Request: Tune file for LS7 MAF on LS1 C5

Hoping someone has a tune file they would be willing to share.

I'm in the process (have it installed and now adjusting the MAF table) of converting over to the LS7 cartridge MAF on my 2004 LS1 C5. I used the MAF table from a 2006 LS7 Z06 as my baseline and it drives okay (overall), but as always it's taking some time to get the table setup. If, by some chance someone already has done this, it would certainly be a big help (would at least get me closer).

Again, the vehicle is:

2004 Manual LS1 C5 w/ LS7 MAF (and air intake)

I don't have what you're looking for but hopefully can point you in the right direction. Do you have a wideband? If you do the easiest solution is to calibrate the MAF with EQ or AFR error nd you're done. If not you can log and tune the MAF with fuel trims, but I'd always recommend the wideband. Here's a method I picked up from a PDF. I take no credit for this, but have seen it posted in this community before. Hope this helps.

Quote:

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MAF Tuning ? In Work
1.) Make sure you log Dynamic Airflow vs MAF Frequency (Hz) In HP Tuners it is measured in lb/min so we will have to convert this later for the MAF table (g/sec).
2.) Go do enough driving to log a variety of MAF frequencies. You probably won't get a whole lot of data above 10,000 Hz or below 2000 Hz, but get as much as you can. Cruising on the highway is a good place for this as you can cover all rpms and a wide range of mph.
3.) Save the log run and export the data into an Excel readable format and sort the data by MAF frequency (smallest to largest).
4.) Section off MAF frequency ranges that register with the frequency points on the MAF table (i.e. For MAF table freq = 3000, you want to use the data you logged in the range of 2940 to 3065) Take the average of all the Dynamic Airflow data in this range. The reason you want to use this range is so that the average is calculated using a sort of "swing error" that straddles the calibration point itself.
5.) Once you have calculated averages for each range (this will be very tedious and take quite a bit of time, but using excel functions makes it much easier) you will have new MAF Airflow data to rebuild the table with. 1 lb/min is equal to 7.58 g/sec so do that calculation and you will derive a new MAF table.
6.) For all the calibration points that you were missing data for (above 10K Hz, below 2K Hz) you can either shoot in the dark and scale up accordingly, or if you choose to log raw MAF air readings in tandem with Dynamic Airflow and frequency, you can calculate the variance b/w your dynamic airflow and MAF airflow and scale up by the trends you see on either extreme. (i.e. If as you get closer to 10K and you notice the dyn airflow is 10% higher than the stock MAF airflow, then you can go ahead and "assume" that above 10K Hz it will most likely behave the same, otherwise you could try to log 155+ mph runs)

I know this seems like a very painstaking way to do this but it worked very well for me and using a lot of excel functions I was able to reduce the time on this project significantly. I have verified that my MAF reports almost exactly what dynamic airflow the motor sees and therefore does not cause any confusion for the trims (this other bit of business in this thread is not MAF related). Some people have tried using scatter plot functions to derive equations that will supersede any manual calculation, but having to "best fit" the curve for the logged data leaves an element for bias and human error. Manual calculation appears to be the most error free method that I can think of. Hopefully someone can come up with an easier way!

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I did the same thing earlier this year, changing to a LS7 MAF in a 2001 Corvette. You need to do some math due to the tables being different, but it works. I did verify with a wide band and made small adjustments roughly 3% in areas, similar to the method evolmotorsprt posted. After this swap I found that I had an intermittent stumble at expressway speeds, took a bit to figure it out but a laminar airflow straightener just in front of the LS7 MAF eliminated this issue of the stumble.

You will need to make adjustments to the IAT table as well, they will be off roughly 15 deg F. I had issues my first run with the IAT being maxed out right away due to the 2 wires being reversed in the adapter harness I purchased. So you may also want to verify that as well.

Quote:

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Originally Posted by Gyver-it

I did the same thing earlier this year, changing to a LS7 MAF in a 2001 Corvette. You need to do some math due to the tables being different, but it works. I did verify with a wide band and made small adjustments roughly 3% in areas, similar to the method evolmotorsprt posted. After this swap I found that I had an intermittent stumble at expressway speeds, took a bit to figure it out but a laminar airflow straightener just in front of the LS7 MAF eliminated this issue of the stumble.

You will need to make adjustments to the IAT table as well, they will be off roughly 15 deg F. I had issues my first run with the IAT being maxed out right away due to the 2 wires being reversed in the adapter harness I purchased. So you may also want to verify that as well.

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Would you mind sending me a copy of your file? I'd really appreciate the opportunity to compare with where I am. I didn't even think to check the IAT, thanks!

Sure its on a 2004 Corvette P59 PCM Tune that I've been working on for my 2001, Same values though. Hope it helps.

Isn't that the same PCM I'd have in my 2004 C5?

Interesting, our MAF tables aren't too far off from one another (mines about 10% richer across the board). I'm curious to give your values a try and see what my car does. Thanks.

It probably is the same PCM, you would have to check to be sure. Those values seem to work well for that card style MAF on a P01 or P59 controller, in my application at least. Let us know how it worked out for you, maybe it will help out someone else also.