Evo 9 stock turbo, built block, 3" exhaust, megan o2, intake.

Grimspeed 3 Port EBC and Omni 4 Bar Map

Using Tephra v7 psi based boost control and Raptords guide for setting it up, I havent been able to control my boost. All the error correction is zeroed out as well as "wgdc=100% under this load" is zeroed out.

Ive set the global boost control types to psi.

In all gears I have had problems controlling it with the "Main Map Wastegate Duty" I started around 50% in all cells did some tweaking after pulls at first it started to seem like the changes had some effect, but I have went all the way down to 10% wgdc and I cant get the car to boost under 25 psi in my logs and guage. I'm shooting for 21 for now. Can't even get it down there. Anyone have any ideas? Is there a common cause for this? Thanks.

 

Have you logged WGDC to verify you're running the WGDC you think you're running? I had made changes to main map WGDC but switched to alt maps once which confused me for a while about why my boost was off by so much.

 

ok i will try that real quick. found it in evoscan.

 

oh one question, what should TPS WGDC Correction be set at? does it matter?

 

the log says im running 10% which is what i have it set to.

let me add some stuff. In 4th+ gear it wont go under 25psi. in 1-3 I can get it down to 23-24. if i have my wgdc set high say 75% i overboost alot I would say 30psi. so it seems there is some control.

 

Is it possible you have a 25 PSI wastegate spring?

 

i just checked to see if everything was hooked up right. i am at a loss. could the ebc be bad or my wastegate?

 

Hm you could try taking the 3port out of the equation to see. Connect the turbo directly to the wastegate instead of having the 3port between the two, and see how much boost you run then.

 

ok i hope i did this right. i connected the wastegate hose directly to the turbo outlet.

it boosted to around 25, reading the guage, the guage is accurate. then tapered off.

so do i need a different spring or adjustment?

 

I'm not an expert with wastegate adjustments, but you may be able to adjust the preload on the WG arm to have it open at a lower boost level.

 

man you have been brilliant. thanks for all the help. its all making sense now. glad i learned some stuff today too. i'm actually going to try that. ill report back once i have time to!

 

good luck!

 

driving to work this morning. still had the line going from the wastegate to turbo outlet. when i am in 3rd gear and very low speed and i go wot. it will eventually reach full boost at only around 20. same in 4th gear. if i 1st through 4th gear quick shifting it will boost to 25. is it supposed to do that.

 

Possibly wastegate sticking closed? What did you set the preload at?

Set the preload to allow the WGA actuator arm to easily slide onto the pin and rerun the tests...that will allow the WGA to open quickly. If it does not then you got something wrong with the WGA or the spring in it is way too stiff ( 25 psi or more)

Make sure the turbo outlet hose is connected to the WGA directly for this. then report back.