Typically speaking, Would the MAP values increase or decrease
05-18-2008, 07:26 PM
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Typically speaking, Would the MAP values increase or decrease due to replacing a stock displacement LS1 engine with an LS2 402 stroker short block from the original VE table for the '99 LS1 PCM?
I am having a trouble time tuning my car. I have tried tuning the main VE table with the MAF connected and MAF not connected. I seem to get alot of confusing results. For example, If I have have positive LTFTs in FTC 6 arouns 8.0% and 8.0% for bank 1 and 2, and I edit the program by increasing the MAP values in the cells that comprise FTC 6 by say 8%, then when I test drive the car, the LTFTs are mainly uneffected. I dont get it!
Then when I try to do an SD tune by disconnecting the MAF, the engine runs like crap half the time during a data logging session (please see my other tread). How can the LTFTs jump straight from 0.0% to -8.0%? The engine runs good at -8.0%, but runs crappy at 0.0%, and the PCM is not learning between these switches. I will have 10 lines of data at -8.0%, then the next 12 lines are at 0.0% and it keeps doing this back and forth between these two LTFT values, both for bank 1 & bank 2.
I am having a trouble time tuning my car. I have tried tuning the main VE table with the MAF connected and MAF not connected. I seem to get alot of confusing results. For example, If I have have positive LTFTs in FTC 6 arouns 8.0% and 8.0% for bank 1 and 2, and I edit the program by increasing the MAP values in the cells that comprise FTC 6 by say 8%, then when I test drive the car, the LTFTs are mainly uneffected. I dont get it!
Then when I try to do an SD tune by disconnecting the MAF, the engine runs like crap half the time during a data logging session (please see my other tread). How can the LTFTs jump straight from 0.0% to -8.0%? The engine runs good at -8.0%, but runs crappy at 0.0%, and the PCM is not learning between these switches. I will have 10 lines of data at -8.0%, then the next 12 lines are at 0.0% and it keeps doing this back and forth between these two LTFT values, both for bank 1 & bank 2.
05-18-2008, 08:22 PM
#2
You cannot tune the VE with the MAF enabled. You just cant. See my instructions in your other thread. Disable the long terms and forget about them for now. Also, make sure you copy and paste the high octane table to the low octane, as thats the table it runs off in SD.
Why dont you post you tune, and a runlog? It would be much easier to help you out.
As for map values increasing or decreasing, they wouldnt necessarily do either, based solely on the engine size. It has much more to do with the cam profile.
Why dont you post you tune, and a runlog? It would be much easier to help you out.
As for map values increasing or decreasing, they wouldnt necessarily do either, based solely on the engine size. It has much more to do with the cam profile.
05-18-2008, 09:19 PM
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You have a 99 so you should also have a secondary VE table, that needs to be changed accordingly because the vehicle doesn't look at the main VE while the MAF is disabled, unless you have a newer OS. As stated previously disable the LTFTs and copy your octane tables.