Hey guys, without getting into details I've been through quite the adventure since acquiring my Evo about a year and a half ago. The car was a mess when I first got it and I've made a lot of improvements but the car still isn't quite where I think it should be. I've tried a lot of different things but I think my peak boost and torque are both still coming on a lot later than they should be.

I just had a boost leak test done about a week before these pulls so I'm ruling that out as a problem for now. I'd like to hear your opinnions on my tune and any other thoughts you guys might have on what the problem could be. My mods are in my sig. Let me know if you need any more info to help me figure out the problem. Thanks in advance for your input!

Dyno Graph


3rd Gear Log


Timing Map


Fuel Map


WGDC Map

 

Is your wastegate actuator loose? you're pushing that duty pretty hard down low and its doing nothing.

 

you afrs are a little rich at the top end (aim for about 11.7-11.5) if you can, I'm assuming this is a standard turbo? if so I'd be looking at the wastegate not closing all the way (worth seeing if you have 1/2 hole on the arm, also the wastegate door might be worn so not forming a proper seal (but you'd have to take the turbo elbow off to check)

 

there is definitely something wrong there.. whether its a bad leak, malfunctioning wastegate actuator or 3 port setup wrong etc.. it almost looks like the timing could be off also the way the curve is at higher rpm. the maps & tune data look good at spoolup.

 

Yes stock 8 turbo with 10.5 hotside. I like keeping the AFRs a little richer up top for safety reasons.

Funny that you guys all mentioned the WGA possibly being loose. It actually fell off the day that I had the boost leak test done right after I left the shop. I turned around and went back and the guys put it back on and put a new cotter pin in but ever since then you can hear what sounds like the wastegate flapper rattling when I'm sitting at idle. I think you guys may have just confirmed the problem.

That being said, what would my next step be? Would replacing the WGA fix the problem or do I need to repalce the WGA and the hotside since it sounds like it might not be sealing properly? Also, in order to replace the hotside would I need to pull the whole turbo? If so, I guess it's time for an upgrade!!

 

chances are its just the WGA arm not tensioned properly and under boost the flapper is blowing open.

 

OK. I think I'll try to tighten that up first since that won't cost me anything

 

just tighten it and wind the arm in until there is half a hole overlap then put the arm back on and you should be ok

 

I'm gonna try to take a look at it tonight or tomorrow but I might need some more clarification on what you mean by "half a hole overlap"

Thanks for all your help and input guys!

 

he means with the wastegate arm held shut turn the adjuster on the actuator rod till it half the hole off so you have to pull the actuator rod out to get it on the wastegate arm

 

OK gotcha Thanks for the clarification!

 

sorry should have made my self a little clearer, but exactly what todd said

 

No problem man, I figured it out thanks. That thing was an absolute pain to break loose. I actually had to pull the WGA out and use some PB Blaster, a wrench and some vice grips in order to break the nut free so I could tighten it up. Once I got it broke free though it spun easily.

 

Well I tightened up the WGA about as far as it would go and here are the results. Seems like boost is still coming on a little later than it should but it's definitely improved as well as low end torque. Need to make a few more adjustments to get the top end power back I guess. What do you guys think?




Here's the comparison graph

 

looks much better now. probably needs some afr tweaking now to get it perfect