Jump to content
SAU Community

Recommended Posts

Although I know the answer more or less, I had a quick look on the site and couldn't find what I was looking for so the query goes thus... Can ya/Who has open/ed your/their stock wastegate actuator, shim/swap the spring and make it work. Cos I'm going to no matter what (almost) anyone says, I'll post results on Saturday afternoon. Ooorah for the forward slash :worship:

Edit: I should have called it wastegate acutator modification....oh well :whistling:

Edited by Room42
Link to comment
https://www.sau.com.au/forums/topic/369564-wastegate-modification/
Share on other sites

I have modded quite a few to hold higher boost, I added a spring to the side to allow easy adjustment/spring replacement. No need to cut the actuator up imo but the M35 design lends itself well to this mod.

post-63525-0-92417300-1309434025_thumb.jpg

^^^^ :blink:

Does this thing actually work? How much boost can this hold? I've seen turbos sent in with those setup and I swapped them all with high pressure actautors.

ofcorse it works... its adding preload to the gate via the use of a spring.

its crude... but it works

ok. any way, to OP yes we can build you actuators with 2x springs that holds around 18psi depending on the housing, intake and exhaust setup. Or modify your turbine housing to hold what ever boost you want it to hold.

^^^^ :blink:

Does this thing actually work? How much boost can this hold? I've seen turbos sent in with those setup and I swapped them all with high pressure actautors.

Mine held 17psi, nice and flat. Boost level depends on the size of the puck obviously so the external spring makes changes very easy to fine tune the peak.

Crude? I think its a better option than cutting the sealed actuator open as you introduce the chance of leaking which would raise boost. If the spring fails the boost returns to stock levels.

If anyone tries this, make sure the spring pulls straight into the actuator or it will put sideways load on the shaft affecting its operation. And make sure you get a tune afterward obviously.

Well that all seems good then. I reckon I'll try the outside spring idea first and see how that goes. I bought a Profec A a little while back but it was a bit rooted so the guy refunded me. The button on the front wouldn't pop back in and sometimes it held boost and sometimes it didn't. I might just get a decent boost controller shortly depending on how the actuator modification goes. Thanks for the comments and the pic guys :thanks:

Well it was a busy day so all I did was get a spring and put it on a heatshield bolt hole to the wastegate arm. With no boost control its at 8 psi. Thats a whopping 2 psi above stock. Needless to say I wound the bleed valve out a bit to make it more fun. On that subject my bleed valve has started sucking in air a few weeks ago. I'm sure it wasn't before, must be stuffed aye? I've got it t'd into the carbon canister. Any other suggestions/ideas?

By shortening the adjuster you are limiting travel, possibly causing the flap not to open enough and causing boost to spike. It doesn't add that much spring pressure either. There should be around 3mm of preload usually.

Well I cut the spring I had in half and chucked it back on. The car was on 14 psi before and it went up to 18 psi. I adjusted the bleed valve and got it back down to 14 psi again. As to be expected the turbo spools up quicker which is nice for response. I'll chuck the other half on today and see if I can get it to hold 14 psi without the bleed valve. I think it was holding about 9 or 10 psi last time with no bleed valve.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Depending on how long the car sat it is very possible for injectors to be stuck open or closed, I'd get them cleaned and flow tested. Other than that, obviously when the loom changes and the car doesn't start any more....the loom is suspect so some tracing / comparing may be required
    • Harness is for a s1 Rb25det, and it is engine and lower harness.  the old harness had broken off plugs and was in very rough condition/exposed wires and splices etc. it is not able to be put back on the car, I could visually inspect to see if they had rewired any pins on the ecu plug. The fuel pump definitly isn’t turning off it’s an external pump and very loud you can hear it. Will look at the other harness tonight, am also going to pull the fuel rail and watch the injectors spray, will update here with what I find. Pretty sure at this point it has to be something to do with injectors because car will fire up on starting fluid and cas is clicking the Injectors. Fuel pressure is steady 43psi 
    • Check the injectors flow evenly, and are actually flowing what you and the ECU think they should be flowing. If it's starting up on starter fluid, you have a fuel issue. Is it possible under cranking your fuel pump is turning off?   The harness you replaced, is that the whole engine harness? Do yourself a test, and drop the old harness on and plug it into the Z32 ECU. It's possible they've wired things different. From memory S1 to S2 is different in RB25 and you may have a wrong loom
    • I haven’t pulled the injectors to watch them spray yet but they are clicking from the cas and all of the spark plugs are wet with fuel. I’ve thought the cylinders were being flooded from the beginning and was hoping fuel pressure would fix it. Tonight I am going to pull the rail and watch the injectors spray. Don’t know how to test/diagnose if the plugs are firing in correct sequence but that should be a timing thing and as far as timing goes my car still has the half moon for the cas can only install it 1 way. And my mechanical timing is 100% correct I posted photos above. Confirmed with the balancer on and off. 
×
×
  • Create New...