Jump to content

Turbosmart Iwg75 & Over Boosting


Serangan

Recommended Posts

  • New Member
  • Member For: 9y 5m 23d

Have talked to a bloke up here with the same actuator and he has it working well with 1.8mm preload. going to leave mine like it is at the moment and leave it on the spring till next year. Shes making 366rwkw on 15ish psi on a 35c+ day so that will do over xmas, a little less preload and 20psi next year :)

Edited by 048oss
Link to comment
Share on other sites

  • 5 years later...
  • Puff
  • Gold Donating Members
  • Member For: 9y 10m 23d
  • Gender: Male
  • Location: South Australia

There isn't a one size fits all approach to this but if you wanna set it and forget it make it very light.

 

If you wanna run your boost level at the max the spring will make, you want more preload. If you're running your boost level closer to the spring pressure you want less preload.

 

If you have a free flowing exhaust you want less preload. With a factory exhaust you can have more preload.

 

With a larger wastegate you can have more preload, with a smaller hole you'll want less.

 

With a manual car you will usually want more preload, with an auto usually less.

 

With a larger turbine wheel you can run more preload, with a larger compressor side you might want less.

 

Ported housing can have more, non ported might still be sh*t even with the lightest possible preload.

 

None of this is mutually exclusive, there are exceptions to all of these, some of them mixed will be the opposite, there will be many more scenarios to consider and there is more than one way to skin a cat.

 

Tl;Dr Set it so the flap is only just closed and then wind the rod about 1/4 to 1/2 a turn more.

  • Like 3
Link to comment
Share on other sites

  • Bronze Donating Members
  • Member For: 13y 11m 3d

Maybe a better way to put that question,

 

If targeting x boost with y spring, assuming everything else being equal and correct, what are the symptoms of too little preload and too much preload.

Scenarios:

x =1 * y (I.e. boost 12 psi, spring 12psi)

x = 2 * y (I.e. boost 24 psi, spring 12psi)

x = 1.5 * y (I.e. boost 18 psi, spring 12psi)

Link to comment
Share on other sites

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
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
  • Create New...
'