SCT Tuning

[illSHOyou]

Hey Paul, Couple of questions...

I really believe that my transfer function maybe off. Right now I am flowing 23.5 lb/min air at 6100 rpm. The STFT are commanding .86/(12.59:1) AFR.

Car starts at .82 around 2000 rpm and steadily moves up to .86 at 4000 rpm.
STFT .86 is commanded from 4000 rpm on....

23.5 lb/min air should be at least 235 hp at the crank. The car has some pretty good mods at this point and dynoed 219 corrected whp on a mustang dyno at school w/ stock tune. Car currently has a xcal3 with unknown tune.
I know fans come on at 206 degree/commands a leaner WOT than stock/IMRC open 2,200 rpm/trans TCC mods/More drawn out shifts.

As far as timing goes it easily presues low to mid 30's degree when the engine is around 190 degree F from 4000 rpm on. At redline I have recorded 40 degree advance on a couple of data logs untill the car gets into the 200 degree and starts pulling timing.

Too me, the transfer function has to be off. That 23.5 lb/min seems fit for a stock 235hp v8 SHO.

[SHOZ123]

Do you have an A/F gage? Also tune the A/F in 1st gear only. There are A/F modifiers for 2nd and 3rd gear.

[illSHOyou]

Originally Posted by SHOZ123

Do you have an A/F gage? Also tune the A/F in 1st gear only. There are A/F modifiers for 2nd and 3rd gear.

Not yet, Thats next on the list of things to get...
I do have the data logs. I will try to either post or email them to you.

Can I attach them to the forum somehow?

[SHOZ123]

Without an A/F gage then just going by the commanded values is not realistic. No way should you be trying to modify the MAF curve without one.

[illSHOyou]

Originally Posted by SHOZ123

Without an A/F gage then just going by the commanded values is not realistic. No way should you be trying to modify the MAF curve without one.

I don't yet have the capabilities to mod the pcm. Just trying to interpret the data and gain a understanding of what this tune I have acquired is doing. I have reverted back to stock again and while the bottom end is lacking it has more pulling force above 4000 rpm. I would imagine the PCM should be calling for the stock WOT enrichment of .75 and probably is enough fuel for safety if the transfer function is off.

I like the trans mods on the tune but I rather not risk running the engine lean at this time until I get a wide band and make sure the transfer function is correct.

[Dubeckyj]

What's the function for changes in the Closed Loop Bias table? I can increase/decrease by 0.0150, which if lambda, barely changes the AFR. Is the leanest I can go really 14.9 in closed loop?

[SHOZ123]

I wouldn't mess with it. Never did me anything.

[Dubeckyj]

Hey Paul, I came across this thread the other day and I was wondering if you still had the MPH-to-shift values for this: Ford's Cruel Irony

Also, are some spikes normal in data logging, or do I have a noise issue I need to address?

[SHOZ123]

You can't go by the actual value that you put into the table. You just have to pick a number then see if it shifts at the rpm you want it to. If it's too low then raise the mph. I can't remember what the actual numbers were. I ran smaller tires anyway at 225/50/16s.

[Dubeckyj]

Hey Paul, what exactly did you do to tune for secondaries removal? Do you remember if you felt a noticeable difference afterward (the tuning, not the removal). I've had mine out for ever, and while 2k+ is fantastic, light cruise at 1500 seems lacking. If I hit a slight uphill, I have to give it significantly more gas than I think I should & sometimes it'll downshift.

Also battling random misfire; need to change coil packs. But still.

[SHOZ123]

The only thing I did was for the cold start and warm up for the secondary removal.

It sounds like you need to increase the Intake Manifold volume as far as the 1500 rpm issue.