Idle RPM increase

[fastd]

New to HP Tuners.

I have a stock 2001 LS1 from a Corvette.

If I want to increase my in-gear idle speed from 550-600 to 650-700 rpm, would I be able to just change the Base in-gear target (assuming Park/Neutral is above in-gear - if not, I would bump that up to be 50-100 rpm over in-gear)? Or do I need to change other settings/inputs?

My goal is to get my alternator to spin faster when sitting at a stop light - right now rpms are somewhere between 550-600 and that's not enough alternator rpms to keep voltage above 12.5 at a stop light.

Thanks.

[blindsquirrel]

It shouldn't do that. Why not find out what's wrong with the charging system?

[fastd]

Based on my pulley size and damper size and idle rpm, at 550 rpm, my alternator is only spinning at 2,100 rpms. My pulley size 1.95" and Powermaster doesn't make a smaller pulley and doesn't recommend going smaller than that anyway.
I've been told by Powermaster that the alternator needs to spin at a minimum of 2,400 to achieve the advertised minimum "at idle" voltage; my alternator is rated at 105 amps at idle, 150 at cruise, and 169 at top end. At rpms in the 800-2000 range, my system voltage is about 13.5.

If I increase my in-gear idle from 550 rpm to 650 rpm, it should spin the alternator at 2,493 and give me enough alternator output at idle.

Based on that, there may not be anything wrong with my charging system...but I am open to the possibility that there is something wrong with it.

If my system is working OK, increasing the idle speed may be a quick fix to increase the voltage at idle (I have my MPVI3 on order).

Just interested to know what settings (beside the base in-gear setting) I need to change to increase the in-gear idle speed from 550 to 650.

Thanks.

[blindsquirrel]

Oh. "2001 LS1 from a Corvette", as in 'not actually a 2001 Corvette using all the 2001 Corvette parts'.

[SiriusC1024]

New to HP Tuners.

I have a stock 2001 LS1 from a Corvette.

If I want to increase my in-gear idle speed from 550-600 to 650-700 rpm, would I be able to just change the Base in-gear target (assuming Park/Neutral is above in-gear - if not, I would bump that up to be 50-100 rpm over in-gear)? Or do I need to change other settings/inputs?

My goal is to get my alternator to spin faster when sitting at a stop light - right now rpms are somewhere between 550-600 and that's not enough alternator rpms to keep voltage above 12.5 at a stop light.

Thanks.

Yeah that's all you have to do. I hate the low idles and variable pressure oil pumps in newer vehicles. Below 700 no thanks. It's trading emissions for wear.

Also, and you probably know already, alt voltage should be 14.1V for battery life. Some ecu's have a voltage table that varies with temperature for this reason. That'll be found under the System tab.

[fastd]

Yeah that's all you have to do. I hate the low idles and variable pressure oil pumps in newer vehicles. Below 700 no thanks. It's trading emissions for wear.

Also, and you probably know already, alt voltage should be 14.1V for battery life. Some ecu's have a voltage table that varies with temperature for this reason. That'll be found under the System tab.

Great; thank you Sirius.
I didn't realize the low idle was driven by emissions.

What do you recommend targeting for idle in Park & Neutral and idle "in-gear"?

[Alvin]

I run into this all the time for swaps. The stock idle speed is often too low for aftermarket alternators and powersteering pumps ETC.

[SiriusC1024]

800 should be sufficient. That's base for the Corvette.

[fastd]

I changed the base idle settings - from 625 to 725 (neutral and park) and from 550 to 675 (in gear); no problems changing the settings at all; voltage is now much improved in gear at stop light; thanks for your help.