arghx

iTrader: (3)

Those of you who tune on loading dynos, what types of settings and tuning processes are you using? I've used a Dynojet 444xl and a Land & Sea Dynomite with a dyno operator actually adjusting settings for me.

I've tried the hold RPM thing. It helps for getting cruising rpms dialed in for example. It doesn't seem to take long for the EGT's to start climbing and all the hotside piping gets really hot. So I can't do that for too long.

I'm also trying to get a feel for the fixed load % settings. The one time I used the loading feature on the Dynojet I tried 10% load. That sounds pretty low and it didn't seem to affect things that much compared to running on inertia only.

On this Land & Sea dyno I've been running at 30% load. The first thing I've noticed at the car drives much more "naturally." When I let the clutch out from a dead stop it doesn't have that weird feeling of no feedback through the gas pedal that you get when you are on inertia only. I found that sustained driving at highway cruising speeds starts to heat up the EGT's again, so I have to keep an eye on the gauge and have cooling-off periods. WOT 3rd gear runs at 30% load seem to be a little bit different (AFR and load cells change a bit) than running on inertia, but nothing drastic.

So my questions are:

1) What are some good ways for me to efficiently utilize the loading for driveability tuning? The main concern is finding stumbles or rich/lean spots in vacuum or low part throttle boost. This reduces the amount of hardcore tedious road tuning.

2) Just how useful can the "hold rpm" feature be? It helped me a little bit with settings cruising AFR's at 3000rpm for example. But with the EGT's heating up I wasn't comfortable using it for me than a couple minutes at a time.

3) What % load is a good ballpark # to approximate typical street driving? I want to get a lot of good 'realistic' tuning done on the dyno so that the street tuning doesn't take too long (meaning less risk of accidents or tickets).