SCT Tuning

[SHOZ123]

What benefit do you think you will get from going to plastic? It gets just as hot as the aluminum one does. The plastic one is set up for the +98 PCMs which have a faster processor and this throws the whole table out of whack with you '97 PCM tables.

I tried it once and it ran so lean I didn't even want to try. It's one thing to do minor changes in part of the MAF table but to completely modify the entire table takes a lot of time and tune modifications.

 

[Dubeckyj]

Bummer. Ok, aluminum it is. It just looks like the plastic would cause less of a restriction at WOT.

 

[Dubeckyj]

So I dialed in the lower region of my MAF this morning. Considering how un-stock the intake is, it wasn't off by much. At the beginning, it was off by 5% at idle, and down to 1.5% at 286 counts, and 1's above that (maybe I hit open loop not-learning mode?).

Now Idle's fluctuating around 1% error (but the banks are 5% either way, problem?) and most error beyond that is 2%. I remember reading that factory is 5% error, so I'm not going to chase 0%.

New question, how bad is it that my banks are 10% different at idle?

 

[illSHOyou]

So I dialed in the lower region of my MAF this morning. Considering how un-stock the intake is, it wasn't off by much. At the beginning, it was off by 5% at idle, and down to 1.5% at 286 counts, and 1's above that (maybe I hit open loop not-learning mode?).

Now Idle's fluctuating around 1% error (but the banks are 5% either way, problem?) and most error beyond that is 2%. I remember reading that factory is 5% error, so I'm not going to chase 0%.

New question, how bad is it that my banks are 10% different at idle?

Can I see some screen shots of base spark table and MBT spark table, and maybe a few other modifier tables. I have no stock table information available to me. It would be very benefical to see some tables so I can get a idea whats left on the table in the stock program. I feel the stock modifiers have convinced me that this car has dual personalities like Dr Jekyll and Mr Hyde. Sometimes WOT are amazing and others lacking....

I believe the stock program is soft on the timing on the bottom end, obviouslly runs pig rich on the top end, and not sure if timing disapears at redline....

Be interesting to know...

 

[SHOZ123]

Here's the base timing table.



here's the MBT table

 

[Dubeckyj]

I finally have AWL1. Holy ball-sack, there's a ton more options. It'll take a while to learn what everything else does, but I'm searching for the 3.98 final drive lockup in 4th issue fix. So far, I see a gear ratio menu where there's a chain ratio box. This seems like the culprit to me, but it says 1.0857, and I have no idea where that number comes from. Do I multiply or divide it by 1.056 (3.98/3.77)?

Edit: after looking at Paul's ratio post on tcca, I figured out it's a ratio of the teeth. 3.77 final drive is 35 & 38; 38/35=1.0857. So I put in 39/34, or 1.1471. I'll be testing it out on the way to work tomorrow, so we'll see if that was the tweak.

 

[illSHOyou]

I finally have AWL1. Holy ball-sack, there's a ton more options. It'll take a while to learn what everything else does, but I'm searching for the 3.98 final drive lockup in 4th issue fix. So far, I see a gear ratio menu where there's a chain ratio box. This seems like the culprit to me, but it says 1.0857, and I have no idea where that number comes from. Do I multiply or divide it by 1.056 (3.98/3.77)?

Edit: after looking at Paul's ratio post on tcca, I figured out it's a ratio of the teeth. 3.77 final drive is 35 & 38; 38/35=1.0857. So I put in 39/34, or 1.1471. I'll be testing it out on the way to work tomorrow, so we'll see if that was the tweak.

Talk to Paul, he should have the fix for that one as he ran a set of 3.98.


Have you been paying attention to engine timing and ECT data logging? I made some good pulls earlier today with engine temps around 190 degree F. Looks like the PCM was calling for max timing the whole way and car felt strong. However a later pull starting out at engine temps of 200 degree F and lots of timing flux by the PCM. Looks like I was riding the knock sensor through the pull.

I am thinking a change in thermostat temp might be in order.

 

[SHOZ123]

Not thermostat temp but fan turn on temp.

 

[illSHOyou]

Not thermostat temp but fan turn on temp.

Paul, what is the factory open point on the stock thermostat? I can't find specs on the internet.

I data logged the turn on temp is 206 degree F with the current program. I would imagine the factory turn on temp be much higher?

 

[SHOZ123]

The t-stat is rated at 180F to start to open. I always set the low speed fan to come on at 202F and hi speed on at 210F. Factory is around 215F for low speed fan turn on.

 

[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]

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]

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.