Alright the problem is very simple.

Boost is set in the 24 range, it spools up and hits the target then reduces boost right away then back up, then down, and so on. It basically oscilates.

This is extremely annoying and KILLING my power. I've tried adjusting the duty in all sorts of ways but nothing ever changes it or i severly overshoot or severly undershoot.

I've heard the MAC valve is a lot more sensative to changes then the GM or AEM. Attached are my current settings.

-Trevor

 

I've started tuning another Supra on Series 2 migrating from Series 1 and the car is using the AEM (MAC) valve. I transferred over the Series 1 settings exactly and boost hits the target, and just keeps on creeping from 18psi up to 28psi. Nothing I tried seemed to get it in control. Luckily it’s dialed timing wise that it’s not knocking or dangerous but still it needs resolved. I read a post on AEM Forums there was a problem with the error control or something so that’s probably what’s going on.

I personally run a manual in my Evo and the other Supra I’ve tuned on Series 2 is also using the same manual controller I use. He was standalone electronic but the control box had issues and for testing I said can't go wrong with a manual and no he's happy to keep it that way. I almost decided to wire in the solenoid but glad I didn’t due to the issues am seeing on this other Supra.

I think your frequency should be 31000 uS vs the 32257.6. On Series 1 it would be 31k but that probably wont help much cause I tried that on the Supra and the result was the same.

 

My guess is the feedback/error control is just not working correctly.

I think i may just switch to a Manual controller and not have to worry about it anymore. It is really annoying to need a laptop to change boost levels too.

 

That's why I went manual in my personal car. I had Series 1 controlling my boost for a long time and everytime I went to race the car out came the laptop cause boost was slightly off or I needed to adjust something. It's a real pain in the *** to dial in perfect. The manual controller (Buschur Inline) I set to 30psi over a year ago and I've never had to change it... If I need to it's so simple it's really a non issue anyway.

 

Have you had any further luck with this? I was unsuccessful getting boost control to work correctly on a Supra so we put a manual on it and sadly that manual controller isn't working right so back to drawing board. There are some other issues on that car with boost creep so that presents its own challenge.

I hope to do some testing on another Supra and a Profec B Spec 2 solenoid possibly tonight cause that car needs boost by gear now. Maybe I'll have some better answers tomorrow.

 

I gave up. Went to Manual and have had rock solid boost ever since.

 

It really is the easiest method thats for sure. Didn't get a chance to try that Supra on AEM controlled boost yet. The other Supra that we've been trying to work the bugs out of has a wastegate issue now so that took most of the night. Shooting for Saturday now so if that works out I'll report back.