[STYLO LT1]

So if memory serves me right, I remember my manual 2016 SS idling at 500 RPMs with the stock throttle body. I recently installed a ported and polished throttle body with no increase in size. Now the car idles at 600 RPMs even after doing the relearn procedure. There are no leaks detected and car has not thrown any codes. Will it be okay to be in a slightly higher RPM at idle? I appreciate your input.

[BrianL]

My Mamo V2 PTB still idles at the same RPM after the relearn process.

[ctrlz]

Below is from the repair manual. It is in table form and lists hundreds of parameters. I quoted the column headers and the idle parameters:

SPECIFICATIONS > K20 ENGINE CONTROL MODULE: SCAN TOOL INFORMATION

Engine Control Module Scan Tool Data

1) Parameter; 2) System State; 3) Expected Value; 4) Description

1) Desired Idle Speed;

2) Engine Idling;

3) Approximately 650 RPM;

4) This parameter displays the
desired engine idle speed as
commanded by the control
module. The desired idle speed
varies depending on engine

load.

[STYLO LT1]

Thanks guys. The only thing I can think of is that the butterfly isn't seating correctly. Either way, the idle is just slightly off. Will it be okay living in that range at idle? Should I just send it back?

[Heat Magnet]

I don't think a 100 RPM increase in idle should be something to worry about. I remember when my dad had his 1980 Corvette fixed up for some mechanical issue, they actually increased the idle slightly since it was pretty rough at the RPM it was at. Just remember, VTEC motors idle at 8,000 RPM so 500 to 600 RPM is nothing.

[Crushin_LT1]

Originally Posted by Heat Magnet

I don't think a 100 RPM increase in idle should be something to worry about. I remember when my dad had his 1980 Corvette fixed up for some mechanical issue, they actually increased the idle slightly since it was pretty rough at the RPM it was at. Just remember, VTEC motors idle at 8,000 RPM so 500 to 600 RPM is nothing.

Idk I came from a K24 and it idled at around 850 or so, not 8000 lol

[m6-lt1]

500 rpm sounds kind of low for it to idle at that. I feel like something wasn’t seated properly before the Tb install and during the install you seated it properly and now it’s idling where it should.

[Crushin_LT1]

My 2021 M6 idles at 650, I understand the autos idles around 800?

[Spaceme1117]

Ported throttle body won't seal quite as well as a stock TB and this is likely the cause of the increased idle.

You would likely need a tune to get the idle back to normal.

[STEVE41]

Originally Posted by Spaceme1117

Ported throttle body won't seal quite as well as a stock TB and this is likely the cause of the increased idle.

You would likely need a tune to get the idle back to normal.

a tune can't fix it if too much material is removed around the throttle blade area.

[BDPhoto519]

Idle speed changes based on a few conditions... But fully warmed up, at operating temperture and normal-ish outside temperture your target idle for an Auto LT1 is 575 RPM.