2010 camaro cam surging/bucking

[jmstekguy]

tuning a 2010 camaro ls3 m6, at low speed (1500-2000rpm) im seeing a mild amount of bucking and surging. on hot starts i get a erratic idle as well and the wideband shows rich until it settles (2-3 seconds). The idle on coast down clutch in is also the same, dips down low almost stalling. The car never seems to start crisp when hot, but cold its no problem. The car at any other load drives great and makes great power.

the car has a kaotic (vengence racing cam) .620/.623 lift 235/243 duration and 113 lsa. other mods are litterally just a cold air and longtubes.

when i datalogged on driving the trims fluctuate like crazy and i cant get them under control, when i force it to open loop the car runs great and no bucking or surging at all whatsoever. The i have raised the pe enable higher to cancel it out and raised the dfco enable/disable. any ideas????


thanks

tomto2010camarorev3.hpt

[Tiffo60]

all your idle airflow tables are stock, you can improve the stalling quite a bit with those, hot starts could be your crank timing, try raising it a bit to see what changes. I dont have a lot of experience tuning big cams in the LS motors but on fords most of the driving manners is in the airflow and timing tables.

As far as your fuel trims going crazy when in closed loops thats all maf curve normally.

[jmstekguy]

all your idle airflow tables are stock, you can improve the stalling quite a bit with those, hot starts could be your crank timing, try raising it a bit to see what changes. I dont have a lot of experience tuning big cams in the LS motors but on fords most of the driving manners is in the airflow and timing tables.

As far as your fuel trims going crazy when in closed loops thats all maf curve normally.

Thanks, ill try it out, as for the trims, I forced open loop (just like my ford CMR stuff) and adjust maf curve then turned closed loop on, and still had the problems. i think it was the COTS, as soon as i turned it off the trims evened out as per my open loop tuning, never seen that before and yes the car has cats in it. Maybe they are plugged from the previous tune up (plugs were sooty black when i changed them), even the idle seems good now, just a little 2 second flare up on hot starts...gotta make it perfect.

i just wish there was a little better guide to ve tuning for this, very confusing to say the least.

[Tiffo60]

Thanks, ill try it out, as for the trims, I forced open loop (just like my ford CMR stuff) and adjust maf curve then turned closed loop on, and still had the problems. i think it was the COTS, as soon as i turned it off the trims evened out as per my open loop tuning, never seen that before and yes the car has cats in it. Maybe they are plugged from the previous tune up (plugs were sooty black when i changed them), even the idle seems good now, just a little 2 second flare up on hot starts...gotta make it perfect.

i just wish there was a little better guide to ve tuning for this, very confusing to say the least.

have you used this for the Virtual VE stuff?
http://www.hptuners.com/forum/showth...t-VE-Version-3

[Tiffo60]

Just to add, I know its pricey but I have found Greg Banish's stuff to be well worth the money
http://www.summitracing.com/parts/sme-dvd-2

[jmstekguy]

Just to add, I know its pricey but I have found Greg Banish's stuff to be well worth the money
http://www.summitracing.com/parts/sme-dvd-2

thanks!, i love gregs stuff, i will be buying this one for sure.