Closed Loop Idle
Discussion
For anyone with an aftermarket ECU I can highly recommend going closed loop idle control.
Many thanks to Nathan at Lloyd Specialists Developments for adding this new strategy to my extensive list of recent improvements to 'Ol Gasbag'... and without me even asking for it.
The name being somewhat misleading as the idle benefits of closed loop idle are really just a small part of what it offers, the biggest benefit to my mind is how this strategy further smooths out sub 2,000rpm driving and gear changes.
Today I was playing about to see just how flexible the low speed manners of 'Ol Gasbag' have become with CLI and it's almost laughable.
Trickling through town in 3rd at 20mph I found myself up-shifting to 4th then to 5th and holding a super smooth 33mph in top at 1,100rpm without a hint of stutter or shunt.
Balancing the engine on and off throttle at super low revs becomes such an intuitive, natural and civilized way to drive... a few times I even found myself forgetting I was in the TVR.
Clearly closed loop idle doesn't add any power or outright performance so it's not one of the exciting things we all like to talk about, but from what I can tell it has made the single biggest improvement to engine flexibility & drivability on 'Ol Gasbag'
Highly recommended
Many thanks to Nathan at Lloyd Specialists Developments for adding this new strategy to my extensive list of recent improvements to 'Ol Gasbag'... and without me even asking for it.
The name being somewhat misleading as the idle benefits of closed loop idle are really just a small part of what it offers, the biggest benefit to my mind is how this strategy further smooths out sub 2,000rpm driving and gear changes.
Today I was playing about to see just how flexible the low speed manners of 'Ol Gasbag' have become with CLI and it's almost laughable.
Trickling through town in 3rd at 20mph I found myself up-shifting to 4th then to 5th and holding a super smooth 33mph in top at 1,100rpm without a hint of stutter or shunt.
Balancing the engine on and off throttle at super low revs becomes such an intuitive, natural and civilized way to drive... a few times I even found myself forgetting I was in the TVR.
Clearly closed loop idle doesn't add any power or outright performance so it's not one of the exciting things we all like to talk about, but from what I can tell it has made the single biggest improvement to engine flexibility & drivability on 'Ol Gasbag'
Highly recommended
It does take a bit of playing with to get right - remember if you're trickling around at 1,100 rpm then you *SHOULDN'T* be on the closed loop idle settings but yes, I got mine holding a nice steady 800 rpm with a little hunting and 850 rpm on idle with pretty much unnoticeable hunting...
Phil
Phil
ChimpOnGas said:
For anyone with an aftermarket ECU I can highly recommend going closed loop idle control.
Many thanks to Nathan at Lloyd Specialists Developments for adding this new strategy to my extensive list of recent improvements to 'Ol Gasbag'... and without me even asking for it.
The name being somewhat misleading as the idle benefits of closed loop idle are really just a small part of what it offers, the biggest benefit to my mind is how this strategy further smooths out sub 2,000rpm driving and gear changes.
Today I was playing about to see just how flexible the low speed manners of 'Ol Gasbag' have become with CLI and it's almost laughable.
Trickling through town in 3rd at 20mph I found myself up-shifting to 4th then to 5th and holding a super smooth 33mph in top at 1,100rpm without a hint of stutter or shunt.
Balancing the engine on and off throttle at super low revs becomes such an intuitive, natural and civilized way to drive... a few times I even found myself forgetting I was in the TVR.
Clearly closed loop idle doesn't add any power or outright performance so it's not one of the exciting things we all like to talk about, but from what I can tell it has made the single biggest improvement to engine flexibility & drivability on 'Ol Gasbag'
Highly recommended
I thought closed loop came in a little higher than idle and turned off at 3 to 4k .. I can`t see how lambda feed back would be quick enough after that .Many thanks to Nathan at Lloyd Specialists Developments for adding this new strategy to my extensive list of recent improvements to 'Ol Gasbag'... and without me even asking for it.
The name being somewhat misleading as the idle benefits of closed loop idle are really just a small part of what it offers, the biggest benefit to my mind is how this strategy further smooths out sub 2,000rpm driving and gear changes.
Today I was playing about to see just how flexible the low speed manners of 'Ol Gasbag' have become with CLI and it's almost laughable.
Trickling through town in 3rd at 20mph I found myself up-shifting to 4th then to 5th and holding a super smooth 33mph in top at 1,100rpm without a hint of stutter or shunt.
Balancing the engine on and off throttle at super low revs becomes such an intuitive, natural and civilized way to drive... a few times I even found myself forgetting I was in the TVR.
Clearly closed loop idle doesn't add any power or outright performance so it's not one of the exciting things we all like to talk about, but from what I can tell it has made the single biggest improvement to engine flexibility & drivability on 'Ol Gasbag'
Highly recommended
What did interest me when one of the guys from Lloyds said he combined TPS and map together ,rather than one or the other .I always thought gave quicker response but you loose a few mpg .
My idles about 850rpm with an AFR of around 14.6 ,its smooth enough .
Bassfiend229hp said:
It does take a bit of playing with to get right - remember if you're trickling around at 1,100 rpm then you *SHOULDN'T* be on the closed loop idle settings but yes, I got mine holding a nice steady 800 rpm with a little hunting and 850 rpm on idle with pretty much unnoticeable hunting...
Phil
With respect Phil, that's not strictly correct, well not in my case anyway.Phil
Firstly lets understand the rules I'm running....
- Enable idle control under 1400 RPM
- Enable idle control when throttle under 2%
- Target idle speed 1050 RPM
- Fast target idle speed 1100 RMP
- Idle target delay rate 0.50
When trickling through traffic at low RPMs what you'll find is you're on and off throttle way more than you realise, so you're effectively transitioning from above the 2% throttle to below it all the time.
And an awful lot of this goes on under the 1400 RPM my CLI is configured to come into play.
So below 1400RPM when I come off the throttle the delay rate of 0.50 ensures my rpms will hang very slightly, in practice you don't really notice the hang at all but it bridges the violent peak & trough of on/off throttling or a gear changing beautifully.
So you see CLI is not really/only about idle at all, and personally I wouldn't be looking for 800/850 rpm idle with my Stealth cam, a 1050rpm target is absolute perfection in my case.
The truth is the best trick CLI has is smoothing out the transition from on/off throttle at at low rpms, IE gear changes and just trickling through traffic at very low speeds where you ideally go from a feather light touch of the throttle to zero throttle coasting then back to a whiff of throttle again.
In every other Chimaera I've driven you tend to be forced to maintain a certain (slightly higher than desirable) engine speed to ensure smooth progress and gear changes, typically that also equates to one lower gear than a big old V8 that's only pushing along just over 1000kg should be in.
So what I've found with my CLI is there's no more coming off the throttle & falling in a hole in that split second as you swap cogs, lower RPM gear changes are therefore seamlessly bridged like you're the most skilled rev matching driver ever. Any trace of shunt is completely blended out and on/off throttle pulsing through town in a higher gear becomes the relaxed norm, this and the slicker gear changes combine beautifully to deliver an insanely smooth drive.
Another case of a super fast computer beating the human, what the Canems system is doing on closed loop idle is so fast and so smart I'm confident even the best driver couldn't mimic it using the throttle pedal alone.
And the best bit is it's all done for you automatically by the ECU and so well you don't even think about it, all you experience is a way way smoother drive
Very impressive and highly recommended, thanks Nathan..
SILICONEKID345HP said:
I thought closed loop came in a little higher than idle and turned off at 3 to 4k .. I can`t see how lambda feed back would be quick enough after that .
What did interest me when one of the guys from Lloyds said he combined TPS and map together ,rather than one or the other .I always thought gave quicker response but you loose a few mpg .
My idles about 850rpm with an AFR of around 14.6 ,its smooth enough .
Daz, it seems you're getting closed loop fueling (with AFR targets), all mixed up with closed loop idle control.What did interest me when one of the guys from Lloyds said he combined TPS and map together ,rather than one or the other .I always thought gave quicker response but you loose a few mpg .
My idles about 850rpm with an AFR of around 14.6 ,its smooth enough .
They are two very different things mate
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