Gentlemen,

I run S2 cams and HKS 7460R GTII turbo + FP 18 psi actuactor. WGDC seems a bit too high for me. It's for 1.8 bar (2.0 peak). Can you comment on this?

Thanks!

Anton

 

Have you checked for boost leaks?

 

Definitely check for boost leaks. Also check the preload on your wastegate. How much boost are you running?

 

No boost leaks!

 

I run 18 psi preload on FP wastegate actuator. Boost is 1.8 bar (26 psi).

 

What I mean by preload is that the end of the WGA is threaded and there is a turnbuckle at the end of it where it connects to the wastegate. There is a nut that holds the turnbuckle in place and there should be a cotter pin that helps hold the eye of the turnbuckle onto the wastegate. Try loosening that nut, then pull the turnbuckle off of the wastegate. Once it's off try to tighten it down (spin clockwise I think), then use a set of vice grips to pull it back up onto the wastegate.

Sorry if my explanation is confusing. If you Google it I think you can find a better explanation with pictures.

 

You need to get your baseline boost up closer to the boost level you want to run. Baseline boost is what you see if you run 0% WGDC. Even with preload maxed out on the FP 18psi WGA I found I couldn't do better than a baseline of 19 psi. I upgraded to a FP 25 psi WGA which gives me a baseline boost of 21 psi. I'm about to upgrade again to a Turbosmart IGW 75 (once I get the springs I need) so I can sell you my FP 25 psi for a decent price. PM me if interested.

 

I see what you mean. No I cannot make any more turns with a turnbuckle or it gets too short to sit on a WG flapper. Does it sound like a I have a proper preload?

 

You mean 18 psi WGA is OK for maybe 1.5 bar but not for 1.8 or 2.0?

 

It should be shorter about half an eyelet or more. Just pull it or put some air into actuator to make it extend, so you could put it on flapper.




Here is some info from Forced Performance that will clarify everything:

In the videos below we will show you 3 different settings including zero, standard, and high preload. These adjustments can be made while the turbo is in the car and should not require removal.

Zero Preload is simple it's where the actuator arm will slide on and off the wastegate arm with very little effort. The preload setting would cause the wastegate be be blown open at lower than optimal boost pressure.
http://store.forcedperformance.net/m...preloadvid.mpg

Standard Preload setting is what we recommend for the majority of applications and will allow the wastegate to remain shut at normal boost pressure around 25psi.
http://store.forcedperformance.net/m...td-setting.mpg

High Preload is what we recommend for people shooting for the stars (28PSI+), this allows the wastegate actuator to remain shut for those few extra ponies!
http://store.forcedperformance.net/m...gh-setting.mpg



Remember that setting more preload doesnt change base wastegate opening pressure that much, but it effectively restricts the overal acuator and flapper movement. That helps a bit.

But much better way to solve your kind of problem is to run higher pressure wastegate actuator (FP25psi),

- or change spring inside WG Actuator(if it is possible as in turbosmart actuators etc or DIY-ing as it its shown here http://photo.platonoff.com/Auto/2005...tuator_Spring/),

- or attach an additional extension spring to actually change pressure needed to crack your WG open. That is actually the dirtiest realisation I've ever seen, but it gives an idea how it works http://i594.photobucket.com/albums/t...n/SAM_0853.jpg



PS 2.0bar in mid rpm is fine and will produce some nice torque, but I see no point in boosting so much at high rpm on ron98. I doubt if anything more than 1.6 will make any more power up top. I would set it to 1.9bar tapering to 1.5 to make it work in its efficiency range if you are on ron98-110. If you spray meth or water, then you can try going higher boost up top. Otherwise its just stressing turbo, building up backpressure and heating the intake air.

 

You shouldn't be able to just slide it on and off like Biggy points out. You'll need to tighten it down and then grab it with a set of vise grips and pull it back up and slide it onto the wastegate. It's a little tough to do but you should get it.

 

1) Thank you for detailed clarification! I'll do this. Because for now I can shake the arm on the WGA with hand and I beleive it's not going to happen if installed properly.

2) No!! 2.0 bar is a peak with 1.8-1.9 during mid-rpm and going to 1.45 bar to the 8000 rpm.

 

Clear! I'll fix this and see would it change anything (hope it will).