Cam Only Project(DYNO Numbers Added!!!)
First off let me say that the tuner is a friend, and has tuned roughly 6 cars and is by no means an expert. He has HP tuners and has the program down, but I'm sure a more knowledgeable tuner would not have run into the problems we did.
Idle was stuck between 17-22AFR... No mater what changes he made he could not get the idle down into the 15's... We weren't sure if this was due to the cam but it was quite frustrating. This was also the issue with part throttle, it was very lean around 20-25 until you stepped on it a bit... Maybe some one can chime in with why no fueling could be added... There was no knock present but it was just lean...
He made a few changes and we started doing WOT tuning and it went great! There were no fueling issues once we got into the WOT pulls. After 3 pulls we dialed in the AFR to about 12.6-12.8 throughout WOT.
The numbers far exceeded our expectations and I couldn't be happier with the tune and results.
The first graph compares the bolt on pulls to the cam pulls. Let me know what you guys think.
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Do you have cats? Where was the wideband for the idle tuning?
Are trims turned on still? If so, what were the trims saying? If your PT was that lean, your trims would be maxed at 25%. Were they?
Do you have cats? Where was the wideband for the idle tuning?
Are trims turned on still? If so, what were the trims saying? If your PT was that lean, your trims would be maxed at 25%. Were they?
I'm honestly not sure what the trims were at. He said once we moved to the PE table the trims worked themselves out and was great. We tried unplugging the MAF and still had the same lean idle/cruise problem. The faster we went on the dyno and the higher the gears it richened up... It was really only an issue at idle and gears 1-2... But no matter how much fuel he added at idle it would register almost in the 20'sAFR and cruise in 1-2nd gear.
I'm honestly not sure what the trims were at. He said once we moved to the PE table the trims worked themselves out and was great. We tried unplugging the MAF and still had the same lean idle/cruise problem. The faster we went on the dyno and the higher the gears it richened up... It was really only an issue at idle and gears 1-2... But no matter how much fuel he added at idle it would register almost in the 20'sAFR and cruise in 1-2nd gear.
Also, that bold scares me a bit. Fuel trims are only used when out of PE and in closed loop, so of course in PE the trims are going to be 0%.
A cam in the 232/234 range is easy to tune at idle. Only use a wideband to tine idle and PT if you can put it higher up stream in a bung. He should have been using the fuel trims to dial it in.



