+6 PSI Calibration Below +6 PSI of Boost

[arnoldod]

I'm working from home the last 3 weeks as COVID-19 infections spread rapidly in my country so I spend my free time try to compare Flashpro calibrations.

Interestingly I find stock equivalent calibration of 2017 Civic 1.5T base calibration, which should equivalent to the stock calibration.

I compared with +3 PSI and found TC Maximum Pressure indeed 3 PSI higher in +3 PSI calibration.

However, the result is different when I compared with +6 PSI calibration. The boost difference between +6 PSI and stock equivalent calibration was only +4 PSI. I compared this between +3 PSI and +6 PSI calibration.

Please see the screenshot below:
Stock equivalent calibration:


+6 PSI calibration:


I checked +9 PSI calibration and it showed +6 PSI boost, instead of 9.

Flashpro Firmware version : 3.5.5.0

Could Hondata please explain the differences?

[arnoldod]

Correction: +9 PSI boost calibration TC Max Pressure was +8 PSI

[Hondata]

What vehicle are you testing in? Can you provide datalogs?

There are multiple tables that limit the boost so we usually alter all but one in the stock equivalent otherwise people have trouble adjusting the boost. But if you give specific examples we can look at it.

[arnoldod]

What vehicle are you testing in? Can you provide datalogs?

There are multiple tables that limit the boost so we usually alter all but one in the stock equivalent otherwise people have trouble adjusting the boost. But if you give specific examples we can look at it.

I was comparing Civic 1.5T US 2017 MT calibration equivalent to stock vs. Civic 1.5T US 2017 MT +6 PSI & I was comparing TC Maximum Pressure.

Max boost of stock equivalent TC Max pressure was 16 PSI and max boost in +6 PSI is 19.9 PSI, which means +4 PSI instead of +6 PSI. I compared stock equivalent vs. +3 PSI and found the boost difference indeed was 3 PSI.

Logically speaking, +6 PSI calibration should give approximately 22 PSI of maximum boost.

I attached the calibrations for your reference.

It would be great if Hondata could explain what does +6 PSI mean because the boost difference between +6 PSI and stock equivalent was approx. +4 PSI at the top RPM.

I created my own +6 PSI calibration and see maximum boost slightly higher than 22 PSI but still lower than 23 PSI.

I would prefer to run +6 PSI calibration provided by Hondata than my own custom tune given the +6 PSI calibration really gives +6 PSI of boost compare to stock, which should max out at around 22 PSI.

[Hondata]

Are you testing in a vehicle or just comparing the calibrations?

The calibrations were developed to give the noted change in boost. If you give examples with datalogs then we'll look at it.

[arnoldod]

I don't think you need datalog to identify that +6 PSI is not actually a +6 PSI. You can compare TC Maximum Pressure tables of the stock equivalent and the +6 PSI calibration to identify that +6 PSI calibration was actually only +4 PSI.

I'd suggest Hondata to change the calibration name to the actual additional boost just like you name +3 PSI calibration to avoid misleading Hondata customers.

Your +6 PSI calibration delivers less than +6 PSI (approx. +4 PSI) unless you are saying Honda were lying about Civic 1.5T peak boost in their website, which clearly stated 16.5 PSI.

+6 PSI boost should delivers approx. 22.5 PSI of peak boost instead of 20.

[Hondata]

You absolutely need to datalog the boost because otherwise you are at the mercy of every assumption you are making.

Honda's claimed maximum boost is not accurate. Sometimes they list the maximum boost the vehicle will see under adverse conditions (high IAT, a lot of retard). For other vehicles the number is from a different model.

There are many other tables that the ECU uses to determine boost other than the one table you are looking at. Also you're looking at a pressure ratio table, which is not the same as boost.

[arnoldod]

Honda's claimed maximum boost is not accurate. Sometimes they list the maximum boost the vehicle will see under adverse conditions (high IAT, a lot of retard). For other vehicles the number is from a different model.

There are many other tables that the ECU uses to determine boost other than the one table you are looking at. Also you're looking at a pressure ratio table, which is not the same as boost.

Sorry, I waited until I was able to find good timing to datalog a stock calibration at near maximum RPM.

My finding is Honda's advertised boost is different with OBD II reading, which could happened, so I agree with you that Honda may list the maximum boost based on several conditions that only Honda knows.

I cannot push RPM further because I did the datalog on the road instead of dyno.

Based on datalog, maximum boost is around 12.6 PSI, although I notice the boost reached 14 PSI in less than 1 second.

I assumed pressure ratio table was the same of boost after I watched your YouTube video titled "FlashPro Civic X Training".