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TurboKraft TurboKraft is offline
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Join Date: Mar 2005
Location: Phoenix, AZ
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Originally Posted by Mr9146 View Post
That makes more sense. Are you pulling sensor signal from crank or camshaft?
To clarify:

It was neither crankshaft nor camshaft sensor signal noise.

It was mechanical signal noise to the MAP and FPR, both of which come off the same port on the throttle body. Get a change in both MAP signal and fuel pressure, and you'll see changes in output.

This is the first time we've seen this phenomenon so exaggerated on a 930. Maybe it's because the ECU processor and sampling rate is much faster than on other ECUs? Maybe it's just reversion that combination of parts (CR + stock ports + 964 cams + headers + small turbo etc)? Maybe it's just because of where the signal was taken from, at the throttle body?

We've seen this on Supras on the dyno, and if the MAP signal is measured in turn at each of the four different ports on the manifold, you get noise at different RPMs.

Regardless, filtering smoothed it out considerably, and by the time the larger GTX35R turbo was fitted, it was pretty much a non-issue.

Here are final from the GTX30R dyno tests, wastegate only vs. boost control activated.

Chris Carroll
TurboKraft, Inc.
Tel. 480.969.0911
email: -
Old 06-13-2016, 10:23 AM
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