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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
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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.

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