Anti Lag - Be Careful!

[KEET]

Hi Folks,

 

Just putting a flag up to let everyone know to be careful in the set up and use of Anti-lag now I see this is starting to become popular.

 

I spent a fair bit on a refresh of much of my mechanicals and went with a two tunes (PCMTEC) at 320 and 350 RWKW. 

Both tunes great and the various mechanical updates shone through with a much improved powerband; car felt really strong; tuner did a great job.

 

Unfortunately, having used the the anti-lag a couple of times only in the first couple of days post-tune car sounded a bit lumpier, I put this down to probably my ears not being used to the after market turbo back exhaust being somewhat louder than stock.  In hindsight, it was very likely the loss of one cylinder.

 

A week or so later I tried the anti-lag again.  This time large bang having blown the hose the joins in to the throttle elbow.  Cleaned and reconnected, engine now sounding as lumpy as a top fuel car at idle.   Yep, I had now turned my lovely I6 in to an I4.....

 

So now I'm due in in Jan to "build" the engine for a tidy sum.    One comment I have had is that it will be worth putting a boost gauge in to understand when the boost has built up.

 

I don't really know just how such a damaging over pressure occurred and whether there should be some secondary safety release above a certain pressure as part of the build, however I urge anyone thinking of adding anti-lag to get a boost gauge and discuss and consider carefully before going ahead and to consider the addition of boost gauge as part of the mods.

 

Only myself to blame! But not too happy given I used the anti lag probably no more than 5-6 times before I was the unhappy owner of an I4.

 

Despite "building" as part of the forward process, I'm interested if anyone has any thoughts on how to safeguard by design; even now planning to build to a much higher rating, I'll still be very hesitant to pull that paddle again.. 

 

Yes I know it sounds obnoxious!

[k31th]

yeah, that sucks... but if you didn't know Anti-Lag is destructive to pistons/exhaust-manifolds/turbo's etc then your tuner should have told you this in the process of getting you setup for it, imho.

[hjtrbo]

ouch. Not having played with anti-lag myself, not sure how much of a band there is that goes from mid to wild. Should there be room, then first thoughts are it's on your tuner.

[El Andrew]

Yeah I reckon there's a fair bit more to unpack here before jumping to "anti-lag is bad mmm...okay"

Something else in the tune, an existing mechanical weakness waiting to go bang, etc.

Without obviously knowing who you are working with, I'd be getting a couple of opinions on engine and tuning before throwing more cash in any particular direction.

[sixman]

Yeah, Iam worried the tuner has convinced the owner they did something wrong....

[KEET]

Thanks guys, appreciate your thoughts and for that matter your sympathies!

 

I guess I presented to the tuner as someone who knew what they wanted so (benefit of the doubt) there might well have been the assumption that I was more learned on these things than I actually am.

 

Tuner in question is very well respected in terms of conduct, outcomes and troubleshooting (incl by members on here) so I don't think any mal-practice or mal-intent.

 

Indeed there was already 170K on the engine, of which 60K was running a light degree of boost modification via injectors and SCT module.   I think possible there was a weakness in there but arguably unlucky to have popped one of the world strongest factory blocks from running only a 3576, and more recently upgraded to a 3576GTX compressor wheel.

 

I did Crack a smile at the Mr Garrison reference!

 

Quite by chance (honestly I'm not desperate to actually have anti-lag it was a bit of a stumble-on) I did see that independent motorsports are offering a turbosmart anti-lag valve (going about it a different way entirely). However they are saying "for motorsports" query road legal?  and for us there is no 6 cylinder outlet option (ironically I only have 4 cylinders to service at the moment....).   I daresay there would need to be some pretty whizzy controller module such that this would properly integrate.

 

https://www.independentmotorsports.com.au/turbosmart-anti-lag-valve-alv

 

This engine timing type antilag still leaves me personally a bit uneasy noting on the car I need to daily drive!

[hjtrbo]

Just having a guess here; I presume to make it work on the road a second solenoid valve would be installed that would activate the anti-lag valve from the PCM IMRC output via a multi-tune.

[gaz097]

I was in a falcon at powercruise and when he held the antilag it made something like 25psi at like 2000rpm.

It was very violent on tyres and everything and he broke a diff later in the day and he didn't really dump the clutch in it.


I would say it's only ok on a built motor and e85.


Happy to be proven wrong though.

[KEET]

Quick update on this then now the motor is out and under rebuild.

One bent rod, two pistons not holding pressure, and sigificant scoring to the camshaft.

 

Muchas regret!

 

I guess just hoping that the "built" spec I've gone to willl give me good future reliability if 575hp crank (as prior to the failure under anti lag) and 800hp rating to the build.

 

I think gaz097 is probably wise in saying built motor is the advice for running this type of anti lag (fuel timing based).

 

I daresay as time goes by there might be a more mechanically sympathetic system that surfaces that isn't just as random (throwing out unburnt fuel past the cylinders) in how it works (looking at HJTRBO comment).  Wouldn't it be nice if some parallel communities (2JZ, RB26 etc) were getting across this to help us keep up with the flighty modern B58s and lamda II 3.3 T-GDi (both of which I have had the brief pleasure of driving).

 

Any one any idea whether the PCMTEC anti lag is a standard software patch (for want of a better word) or is it a tool within the system that the tuner uses and the tuner codes in the parameters bespoke to judgment?

 

Will let you all know the full dollar damage when I pick her up in a couple of weeks. 

[Puffwagon]

Tuner tunes the antilag to suit the setup. You pay a bit extra for it as it uses a custom operating system within the stock pcm.