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curtbriggs
February 27th, 2005, 12:35 PM
I would like to add my experience to the Idle tips and with thanks to those who on the forum helped me.
My 99 C5, 6 speed with cam change, LT headers had a lumpy 700 to 750 RPM idle. I set the Idle at 910 RPM and was happy until I pushed the clutch in to roll up to a stop. The engine went back to the old rolling Idle.

In Tune, Engine calibrations, Idle,double click on "Desired Idle Speed", there are four columns under Conditions, labeled:
In-Gear A/C on, In-Gear A/C Off. In P/N A/C On, In P/N A/C Off.
I had set the idle speed in the two on the left, set the idle speed in all four columns for the engine operating temperature range. I started at 1000 RPM for a cold engine and went to my desired 910 RPM for normal operating temperatures for my 160* TStat. I would set the normal speed 10-20 RPM high in the two right columns for the manual transmission. This worked for me.

Cheers, Curt

johnsZ06
February 28th, 2005, 01:36 AM
Hmmm, I would think the P/N column is for auto only. I set the idle on my Z06 using the first two columns and it works fine. It dips for a second when I push the clutch in but idles where I set it.

curtbriggs
February 28th, 2005, 02:48 AM
Hmmm, I would think the P/N column is for auto only. I set the idle on my Z06 using the first two columns and it works fine. It dips for a second when I push the clutch in but idles where I set it.

My drive way is 1 1/2 miles long and over a 700' ridge. I usually come down in neutral to creep around bad spots in the gravel road. Until I made the change in the last two columns, I had the original low idle until I came to a stop. Every time I stopped on the way down the Idle would come back to 910 RPM and as soon as I started to roll, it went back to 700-750 RPM.

Curt

SSbaby
February 28th, 2005, 03:17 PM
Good. I'll try that trick tonight...

I can't seem to get my M6 cammed LS1 to idle below 900rpm - I'm not unhappy with it, just curious how low I can get it... it's a lot better than 1050rpm the tuner set it at (even then it wouldn't idle), that's for sure.

bink
February 28th, 2005, 03:43 PM
Hmmm, I would think the P/N column is for auto only. I set the idle on my Z06 using the first two columns and it works fine. It dips for a second when I push the clutch in but idles where I set it.

My drive way is 1 1/2 miles long and over a 700' ridge. I usually come down in neutral to creep around bad spots in the gravel road. Until I made the change in the last two columns, I had the original low idle until I came to a stop. Every time I stopped on the way down the Idle would come back to 910 RPM and as soon as I started to roll, it went back to 700-750 RPM.

Curt
Wow, I didn't realize the P/N tables would help. It's a nifty work-around the "Running Idle Airflow" (RAF) table. The P/N table in an M6 must add some air at non-idle.
You could add a little ( try 0.25-0.50 g/sec? maybe more) airflow at the operating ECT in the RAF table. This would be the conventional method.

curtbriggs
February 28th, 2005, 03:48 PM
Joel, did you get my PM Friday?

Curt


Wow, I didn't realize the P/N tables would help. It's a nifty work-around the "Running Idle Airflow" (RAF) table. The P/N table in an M6 must add some air at non-idle.
You could add a little ( try 0.25-0.50 g/sec? maybe more) airflow at the operating ECT in the RAF table. This would be the conventional method.[/quote]

bink
February 28th, 2005, 03:59 PM
Joel, did you get my PM Friday?

Curt

No. Here?

joel

curtbriggs
February 28th, 2005, 04:04 PM
[quote=curtbriggs]Joel, did you get my PM Friday?

Curt

No. Here?

Yes, I went to your profile and sent two. Must not work.
curtbriggs@direcway.com Try me direct.

Curt

bink
February 28th, 2005, 04:10 PM
[quote=curtbriggs]Joel, did you get my PM Friday?

Curt

No. Here?

Yes, I went to your profile and sent two. Must not work.
curtbriggs@direcway.com Try me direct.

Curt

I just tested it. Working now. :D
Was it down Friday?

joel