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Rotational Idle & Cats


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There is an EXTREMELY detailed and very good write up about anti-lag systems in Zoom magazine No. 59...

The anti-lag is stressful on alot of the exhaust parts (turbo, valves, manifold, exhaust, cat)... These days if you buy a good turbo like a Garrett, Trust or HKS they can withstand the anti-lag... But i wouldn't even dream of running anti-lag on the standard nissan ceramic turbo, it would blow it to pieces...

Well if your already running rotational idle you should already have a 10-15% opening so you wont need the kicker solenoid...

When the anti-lag is working the engine retards like 20-40degrees (on some cars) and dumps a heap of fuel into the exhaust manifold which then ignites on the hot manifold and more importantly on the turbine wheel which then produces boost... The car won't be ready to produce boost, it is producing boost...

Yes anti-lag is beneficial at the drags coz for the launch you want the turbo to be fully spooled for when you dump the clutch...

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GTS-t VSPEC, so you are running a Wolf computer, can you tell me your experiences with it,

Its at the top of my list for ECUs right now. Looking at buying one in about 2-3 weeks. I havent read anything about them having rotational idle, or any other functions you mention.

Are the memory cards that easy to change over, what $$$ are extra cards worth.

Id like to have a Map setting to run say 12psi on road on 98 octane fuel, and the a track MAP setting to run 1.3bar on VP race fuel.

I ran MT8 on my old Skyline and was never happy with the quality of the tune you could get out of it. Not the most accurate fuel delivery and no matter how much tuning (by experienced tuner) you coudnt get it returning any decent economy figures as the thing didnt run closed loop. Sure did the job though when foot flat to the floor:D

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  • 5 months later...
Originally posted by Dragon

Hmm, I was running rotitional idle and anti lag on my little GTti.

Rotational idle was used to spool up the turbo on a standing start. >12psi from the word go! (Then it would hit 26psi @ 5,500rpm)

Anti lag was used between gear changes to keep the rather large hybrid turbo spinning.

I would use the rotitional idle as a crude form of launch control. The MoTeC M4 Pro was set to cut the coil packs, but still allow fuel to pass through.

While staging, you would hit the launch control button on the steering wheel, engage 2nd (Never first gear) clutch in, and foot flat to the floor on the loud peddle.

The MoTeC would hold the revs around the 5,000 rpm mark, but keep on cutting the spark to the cylinders at random. While the throttle was wide open, the resulting pulsing from the engine would cause the turbo to spool while you are standing still.

As soon as the clutch engaged (A micro switch on the clutch peddle) the MoTeC would then switch off rotitional idle and run the proper maps. (IE: 9,500rpm cut, and anti lag turned on)

I used rotitional idle to gain boost while standing still.

Worked VERY well, but produced 6 foot flames out the back. (Cat died a long time ago)

Had a 5-8 second window of using rotational idle, over that, everything started to heat up badly.

Anti lag 'can' be used to get the turbo to spool up before launching, but is a very crude form of doing this, since you have to rev the engine right up, then lift off the loud peddle to get the antilag to kick in.

At least with rotitional idle, I had the throttle wide open all the time!

WOOOOO DUDE"S!.... I think I've seen this car. its being a few years but, there was this little blue GTti charade that used to blow the doors off V8's and WRX in the ACT... the driver was a nut bag :) .... Man you had to see this little machine fly

Its couldn't be the same car could it? your in Qld

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Originally posted by GTS-t VSPEC

It's been dredged up from sometime last year.

By the way, I can highly recommend removing your cat. Boost come on much sooner:D

*meow* seconds that opinion. flame me up scotty!

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