View Full Version : This might be a tuning issue or something else.


vilkata
07-01-2005, 01:33 AM
Sorry if this is in the wrong forum but I figured I would start here. Recently I had heads/cam done to my car. To be more specific refer to my signature for the modifications. The only modification that wasn't done at this time was the true dual exhaust. That was installed a couple of months earlier. What I have questions on is the fact that my rwtq just seems low. I'm not sure what modification to do next or something to look into fixing to bring the torque curve/max to a higher amount. I'm not sure if I need to supply more information. I'm still fairly new to all of this. If there is, I can ask the shop that did the build for more/different specs. Also, he found that my rear gears are 3:42. I was under the impression that the A4 cars came with a 3:23 rear gear stock. I did buy this car used so perhaps the previous owner had changed the gearing. Also, if this is in the wrong category I apologize.

jimmyblue
07-01-2005, 10:15 AM
Sorry if this is in the wrong forum but I figured I would start here. Recently I had heads/cam done to my car. To be more specific refer to my signature for the modifications. The only modification that wasn't done at this time was the true dual exhaust. That was installed a couple of months earlier. What I have questions on is the fact that my rwtq just seems low. I'm not sure what modification to do next or something to look into fixing to bring the torque curve/max to a higher amount. I'm not sure if I need to supply more information. I'm still fairly new to all of this. If there is, I can ask the shop that did the build for more/different specs. Also, he found that my rear gears are 3:42. I was under the impression that the A4 cars came with a 3:23 rear gear stock. I did buy this car used so perhaps the previous owner had changed the gearing. Also, if this is in the wrong category I apologize.

Looks like your power is coming from RPM rather than
torque build-out, true.

Maximizing torque for a set engine configuration is
just fuel & spark. You might want to have a dyno
curve in front of you with the wideband info. Torque
responds to more spark and fatter mixture in the
midband; at the top end fat mixture will steal from
HP when the burn time gets longer than power stroke
time. Some folks run like 12.5:1 (NA) in the middle
fading to 13:1 up top. Then you tweak the spark up
to what she'll take without pinging.

Look at what the wideband says your fueling is,
relative to that. This (followed by the spark tweak)
is your best as-is hope for torque improvement.

The 2800RPM converter - any locked/unlocked
RWT/RWHP comparison? Is it inefficient and maybe
stealing some?

Have to keep an eye on the dyno operator and the
vehicle data. Seems like a lot of dynos spit out very
"processed" results, needing vehicle-specific data
(garbage in, garbage out). If you told it the wrong
tire size, gears, etc. that might (or not) bend the
reported results. You might look in the dyno section
for ideas about that, especially whether or not the
dyno in question might make an erroneous correction
based on erroneous gearing entry.

vilkata
07-02-2005, 01:24 AM
Thanks for the reply. There is a lot more to this than what it might seem on the top. I do know that it was unusually hot out the day that the dyno session took place. I'm not sure about the locked/unlocked aspect of the converter however. Right now I'm pretty happy with how the car runs. But there is always room for improvement. So I'm doing a little research to see if this is a sign of anything mechanically wrong with the car. I haven't done anything to the ignition system yet as far as parts go. So perhaps that is where I need to make the modifications next. Who knows, I guess that its only money and you can't take it with you. So let the next modification session begin!