LS with cablethrottlebody

[flyingdutchie]

I have the LS 6 litre with the LS3 heads and a cable throttlebody. It is the Holdenspec engine. I am curious what experiences are of others regarding idling. I have a MBE ECU btw. At what revlevel are your engines idling. Mine is now at ca. 900-950 rpm. I managed to get it down just a bit. It first was idling at 1000rpm. My expectations were that an engine like this could idle at 800 rpm dead smooth. Maybe even a bit lower. To me it is annoying and other people also notice that the engine is idling at rather high level. Tel me what your experiences are.....

[Walford]

LS idles at 840 in my car below that i get clutch judder over speed bumps and gentle clutch engaugement
ye i know thats the paddle clutch,

Edited by Walford on Saturday 21st January 07:33

[flyingdutchie]

What ECU are you using?

[Walford]

Motec

[Brummmie]

flyingdutchie said:

I have the LS 6 litre with the LS3 heads and a cable throttlebody. It is the Holdenspec engine. I am curious what experiences are of others regarding idling. I have a MBE ECU btw. At what revlevel are your engines idling. Mine is now at ca. 900-950 rpm. I managed to get it down just a bit. It first was idling at 1000rpm. My expectations were that an engine like this could idle at 800 rpm dead smooth. Maybe even a bit lower. To me it is annoying and other people also notice that the engine is idling at rather high level. Tel me what your experiences are.....

If you are on a stock cam, you should be able to go lower than that.
800rpm should be easy enough.
Can you not just wind the screw out?
You might need to plug your laptop in and play with the fuel/timing just to get it fine tuned.

[Walford]

Has somone drilled a bigger hole in the butterfly
or
Has air idle control valve not been blanked off correctly

[Walford]

some Aussie maps

Think most poeple end up with 3 maps
1 road
2 track
3 wet/cheap fuel, when you carnt find Vpower and end up in tesco,s

http://forums.v8owners.com.au/showthread.php/timin...

[flyingdutchie]

I did get it down slightly by screwing the screw on the throttlebody. If I try to go below the rpm's I mentioned the engine stalls. So, I think it has to be in the ECU settings to get it lower. I am not very good at playing with ECU's. I can load an other mapping in the ECU or (en)(dis)able lambdafunction. That is where it stops.

[Brummmie]

I can get mine to 4-500rpm, but i prefer more so i can use tickover in traffic so am at around 8-850rpm, but i am on ITB's which run nicer.
But yes it sounds like you need to play with settings, as i say timing/mixture.

[flyingdutchie]

Thanks for the comments......

[Walford]

,

Good Quality wide band AFR, would be were i would start
somwhere were both driver and passinger can see it

.

Edited by Walford on Sunday 22 January 11:49

[tinker-27]

have a look at the idle control some ecus use ignition to help control the idle and you may have strange numbers in yours, the advance might be holding it up. also check for air leaks on the manifold as the seals can leak and cause problems. evn with wild cams they normally idle ok . its not a FAST throttle body is it ?

[flyingdutchie]

Yes, it is a FAST throttlebody.....

[Brummmie]

flyingdutchie said:

Yes, it is a FAST throttlebody.....

Craig is asking because they can be a bit "sticky", they do not always return back to the stop as they should.

[teamHOLDENracing]

Air flow on my race LS3 is sufficient to overcome the internal spring in my FAST throttle body. They are notoriously weak so had to fit an additional external spring to ensure the butterfly closed when off the throttle

[flyingdutchie]

There is an external spring fitted to the "butterfly", where the cable is attached. So, I guess that should be ok.

[Walford]

Most aftermarket ECU,s come with "sites" for fuel and ignition at 500rpm then 1000,1500,2000,2500 up to top revs

To get good idle you need to add sites at idle speed say 820 then one just below say 750

and maybe one just above

the lower site (750) can have slightly more ing timing in

Best to keep an eye on Air/Fuel when playing with ecu setting, and keep a backup map

[tinker-27]

Fast throttle bodies are a pain In the ass the spring on them is not strong enough on any Ls , ALL the Ls motors that I have seen them fitted to stick I won't fit one myself as they don't return to idle if you slowly return throttle ( if you flick it it will return). You can fit an extra return spring which helps . Normally if you spend time and get the fuelling correct and set the idle control it will idle well even cars with super light clutches and no iacv will be fine ,

[tinker-27]

What cam you running ?

[flyingdutchie]

Sorry guys.....it's a Wilson instead of a Fast throttlebody. The camshaft is the oem (standard) one. So, it's a very mild one.