PDA

View Full Version : fueling Questions on T-SMEC



1BADVAN
10-01-2010, 12:15 PM
I was looking at trying to use the AFR lines to adjust fuel and i only see 3 that have the live show up. full and part throttle fuel and fuel baseline from map. What does the fuel baseline one do?? I know on some cals there is a Fuel no throttle table but i don't see one here, how can i adjust fuel at idle/ coasting down?

ShelGame
10-01-2010, 01:19 PM
Fuel baseline and fuel no throttle are the same thing. There's a fuel flow chart posted in the EFI section that will walk you thru how the main fuel tables are calculated and used.

The AFR line only shows up on those 3 tables because those are the only 3 tables that have the AFR built into it.

If you want to adjust the idle fuel, there are a few ways to do it.

1) Reduce the PumpEff at low RPM. For some reason, Chrysler left the PumpEff at like 60+% even at idle. When, in reality, this is probably not very realistic. So, reduce the PumpEff in maybe 5% increments below 1200rpm and see if that helps.

2) Reduce the baseline/no throttle fuel table near idle vacuum. If you have a different cam or cam timing than stock, it's likely that you're operating in a different part of this table than stock and are calculating a richer mixture.

3) Spark scatter fuel - Chrysler actually uses spark scatter and subtle fuel changes to control the idle speed primarily. The AIS motor is actually a last resort. This is because fuel and spark changes are much more responsive than the AIS motor. But, the constant changing spark and fuel make it hard to tune. There's another thread here about turning them off for tuning purposes.

4) Then, there is the adaptive fuel which also works at idle. You might need to adjust those kick values. You can also dis-able the adaptives for tuning purposes...

1BADVAN
10-01-2010, 02:55 PM
thanks!

turbovanmanČ
10-02-2010, 02:38 AM
Good info Rob. :hail:

Juggy
10-03-2010, 10:10 PM
can u link to the flow fuel chart? i cant find it

with the pumping efficiency

if the car is too lean at idle , do i need 2 lower it??? having problems keeping the car running with the cal i have. i copied the fuel start up that was on the S60 cal and i was finally able to fire up and stay running, but as the car heated up it seemed like it slowly leaned out until the point it stalled itself out unless i stayed on the gas.

just curious about this pump eff. its alot higher then the S60 cal right now so i am figuring i need to lower it to keep the car running? got 72pph injectors and a taft S3 cam

ShelGame
10-03-2010, 11:29 PM
The S60 cal used a very modified PumpEff table to scale for injectors. The values in that table do not compare at all to real-world pumping efficiencies. The fuel tables are basically stock T2 fuel tables. It's really kind of a hack way of doing a big-injector cal, but that's what they did. Driveability was obviously not a priority. You certainly should NOT copy individual tables out of that cal into a 'modern' cal. I included it in the templates mostly for reference. And, I know a lot of people still have good luck using it.

Spark timing should be good to copy over, though.

turbovanmanČ
10-11-2010, 06:25 PM
Spark timing should be good to copy over, though.

Just becareful, its very aggressive and without race gas, it will knock.

Juggy
10-13-2010, 05:45 PM
simon no knock with S60 cal n crappy old fuel 94 octane
i even ran a more aggressive cal with no knock.....my 2.5 likes timing :eyebrows:

turbovanmanČ
10-13-2010, 05:47 PM
simon no knock with S60 cal n crappy old fuel 94 octane
i even ran a more aggressive cal with no knock.....my 2.5 likes timing :eyebrows:

I ran the S60 on my old engine, rattled without race fuel.

My old engine loved timing too, then it blew up, :eyebrows: