Cars Idle too Low?

[dhandeh]

Pretty much most everyday standard (petrol) cars, which have not been tuned etc, should idle around 700 - 900 rpm. Diesel cars, will idle around 550 - 800 rpm on average. Larger diesel engines will idle around 500 rpm.

Now, tuned/ performance engines will have to idle higher, due to the camshafts (affecting cam timing) that more than likely would have been fitted, the lightened flywheel (purpose of the flywheel, is to keep the engine rotating between the non power strokes) etc. You fit a lightened flywheel to a standard car, and don't change the idle speed, it will be erratic at idle. You would have to bring up the idle speed, to create less time between each cylinder firing.
F1 engines, have no flywheel to speak off, hence why they idle at 5,000 rpm.

In a nutshell, the more performance the engine the higher the idle speed.

 

[GT'S BiG FaN]

My GMC suburban idle's at 600 RPM (in real life)

 

[shirakawaa]

I find that most racecars in the game have a too low idle.
Most roadcars seem ok... but I don't think it's realistic to still have a ~750 rpm idle on a fully tuned engine.

 

[ParkourVeyron]

Pretty much most everyday standard (petrol) cars, which have not been tuned etc, should idle around 700 - 900 rpm. Diesel cars, will idle around 550 - 800 rpm on average. Larger diesel engines will idle around 500 rpm.

Now, tuned/ performance engines will have to idle higher, due to the camshafts (affecting cam timing) that more than likely would have been fitted, the lightened flywheel (purpose of the flywheel, is to keep the engine rotating between the non power strokes) etc. You fit a lightened flywheel to a standard car, and don't change the idle speed, it will be erratic at idle. You would have to bring up the idle speed, to create less time between each cylinder firing.
F1 engines, have no flywheel to speak off, hence why they idle at 5,000 rpm.

In a nutshell, the more performance the engine the higher the idle speed.

Exactly. The purpose of a lighter flywheel is to quicken engine response, so higher performance cars need to idle higher. But I've never heard of a non-tuned road car idling at 1500 RPM, unless you're trying to power a football stadium.

 

[MasterFocus]

I find that most racecars in the game have a too low idle.
Most roadcars seem ok... but I don't think it's realistic to still have a ~750 rpm idle on a fully tuned engine.

Well my friend has a 420whp '06 STi and it idle @ about 650/700rpm

 

[shirakawaa]

Well my friend has a 420whp '06 STi and it idle @ about 650/700rpm

With wild cams that would be too low. Also, in general the idle on tuned cars (not only the sound, but actual rpm) is excessively stable in GT.

 

[savage388]

More modern cars with port fuel injection are able to keep an engine running at much lower rpm thanks to far superior timing and fuel control. Even without variable valve timing like vtec the they run much much smoother across the rpm range. There's just no comparison to old carbed monsters.

 

[hossdeluxe]

The 787B has a idle that jumps up and down from 0-900 because of the big rotatory engine it has, the tact just stays at 1500 in game but the sound is fairly close to true. Also a interesting fact is that engines idle was usedjust solely to kept the engine warm, thus the epic WOOP WOOP WOOP sound it makes.

 

[shirakawaa]

That is only an audio effect though, rpm don't actually jump around in GT5 due to irregularities in power delivery (although it may look so when driving with very hard suspension settings) but remain constant and smooth.

 

[niky]

My cammed car idles at 750 rpm. It idles pretty badly when cold, but it idles.

 

[crossup]

You're right that I was really talking race motors used on the street. Very sad about the lack of lope as you note....also sad that we cant choose cams in the game but thats probably 5.5million features down the popularity list
and F1...where do we start? WOT during decel to increase downforce by using exhaust to augment air flow at lower speeds..running on less than 8 holes..on purpose and so forth

Since your getting into real world modifications, if a motor has enough cam in it that it idles at 2 grand then it's hardly a street motor. You may drive it on the street but it's more at home on the track. Race cars don't count as they are not intended to idle for any length of time. In fact just a couple of years ago the only f1 teams that could idle there cars when at temp were Ferrari and mclaren. As far as older motors racy motors go the idles were very lopey and rough so the rpm wouldn't really stay constant anyway, and gt5 definitely doesn't reflect any of that.

 

[savage388]

You're right that I was really talking race motors used on the street. Very sad about the lack of lope as you note....also sad that we cant choose cams in the game but thats probably 5.5million features down the popularity list
and F1...where do we start? WOT during decel to increase downforce by using exhaust to augment air flow at lower speeds..running on less than 8 holes..on purpose and so forth

I was talking about a couple of years ago... When f1 was much simpler to understand today the ecu mapping, valve timing, ect must be so complex to do that while still achieving engine braking I doubt anyone but them completely get it.

 

[Energizerrr]

Idle at 1500? There's something wrong. 👍
Normally cars idle at around 700/1000rpm, 500 seems low but ok.

 

[Cjm845]

Some high octane cars due have to idle a little higher than standard but only ones I can think that would ever idle over 1000 would be maybe tuned rotary or Vettel, f1's. Would be good if you could alter it in game lol

 

[daan]

Mine idles at 2400 for a few seconds directly after start up, then drops to 1700 and then, as it gets warmer, it gradually works its way down to a warm idle of about 800.

A cold engine will always idle higher than a warm one.

 

[ECGadget]

I know all the cars I've been in idle between 650 and 900.... unless the choke is engaged, then it's 1200 rpm

 

[ghd765]

Most of my GT5 cars idle around 800rpm (occasionally up to 1100), as most do in real life here in the UK. It could be different in the US, due to the lower octane petrol.

 

[YankeeRanger]

in real life my civic idles @700 and stalls around 200.............