Whipple MAP calibration

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Mar 10, 2018 | 09:34 AM

Littlefield

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Whipple MAP calibration

2016 Silverado 5.3 runs great after the SC was installed. My digital boost gauge reads funny, like 20+ inHg idle vacuum and not but around3 psi boost. Anybody know if the Whipple calibration changes the range on the MAP? If so, do you know the new range?

Thanks,
David

Mar 10, 2018 | 02:28 PM

madmann26

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Quote:

Originally Posted by Littlefield

Where is your bypass valve connected? It should be connected to the lower manifold port.

Anywhere else, it won't close properly.

I would also check to see if it's adjusted properly.

Mar 10, 2018 | 09:35 PM

Littlefield

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Thanks for the feedback. Yes, Whipple has the bypass actuator connected to the discharge side of the compressor. It’s for sure opened at idle and closed with the engine off. If anything it seems like the compressor discharge pressure would be higher if the bypass valve did not open.
I didn’t explain my measurement my measurement very well. It’s a scanning gauge that connects to the OBD2. Not sure what if anything Whippledid with the calibration, also not sure what happens when you overpressure the stock 1 bar sensor. The indicated boost reaches 2.7 psi at about 3000 rpm and never wavers as speed increases. Makes me think the sensor and gauge is at the extreme of their span and just wont read any higher. Guess I’ll have to find a different boost gauge.

Mar 10, 2018 | 09:48 PM

FFDP

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Stock MAP sensors have a linear setting of 128kpa and an offset of -0.30, and that translates to about 120kpa max reading in the scanner or about 2.5-3psi of boost.

Nothing really happens other than it not being able to read any higher than that. Though that is also were it is kinda of a problem if you are someone that actually cares about tuning. Having the computer not even know the exact boost pressure with the MAP sensor and not even tuning the VVE for boost is kinda dumb.

Companies like whipple have been doing MAF only calibrations for years though and that is the only reason they can sell them as bolt on a go kits. They just fudge some numbers so it doesn't knock itself to death and add in more fuel to keep it safe.

If you wanted your scan gauge to read boost correctly, you'd have to buy a 2 or 3 bar sensors and change the linear and offset settings in the tune file to support that. Then it will read boost. Or installing a mechanical boost gauge is required.