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Nah there is no feedback switch for th boost sensor on the neo ecu's. You can basically disable the sensor by setting all values in the TP Load Recovery table to max, 255. And then turn off the DTC flag to stop the check engine light from coming on, but I think you still need the sensor plugged in. I'm not sure if the ecu starts acting up if it can't detect the sensor is plugged in. I have also heard the you need to put a resistor in the line if you want to remove it.

Yeah the tables name is misleading, I don't know why it has been labeled as TP Load Recovery but it's function is definatley the boost cut limit. Most tuners will just max it out as well as the airflow cut, TP Load Limit, for obvious reasons.

But like I said, maxing out the values won't eliminate the sensor from the system, just stop the ecu from cutting once boost goes over its set point, roughly about 1 bar.

I've tried to work out how TP is calculated by using values logged with the data log, I've tried lots of combinations of MAF Lookup, rpm, injection multiplier, latency, number of cylinders, etc etc but can't seem to get the same TP value the ecu shows, there must be a bit going on in the background I can't see.

I didnt think the boost sensor has anything to do with TP calculations.

Rather TP is as GTSboy said, TP load (boost cut) doesnt limit the boost, it limits the TP, if TP exceeds set value eg 110 then the cut is activated, u can run as much boost as u want aslong as it doesnt exceed the set TP threshhold

Ah yeah right, jeez I'll never get my head around all this lol. Have read all the NIStune documentation 4 times now, still know nothing :P

I don't get any TP cut, the sensor doesn't seem to affect drive-ability at all. But neither did the TCS code. I just want to get rid of the code before I take it back in for a retune because I haven't actually ever had my car tuned without a DTC which is a big no-no in tuning 101 haha. Until I can get it tuned with absolutely no errors, I can't be sure that my setup is working properly.

good to hear you've got it sorted hanaldo, now for a proper dyno run to see if it cracks the 280-300rwkw that this turbo claims to make :thumbsup:

Haha well Stao made 320rwkw @23psi, so it should crack 300 on 20psi. Biggest thing for me is getting my VCT working, cos god damn this turbo is laggy without it...

I didnt think the boost sensor has anything to do with TP calculations.

Rather TP is as GTSboy said, TP load (boost cut) doesnt limit the boost, it limits the TP, if TP exceeds set value eg 110 then the cut is activated, u can run as much boost as u want aslong as it doesnt exceed the set TP threshhold

it doesn't, and what your saying is correct for the "Load Cut (TP Limit)" table. But on the Neo RB25 there is an additional Boost Cut, that will cut the engine when boost exceeds the set point (~1bar). The table this set point is in is labeled "TP Load Recovery" for some reason. I know when Matt is breaking down the image and locating the tables he compares them to other known images, so that part of the map may have looked like a TP Load Recovery table and adopted the name.

According to page 7 of Matt's mapping guide, TP = MAF Lookup * k / rpm

And MAF lookup is the output side of the VQ map.

yep, tried that. i have also tried the calcs from the nissan patents on TP. it just doesn't work out for the values i have, though i am running a Z32 MAF.

e.g.

RPM: 5162

VQ: 47544

K: 402

using the above formula 3702 (14)

Actual TP: 43900 (171)

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