t28????

[tubby5]

should my full t28 spin on idle???because sometimes it does and sometimes it doesnt:confused:(its also a brand new unit 0 miles on it)

[jure]

It all depends how short actuator arm is. If you set it (for example) at 20 psi it will spin but if you set at 12 psi it wont. Hope you got the point...

[Scoff]

It all depends how short actuator arm is. If you set it (for example) at 20 psi it will spin but if you set at 12 psi it wont. Hope you got the point...

not sure how that would make any difference, it's shut either way.

tubby, thats normal, it might just spin a little but it shouldn't take much effort to stop the wheel by hand. it should spin when you give it some revs.

[jure]

Well, the wastegate "button" isn't always completely blanking exhaust gases hole (this sounds funny). On such big turbo it is very likely that it won't spin at all on the idle...

[Ryan p]

my t28 spins very slightly at idle

[Scoff]

Well, the wastegate "button" isn't always completely blanking exhaust gases hole (this sounds funny). On such big turbo it is very likely that it won't spin at all on the idle...


Well no, thats wrong sorry. the wastegate is always shut at idle. If it isn't then it means you have less than no preload on your actuator, which just wouldn't work at all. You have to stretch the actuator to hook it on to the penny remember.

[tubby5]

my mind is now at rest:)

btw scoff its almost ready for the map to be tweaked;)just need a screamer pipe and a turbo support bracket fabricating:)

[Scoff]

my mind is now at rest:)

btw scoff its almost ready for the map to be tweaked;)just need a screamer pipe and a turbo support bracket fabricating:)

It will go much better I'm sure :)

[Mart]

Well, the wastegate "button" isn't always completely blanking exhaust gases hole (this sounds funny)

Aii, it's hilarious....ly incorrect comment.

[jure]

I'm talking about situation when you are fitting your turbo not when everything is placed in its place. For dear god i know that there is enough vacum on idle to close the wastegate completely... I was trying to explain situation similar to procedure of "running in" turbo for the first time.

[Brigsy]

Vacuum doesn't close the wastegate on idle, its closed on its own with the preload of the actuator as scoff said..

[Nick k]

Vacuum doesn't close the wastegate on idle, its closed on its own with the preload of the actuator as scoff said..

England 1 Croatia 0 :D

[jure]

England 1 Croatia 0 :D

:laugh:

Sorry, don't get quite this term preload....:sad:

[Scoff]

pre-load is the amount of effort it takes to hook the actuator arm onto the waste gate, so weather you have 12psi or 20psi set the waste gate is still closed at idle :)

[Ben]

:laugh:

Sorry, don't get quite this term preload....:sad:
spring pressure holds the waistgate shut until pressure acting on the diaphram overcomes the spring and opens the gate.

[jure]

pre-load is the amount of effort it takes to hook the actuator arm onto the waste gate, so weather you have 12psi or 20psi set the waste gate is still closed at idle :)

OK. Thanks for explanation. This 12 and 20 psi was just (wrong) figurative explanation :D. My theory was related to the situation when actuator arm is stretched to that point when pre-load cannot pull that much to close it completely. Does this make any sense???

p.s. I'm not good in theory. Give me the wrench...

[dave j gtt]

dont worry about it jure , guys on here just step in to make sure people are getting good correct advise, and will comment to assist members with there topic, or to correct somone who has there wires crossed or are incorrect. either way it all good if you dont comment and read an ask questions you dont learn ;)