Club G40 Forum

Technical => Turbochargers => Topic started by: dub-disaster on January 30, 2013, 04:04:31 pm

Title: acutator springs
Post by: dub-disaster on January 30, 2013, 04:04:31 pm
I've currently got a forge actuator and had my car mapped for 22psi on a red spring boost response was great nice and fast.
I want the option of a low boost setting so i have now setup an electronic boost controller. but to active the low boost setting i have had to change to the blue spring.


If i switch the boost controller off and add preload to the blue spring to obtain 22psi should i have the same boost response as if i was using the red spring ??
Title: Re: acutator springs
Post by: Yoof on January 30, 2013, 04:31:03 pm
Yes, although I doubt you'd be able to wind enough pre-load onto the actuator rod with a blue spring to reach 22psi.

Defeats the point of having a boost controller though...  ???
Title: Re: acutator springs
Post by: Andy on January 30, 2013, 06:44:20 pm
Depends how weak the blue spring is, you may end up getting a bit of an overshoot of boost - which if it's bad enough could cause a touch of pinking/lean running.

Also if you've had to pre-load the actuator shitloads to get 22psi, you might find that the waste gate never quite fully opens any more - which means you risk boost creep at high rpm.
Title: Re: acutator springs
Post by: dub-disaster on January 30, 2013, 09:02:59 pm
just trying to see what's the best setup realy. I can run over 22psi early with the blue spring i thought it was weaker than that but i set it up with roughly 3/4 amount of adjustment used to add preload and i was running around 24 psi.

i turned it down to roughly 1/4 of available preload and now obtain roughly 11psi and was using the etc to boost that up to around 20psi.

What i would idealy like is the boost response of the red spring but with the option to lower the boost. Although from what Andy is saying i might just be better off fitting the red spring and using my right foot to control boost.

Just wanted the low boost for when its wet.

Its worth noting made a new brake for my actuator wick let me "clock" the turbo further to alleviate some clearance issues i had this may be why Im able to gain more preload than standard.

To clarify Although i can use the blue spring and the etc to obtain a lower and higher boost setting. with low boost i will more than likely get boost creep as i did before. and high boost is likely to cause more overshoots due to the weaker spring.

Is there a better way to obtain two boost setting for example using the red spring with little preload. Or is it best to forget the ebc completely and put the red spring back in?