My first tune

[SPRAYED07]

Did my first tune the other day. It was a 2001 5.3 GMC Sierra...anyone have any suggestions or care to critique...really want to learn more

[cmitchell17]

I made some changes to your tune.

First of all I am not as knowlegeble as the poeple on this board, but I am in the same situation as you trying to tune my truck.

Your PE mixture was to lean at 6400rpms which I think you should set it to a very rich mixture for saftey reasons like ovverev you motor you dont want lean. I richened it at peak torque and leaned it out again at peak hp.

I changed your o2 shiftpoints to a leaner setting which will let the motor lean out in light loads which will help save gas.

I adjusted you spark table to a spark table from a 2005+ and added timing through the fuel mixture spark correction table. A member here gave me a spredsheet that will convert the optimal timing table to your high octane spark table. Your optimal timing table is supposed to be the best timing for the engine.(Without a dyno it is hard to find out what is the best timing)

I did not mess with your transmission but if you have a stock trans I woundnt take out all Torque reduction, I would leave about at least 50%

Let me know how it goes becuase I have a relatively stock truck for now that im trying to get the most power out of.

[wait4me]

B5908 needs to be modified. you have it adding spark even when you arent in pe

[southern]

Here is my tune it is ok but it kinda has a flat spot in the low to mid range at part throttle. I am still trying to get that worked out. It is for an 04 but the only thing that is not the same should be the electronic throttle.

[cmitchell17]

Yeah your high octane table looked like a table got pasted in it on the wrong side.

[cmitchell17]

Hey southern, why is your timing so low?

It looks stock, are you just using it to compare a stock tune?

[SPRAYED07]

B5908 needs to be modified. you have it adding spark even when you arent in pe

me or the other guy?

[SPRAYED07]

Made the changes mitchell suggested to my own pick-up tonight. I still don't quite understand table B5908 and what table it adds timing to. What is the benefit to doing it this way instead of just making the timing adjustments in the high octane table? The first two files i'll post on this will be the tune that was on my truck and a log of it and the second will be with the changes that he suggested. Again thanks for the help and any suggestions

[cmitchell17]

The fuel mixture spark correction table lets more timing get added becuase as fuel mixtures increase it is able to take more timing, becuase a richer mixture burns slower so to get optimal burn it must ignite it sooner.

[SPRAYED07]

so when do you need to mess with the high octane table?