that pull back on the same angle as the stock spring. They hold around 17psi, depending on the setup, and work quite well.

And you do them cheap

[Footo]

And they work!

I can vouch for that!

[Jetwreck]

The Actuator modification in any firm should be part of any turbo upgrade for these cars.

[Equilibrise]

The shaft can not be straight. If you were to make up a different bracket to move it past the turbo, then you would have to cut a large chunk out of the wheel well.

I initially bent up the shaft which came with the new actuator, however it ended up 10mm too short. I guess it would be possible to get a female to female connection to extend it though, then the stock actuator could be saved.

Before all of this I did attach a helper spring on the outside, however, I was unaware of the spring rate and after reading on other forums that they tend to break after some time, I wanted to reduce the amount of reasons why I would need to get to the turbo again. I am not all all saying that Scotty's mod is no good, but simply that I didn't believe I had it right and the desire for something more permanent.

Whichever way anyone decides to go, it is recommended to upgrade/modify the actuator, as 8psi is a little low for what most of us want out of our cars.

[Equilibrise]

Typo: "I am not AT all saying..."

[scotty nm35]

I haven't had a spring fail in over 5 years, that's a pretty good run. I can't see a 3mm piece of spring steel snapping in a hurry without outside forces these don't get, and it's easily replaceable anyway at little cost.

The Turbosmart actuator looks good, although I would rather the kinugawa one with dual ports if it fits, as it is half the price. They also come with various bent/straight shafts to custom make it to suit. I am looking into this at the moment as it has been too long without a bolton actuator upgrade for us.

[red_spider]

I reckon you did a good job and it's good to see something different

Scotty would be cool to see something easy and off the shelf

What about modifying a evo x turbosmart actuator they have a band and are 233mm long... Maybe cut the straight and shorten it to suit?

[red_spider]

Forge motorsport in the states have a large range too

But the dual ports probably would be a more suited option