INFO: 3 bar MAPs on Stock LNF base file

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Originally Posted by cobaltssoverbooster

no factory tune files with altered map data run higher numbers on the same dyno than a gmstg2 flashed into the same vehicle without moving it.
make a factory file 3 bar conversion and fully tune it....now without moving it flash a gmstg2 and copy and paste the tune parameters before. adjust the minors as necessary and i bet you 85% of the time the factory altered has higher trq output with the bonus of less non-user commanded output effects(ie: overspool control, trq nanny, corner load dampening is less........goes on)

if you were saying that and i miss read it im sorry

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lol.. I think you may have misunderstood what I'm saying. All I was saying is that (specifically speaking for the lnf. Not an lsj gms2 which is clearly a different story) if you just install the 3bar map sensors, harnesses and then copy ONLY the 3bar map sensor data into a completely stock file, there will be no power gains what so ever. All dals, wgdc, torque limiters, timing, cam tables EVERYTHING is stock, so there is no way any power can be had by just installing 3bar maps and copying sensor data over. Actually custom tuning on top of the 3bar maps as compared to the 2.5bar is obviously a completely different story, but that wasn't where I was going with what I had said earlier.

Gotcha

Another great thread! Thanks for the 3bar info!

I just purchased the GMPP LNF Turbo Upgrade from CED. I would like to tweak my tune after its installed with HP Tuners. Is this possible? I thought I read somewhere that it is harder to tune after GM re-flashes my computer. Does anyone have first hand experience with this?

Yes it's possible. The GMPP tune has more limiting factors in tables we don't have access to so it is recommended to use a stock file to modify and just add the 3bar map sensor info. In my opinion I would see if you could get a refund and just buy the plug and play harnesses. You'd save a lot of money.

^this

Thank you both for your information. I talked to Tom at CED. I have decided to send back the GM LNF Turbo Upgrade but keep the 3 bar sensors and the plug n play harness (Tom worked out a great price for me). My next purchases are the GMPP Performance Intake from CED, the next is HP Tuners and the Polished Charge Pipes from DDMWorks !!

Unless you want them for looks, save your money on the charge pipes. Waste of money if you're running the stock turbo. Not an area of restriction. Same with the GMPP intake. Looks real pretty but not an area of restriction.

Get HPT, save duckets, enyoy!

If you have a cobalt just buy a used pipe to replace the hot side over the motor. The pancake tube over the motor is the power maker of the charge pipes.

The pipes and intake tubes are for looks only. I am still getting the HP Tuner !!

Then get the GMPP first. It looks like a bazooka lol. I Can't lie. I do kind of like it. :)

Hate to bring this back from the dead, but was reading this and am intrigued by it. Now, I have been out of the LNF game since before all the new tables were unlocked (I think I was on the first beta run of 2.23, so forgive me). My brain works a lot like IAB and GMT (IDK if you guys remember me from back in the day), and control is power. So, looking into the future and I know my car will end up with a bigger turbo and probably a built motor, but for now it will not. Future thoughts though, overbuild, undertune... is there anything holding us back from putting in the Bosch 3.5 BAR TMAP sensor? I know not many folks would need this, but it would give us control over 37 psi. Thoughts?

Ring lands.

welcome back kriebs! if your built motor then the only problem will be tune clarity over 30 psi. when tuning for 40 you might have to rescale the axis to only allow idle and enough wot load to control 15-40 psi accurately. big trade off over 35psi

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Originally Posted by codename Bil Doe

Ring lands.

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Would be built and not on the stock turbo, don't worry, I am not an idiot like 3/4 of the people that come here thinking we can put a rocket booster on the car and fly to the moon.

Quote:

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Originally Posted by cobaltssoverbooster

welcome back kriebs! if your built motor then the only problem will be tune clarity over 30 psi. when tuning for 40 you might have to rescale the axis to only allow idle and enough wot load to control 15-40 psi accurately. big trade off over 35psi

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Hello again! I guess I hadn't thought of the resolution of all the tables. I think the middle of the scale might not hurt, but let's be honest, I won't be running anything up to 40 lbs, but I think 30-32 lbs on certain turbos might happen. We'll see when the time comes. That said, I was thinking purely in theory at the moment, because God knows this KO4 won't spin that high and my wallet can't afford to fix that problem just yet.

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Originally Posted by mkriebs

Would be built and not on the stock turbo, don't worry, I am not an idiot like 3/4 of the people that come here thinking we can put a rocket booster on the car and fly to the moon.

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Just making sure the polite indirect way. The k04 will hit 30+ if you want it to. :)

Anyone have the install directions for the 3 BAR MAP sensors? I seem to not find it anymore, I want the splice and solder instructions (what wire goes where).

Here you go

Fantastic, thank you!

Does anyone have the 3 bar map?

3 Bar

Linear 65.89
Offset -6.35

Be sure to look at engine diag/airflow for any other changes.

I would recommend calculating the actual Linear and Offset values of your sensor and not just using the product data values. Actual can be a good bit off and changes over time.

Build a PVC pressure chamber with a calibrated pressure gauge, that you can mount the MAP sensor too. Then use a pump or air compressor to charge the chamber while taking readings from the MAP sensor with DMM.

Here is how to calculate the scalar and offset for a MAP sensor.

1. Find the minimum and maximum voltage and absolute pressures.
2. Convert the pressures to mbar.
3. Subtract the minimum and maximum voltages to find the range, then do the same for the pressures.
4. Divide the pressure range by the voltage range to calculate the scalar.
5. Multiply the minimum voltage by the scalar to calculate the offset. Note that a positive voltage gives a negative offset.

Example for a 3.5 bar MAP sensor:

1. For a 3.5 bar data sheet:
0.5V @ 0 kPa (absolute)
4.5V @ 345 kPa (absolute)

2. 345 kPa = 3450 mbar.

3. Voltage range = 4.0V, pressure range = 3450 mbar.

4. 3450 / 4.0 = 862.5 = scalar

5. 862.5 x 0.5 x -1 = -431.25 = offset

So scalar = 862, offset = -431

Plug in the minimum and maximum voltages to check your work:
0.5V x 862.5 - 431.25 = 0 mbar @ 0.5v
4.5V x 862.5 - 431.25 = 3450 mbar @ 0.5v

If you have trouble then draw a graph and extrapolate the lines until they cross the pressure axis.

I can make a How to if there is enough interest.

--Christian

y=mx+b
b= 0v pressure offset int kpa
m= slope = (Y2 -Y1)/ (X2 -X1)

record 2 pressures. i always record one at atm so no pressure or vacuum applied and the second closer to the max voltage range of the sensor.
so slope is: (high pressure voltage - atm voltage) / (high pressure kpa - atm kpa)

pick one recorded plot and plug it into the formula with your new found M value and solve to find B.
if your not so good at math that comes to this formula:
b= y - (mx)

if you wanted to get fancy you could record 10 or so data plots and use linear regression to find a better fitting line. if your using two points then the further away they are from each other the better.

Quote:

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Originally Posted by cobaltssoverbooster

y=mx+b
b= 0v pressure offset int kpa
m= slope = (Y2 -Y1)/ (X2 -X1)

record 2 pressures. i always record one at atm so no pressure or vacuum applied and the second closer to the max voltage range of the sensor.
so slope is: (high pressure voltage - atm voltage) / (high pressure kpa - atm kpa)

pick one recorded plot and plug it into the formula with your new found M value and solve to find B.
if your not so good at math that comes to this formula:
b= y - (mx)

if you wanted to get fancy you could record 10 or so data plots and use linear regression to find a better fitting line. if your using two points then the further away they are from each other the better.

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Thanks for adding to my post I should have included the formulas.

The delta in precision decreases with more points, but using 10 would also show you if the slope is linear or if there are areas of over or under performance. I use a spreadsheet and enter the data in the table and have it plot a graph. I've see most sensors lose accuracy above 80% of its maximum range and are not consistent under 15% of there range. But this inconsistency in minor.

I'm starting to make jigs/test boxes to calibrate as many sensor as I can.

--Christian