Hello Carb guys,
Quick? I have a 350 with a Holley DP and when I start the motor in the morning to warn it up it idles at 25K until I can tap on the gas pedal about 3 minutes later. Is this good or bad and if it is bad what do I need to do to fix it?

 

sounds like the high idle adjustment is a little too high. there is a red screw under the choke which can be turned slightly too lower the idle. otherwise this is normal and if you live in a cold temperature probably needed, although 1800 RPM would be better probably.

 

Thank you xpndbl3 ,
Will this cause engine damage if I can't adjust the idle speed soon?

 

25K As in 25,000 RPM Isn't that what a Jet engine turns!

You need to adjust your fast idle speed screw. It is fairly simple to do.

 

I thought it should idle at 5k and it does after I tap the gas pedal after 3 minutes of warm up. I live 7000 feet above sea level and it is very cold so I was wondering if an idle this high on cold startup will damage my motor?

 

Edited because I posted incorrect information.

 

The highest step on the fast idle cam should be adjusted to give an idle of about 1,600-1,700 in Park/Neutral.

Will it hurt anything? Probably not. Will it waste gas? Yes Will it cause you to have to stand on the brake when it is cold? Yes.

You are meaning 2.5K or 2,500 RPM. 25K is 25,000 RPM, formula one cars might hit 20,000 rpm with 15,000 being on par. Idle should be around 550-600 RPM when fully warmed up.

 

Personally, I'm not really "warm and cozy" about an engine running at even 1,800 RPM when it is dead cold. Then again, it may be the express ticket to getting that shiney new V-8 that you've been thinking about.

The high idle setting is supposed to be adjusted with the engine at full operating temperature - just like almost every other adjustment. Setting the high idle cam RPM at 1,500-1,800 with the engine fully warmed is more likely to produce about 1,000-1,200 RPM when a cold engine is first started. That's just what the factory intended. If it is actually running at 1,500-1,800 RPM when first started, your idle cam adjustment screw has been randomly and improperly adjusted, and the proper procedure needs to be applied. Or, you can start saving for that new engine.

Further, don't place too much confidence in the RPM indication of the factory tachometer. Use a diagnostic tach to set the adjustments to the proper specs.

 

fast idle should be around 12-1500 cold, and will go a bit higher once warmed up a bit.