$12p Coasting idle speed

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VX L67 Getrag
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Re: $12p Coasting idle speed

Post by VX L67 Getrag »

NEED TO MAKE SURE THE VE THAT IS SET AT IS WHAT IT'S ACTUALLY SEEING THOUGH!

So long as you have it all set up right, yeah it all works as it's supposed to!
zspanners
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Re: $12p Coasting idle speed

Post by zspanners »

Hi Holden202T,yes poor vacuum at idle.
In neutral we have about 60-65 KPA and in drive about 75-80 KPA.
Idle speed is 1050 in neutral and 950 in drive.


Hi Dylan
What exactly is closed throttle VE and how does this work??
I assume that at closed throttle it will use these VE values instead of referencing the MAP tables??
VX L67 Getrag
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Re: $12p Coasting idle speed

Post by VX L67 Getrag »

LOL about idle map reference, must be a big cam!

Yeah closed throttle VE will run off that table instead of the actual full VE table if option is set can save a hunting idle so it's not going over many different areas!
Helps stabilize idle on cammed cars but not sure it will help hanging idle more likely to look at other suggested throttle area!
Dylan
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Re: $12p Coasting idle speed

Post by Dylan »

My idle used to jump around the 80 - 90 kpa at 1200rpm and if I touched the brakes it would die.
I copied the VE from the 75kpa row into the closed throttle 'VE table after I enabled it.
It now idles great at 1000rpm and touching the brakes don't worry it anymore.
Holden 304 with Crane 288 cam.
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Holden202T
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Re: $12p Coasting idle speed

Post by Holden202T »

yeah these cams are pretty big :P

the other thing i have found with motors that are low on vacuum it helps to have the throttle open more than the IAC.

for example, i'll get the idle right down by unplugging the brake booster or something, so the iac closes right up, then unplug the IAC, then adjust the butterfly so the engine is just below its idle rpm, so if you want 950 in drive, set it to 850-900 from the butterfly, then once the IAC is back on it doesn't have to do as much, the reason for this is if the butterfly is too closed and the revs drop quickly the motor can often stall before the iac can catch it - i've had this alot with my gemini on the dyno or after a big burnout then backing off hard.

its probably worth also getting the idle stop where you want it, then clear the ecm and then re-start, let the iac sort itself in park, then put it through all the gears a few times, leaving it in each for 10-15 seconds so the IAC can learn etc. also turn the a/c on and off to see how much that effects it. theres plenty of settings for IAC tweaking to help it all.

most the ones i've encountered were crane 286 cams, but they are totally able to be tamed, i've never needed to use closed TPS VE, but fueling needs to be right or they wont be happy, and they'll want alot of timing at idle!
Dylan
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Re: $12p Coasting idle speed

Post by Dylan »

My throttle stop is wound right in still have around 40 steps at idle from memory.
They do like timing I have 29 degree at idle and 45 at max.
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Holden202T
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Re: $12p Coasting idle speed

Post by Holden202T »

just be careful winding it right in, i found with mine too far in and the tps starts reading 1-2% and then the idle starts going all over the place! i ended up drilling a 3mm hole in my butterfly when i last had the inlet manifold off the car, this has helped alot!
Dylan
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Re: $12p Coasting idle speed

Post by Dylan »

I was wary of the tps setting but the diagnostic screen says 0% so think im ok
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Holden202T
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Re: $12p Coasting idle speed

Post by Holden202T »

my TB is a 70mm bored out unit so chances are the tps is slightly different to a stocker, but yeah just putting it out there :)
Dylan
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Re: $12p Coasting idle speed

Post by Dylan »

All good mate I'm open to any help in any way.
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