As you guys may know, I suspect my car is not producing the boost pressure (and hence horsepower) that it is supposed to. This is based upon the results of the recent dyno test at AWE Tuning. I believe the culprit is an incorrectly adjusted passenger side wastegate actuator rod. I had to replace it when the original one was bent upon receipt.
I am trying to get to the bottom of this and wanted to start my research by querying those with Stage 4 kits.
What boost pressure are you seeing under full-on acceleration???
I have only seen 1.1 bar so far. Should I be seeing 1.2 bar?

 

I have the EVO stage IV setup and in regular (non race) mode, I only see 1.1 bar for boost with 95 octane fuel.

However... If I go chipswitch to stage IV Race program, then I see 1.3 bar.

I wouldn't worry about it... if there is a problem; we both have it.
<grin>

Joe West

 

KPV,

Why don't you call Stephen or Todd regarding what the boost should be?

 

Ken,

I have stage 4 from IA and I see spikes to 1.2 on a regular basis...

 

I usually only see 1.1 with occasional 1.2 spikes in level 4 mode...Spikes are never maintained for more than a few secs though

 

Ken,

Your WHP to FWHP conversion on the mustang dyno brings you above the advertised 600FWHP.

According to Buddy who spoke directly to the guys at Mustang, conversion from WHP to FWHP uses a loss factor of 23-25%.

Using the lowest conversion factor (23%), you're making 602FWHP.

 

Should be 1.2 on average. The gauge can not be trusted as I have said before. Also if your wastegates have not been set they are to conservative and should be adjusted.

 

So, once I go through that shimming operation that we discussed, I will either get 1.2 more readily OR a throttle body shutdown?
THe fine line we must walk.

 

I usually get 1.2 bar and spikes to 1.3 using 91 octane

 

Kevin,
Hmmmmm. Interesting comment. My understanding is as follows. Please feel free to correct me if I mistate anything because I really need to understand this.

• If my wastegate actuator is incorrectly adjusted, I should be prematurely bleeding off boost pressure. This will result in less than optimal performance on the dyno.
• If I "tighten" it up a bit (5mm per Stephen's suggestion) then the previously bled boost will be redirected to the intake. By tightening, I am referring to adjusting the actuator rod such that the stroke of the wastegate is limited. This limitation in stroke directly limits the size of the wastegate opening and thus the amount of bled boost.

Wouldn't the throttle body be forced to shut down if the wastegate was not large enough to bleed the excess boost pressure?