all I really know of anti-lag is that for drag racing it works well.
YouTube - Turbo S2000 Run 10.7 @ 129miles
that's my mates S2000 on this run he ran antilag setup through his ECU so he had boost off the line. you notice the backfires.
But all other anti-lag is on top pro rally cars. yet under most of there rules conditions - they need it so they have god sort out systems to keep them on boost.
I don't see why you need it in NZ - then again most of your roads are like rallys.
They do put alot of stress on your turbocharger but. I know a few people running group N type production rally cars in both national and smaller loacl compitions and most can use it but they don't because the cost of killling a turbo for that minor bit of performance is not worth it. Most just drive around the lag. but most of the cars are setup for almost no lag right ratios' etc.
That bit on the GT4's it was an option for rally owners. When they bought there GT4's for rally use Toyota had a number of options. They could option the ECU for examples and the hi-spec Denso unit was mapped for more boost and more torque but did not meet emissions etc. This was I think on the St185 or St186 only the first model with air -to air top mount, beofre they went Water to air. But on the later model about 93 they went water to air cooler the whole setup was even stronger again.
Some of you noted early or lates 80's cars
Back then to clean up emissions they used vacuum pumps or air pumps to pump in freash air into the exhuast system so not only did you loose power from bad pre Cat exhuast you lost 1-3hp at the crank driving this pump.
The thing is people have turned them into anti- lag type setups with right retard and extra rich fuel it works well.
but again of course the main issue with anit lag is turbo damage to the turbine - not so much the housing as it can take the sudden change of temperature - well it can take it better then of a turbine.
Don't try it on ceramice wheel RB garrett turbo.
But to give you an Idea you can turn a turbocharger into a Small jet engine.
you plump the compressoe outlet into venturi of small chamber basicly a nossle add a injector for fuel- feed into another smaller outset so air fule mixes behind it add glow plub for ignition or spark plug then plum the out let to the turbine inlet and make small after burner exhuast and mount to device - feed it gas and one quick spark.
Jet enigne now it was comon to do this at Qanats by apprentices to find away to improve it etc and see if you can make it last.
Results we made the injector not melt by pre mixing before spark or igniton area.
that's all we did and it last 2 mins more the early guys. Turbine wheel melted - lost compressor pressure flame caught up to open injector - ONe bit bang.
only good big on turbo was compressor and rest was stuffed. Even the oil feeding the bearings could not keep up.
Anti lag is very similar.