lowering idle with cam

[bob442]

So for all that dont know off hand i have long tube headers, a strip performance cam shaft from wottech:

http://wot-tech.com/shop/gm-60v6/strip-performance-camshaft/prod_243.html

11.5:1 CR pistons, 65mm tb, and a straight through exhaust, all in a 3400 of course.

Anyways i have had my base tune loaded onto my car, and it idles, drives runs great once it has warmed up and is out of open loop, it doesnt lean out or run rich, it just has alot of timing pulled and lower RPMs are kind of a dog for right now, so my question is this, with 111 LSA idling at 870-925 RPM i barly hear any lobe, should i get the idle dropped down more so i can have that wonderful stress relieving, heart racing lobe noise when i'm at idle or will this throw street-ability right out the window? or is there a happy medium? i'd love to be able to stop watching 953400modified's video of "got lobe" and have my own

[SappySE107]

set it to 700 and tell me how it sounds.

[Superdave]

You can play around with the idle advance as well but you have less than 50 degrees of overlap so it's not really going to lope like some of the others.

[SappySE107]

for sure, and set the open loop stuff on the rich side if you want it to just sound absurd for a V6.

[Superdave]

Here is a little over 70 degrees of overlap, stock compression with longtubes and TD's.. 1K RPM idle http://www.youtube.com/watch?v=XP048yTMb_8

[bob442]

Well should I just be happy with how it sounds at 700rpm closed loop? My tuner was concerned with the placement of my o2, so he put the open loop run time longer and raised the idle in hopes for the o2 to get hotter and get better readings. My o2 is at the end of the cone of my collector, about as high up as I can get it, and I used a weld on bung an had done the best I could go flatten out the pipe around the bung so it would get a good reading. The o my thing I'm goin to be able to do it cut off the little washer on the o2 to drop it down another 1/8"....

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[robertisaar]

for sure, and set the open loop stuff on the rich side if you want it to just sound absurd for a V6.

i noticed this when i was testing my single-fire code, commanded AFR was something like 6:1... an otherwise stock LH0 sounded like a couple of shotguns under the hood for the 2 seconds it took me to realize that something wasn't quite right.

obviously, don't go that nuts.

+1 on the add SA at idle.

[bob442]

Please don't use abbreviations on tuning terms with me lol when there's over a 1000 parameters I can't keep up


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[Superdave]

Are you using a heated o2 sensor?

[bob442]

Stock one so yes


Sent from my iPhone using my iPhone at work cuz I have nothing to do

[Superdave]

then there would be no reason to lengthen the open loop times.. The o2 relies on it's own heat, not the exhaust system heat like the old 1 wire sensors.


I found that 60 sec cold, 30 sec warm and 10 sec hot works well with the 4 wire sensors.

[bob442]

now maybe one of you guys have an answer for this, after the tune, and with the new injectors, keep in mind nothing is sorted out here yet, my tuner just built up a tune, loaded it, we went for a quick ride and that was it for now till i get dyno time funds, when the car is cold (open loop, high idle) if i put it into gear, it will surge till it dies, when its warmed up(closed loop), the problem is gone, how ever when driving, and random throttle open and close (driving or not) the RPM's will drop right down and pick up, they will go as low as 400-500 rpm and almost die. seems to happen more when in gear, i dont think its the torque converter not releasing...but any ideas?

[SappySE107]

what kind of a tune is that? What you described is a single attempt at the baseline, not something I would take to a dyno. If it has issues, it isn't ready for a dyno and still needs to be tuned.

[bob442]

the base tune was ment for it to run properly with the larger injectors, compensate for mods, and have no knock.

[dskopek]

Here is a idle with a turbo and a 224/230 duration at .050 lift. Sorry the sound is not real good but you get the idea.

http://youtu.be/K4CCV1U2Ojc