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Setting up a open loop boost controller, Issue with different weather conditions

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Hey guys, just wonder how you guys go about setting up a boost setting on a open loop boost controller (whether its a boost tee or aftermarket boost controller etc)

For example my target boost on a certain car was 12psi, Car was tuned in the middle of the day with ambient temps close to 30 degree's. Was a standalone electronic boost controller and all was well...

Customer came back later that evening and complained about the car suddenly loosing power which giving it a hard time... A quick test drive while logging confirmed it was hitting overboost cut while reaching 15psi. reving it out through 1st then 2nd then 3rd... The ambient temp had dropped alot as well as air density...

I ended up making up 2 settings in his boost controller with the second at a lower duty cycle so he could switch between them to avoid boost cut... He asked if I could just remove boost cut.... which I could, but obviously defeats the purpose...

Ive got a standalone electric boost controller in my own car which has 4 presets and im always switching back and forth to suit the weather conditions to suit my target boost.

So yeh just wondering how others work around it, especially for customers and where you might be tuning the car in the middle of summer and know the boost is going to be alot higher at the same duty cycle in winter...

Most boost control setups I've done have been using the Link ECU's internal boost control functionality, and I have had a reasonably good amount of success using a method similar to/based off what Andre wrote up years ago here: https://stmtune.wordpress.com/2011/08/08/setting-up-link-boost-control-in-5-easy-steps/

I've started using closed-loop on top of that as in some cases no matter how well it seems to work in testing there seems that there will be a day or a scenario where the real world input needed from the boost control solenoid will not be found from an open loop setup - when using a closed loop control I've found up around 10% difference in duty cycle can be required to achieve the same target boost, if you are tuning an open loop setup with stable testing conditions you'll find that 10% is a HUGE variation :/

That Link Lith posted is still imho a relevant way of configuring an open loop boost control strategy if you don't want to set up closed loop control for some reason.

If you're setting up an open loop system with no ability for any feedback you're going to need to accept that the boost will fluctuate from day to day, hot to cold, and even gear to gear. It's all about accounting for the worst case scenario when you tune the boost. I'll generally set the boost up on the dyno to whatever level I want to run and tune the car. I'll then take it out on the road though and confirm what boost I'm getting under heavy load (ie a full throttle pull in 4th gear). More often than not you'll need to remove a little boost from the controller to get back to your boost target. The upshot of this is that you're now likely to be below your target in 1st/2nd gear and you may still see an overboost scenario in cold temperatures.

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