Aggressive Anti-Lag Theory | Fresh Air ALS Mountune [TECH NUGGET]

Turbocharging is a great solution if you want to make more power, but it does have some drawbacks when it comes to turbo lag and maintaining boost for instance response however in the case of World RX cars Mountune is one the case.

Antilag has been in common use for rally and rallycross for decades in order to improve boost response. Antilag works by bypassing air and fuel through the combustion chamber and igniting it very late in the combustion cycle so that it continues to burn in the exhaust manifold. This provides energy to the turbocharger to keep it spooled up so that when the driver gets back on the throttle there is instant boost available.

Normally this is achieved by opening the throttle plate or bypassing air around the throttle plate. This works well to a point and is pretty easy since it doesn’t require a lot of hardware to make it work. The problem is that if you want to increase the effect of the antilag you need to open the throttle more to bypass more air through the engine. Since the fuel and air is still combusting inside the engine, this creates engine torque just when the driver doesn’t want it - when they’re off the throttle. This can create unwanted ‘push’ which makes the car harder to drive.

The alternative, as used here on Mountune’s Ford world rallycross engine is to use a fresh air valve to bypass compressed air directly into the exhaust manifold. This means a large throttle opening isn’t required and instead the ECU can simply inject additional fuel which then mixes with the fresh air in the exhaust manifold and combusts. This can result in the turbo producing as much as 3 bar of pressure before the closed throttle, ready to provide an instant response when the throttle is opened again 🤓

#highperformanceacademy #antilag #mountune #learntotune #goodwood #fos19 #worldrx #rallycross #als

[rhubarbpie]

I hate when too much ear gets into my combustion chamber.

[admiraldirtbag]

This has got to be one of the first times I didn't understand the content. I need to watch this again!

[XHikotheproX]

I've never been in a turbo car that had maximum boost anything less than 2 seconds after WOT. Putting your foot down and having instant boost must feel amazing

[latemnf]

Some similar principles to secondary air injection systems or what a lot of people call 'smog pumps'.
Great video as always!

[TwinTurboZach]

Good info. Saw you at Titan motorsports at TX2K I think it was last year or 2018 before you were doing an interview, gave you a thumbs up and continued, didnt want to interrupt. I then saw you at PRI in December talking to some people. PRI was awesome. Crazy to think how in this industry you never know who you will come across. Love the videos, keep on it.

[rafaellastracom]

It's good, out-of-the-box thinking.

[coryhalvorson]

hp academy is pulling back the curtains on all the juicy racing secrets, many thanks.

[slowlearner]

So what you're doing is turning the exhaust and turbo into a jet engine. LOL awesome.

[jonodevenport]

As always, great informative content from the HPA team.

[indopleaser]

Video Request: can you do a video about WRC Subaru Rocket Anti Lag. and the WRC Focus Hidden Boost Tank. both are innovative and unique ways of using anti-lag to its maximum. really hope you make a video about this. i kindof understand what’s happening, but a full explanation from someone more knowledgeable will help the internet learn about this minimally discussed topic. Thanks!

[scorpionscorpionn]

In WRC they change turbocharger after each race as a consumable for this reason, can not be applied in street

[ricepony]

Andre’, can you do a video on the rocket style anti lag systems that were used in the WRC?

[leighpowrie]

Hi Andre! Love the videos. Been following since HPA first started up. Even taken part in webinars and some online courses. Love your work. However may I ask you do some videos of other hardwares on performance or race cars ie, brake calipers and shock and spring set ups. Not so much just on what they do. Thats fairly simple but more on technical advances in brands and misconceptions between brands and so on? For example I can’t decide on brake calipers mainly as there as myths and contradictions over what’s worth buying and what is or isn’t good. Or what is overkill and why. I think it could help a lot of people hearing unbiased info about things like this. Thanks heaps.

[garagecedric]

Similar to the audi quattro umluft system used in group B. However with modern control tech its much much easier to do such systems today then back in the 80s

[kemosabe]

That's awesome. I've always wondered what they use to achieve that. More on race engine secretes

[nmoran]

Guess that means you need a hell of an exhaust manifold combustion occurring outside the chamber that’s bananas

[philippericherpepin]

Wonder if you could achieve the same result with closing a few cylinder injector and using them as fresh air pumps

[tomjones]

Didn’t Toyota (and other manufactures) install fresh air anti-lag system from the factory on Celica back in the late 80s and early 90s. Haha.

[ShoshinMizu]

Guy in the back itched his butt like right when the video started

[sierraco]

It's true that the downside of conventional anti lag, with a throttle kick, that the car would keep pushing when breaking, but on the other hand, with a throttle kick, the response is much better coming out of a corner. Some racers would set a throttle kick even without anti lag activated to get that extra response. It seems that a fresh air anti lag would eliminate the throttle kick along with its benefit!