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Initial D 4th Stage comments... - Archive Topic (Locked)
Just_J:
--- Quote ---Because an ALS system destroys the engine,When the driver lifts his foot from the gas pedal the ignition timing is altered with sometimes 40° or more of delay (retard) and the intake air and fuel supply mixture is made richer. basically it sends unburned gases through the inlet. heres some points why it cant
* A quick rise of the turbocharger's temperature (which jumps from ~800°C to the 1100°C+ region) whenever the system is activated
* A huge stress on the exhaust manifold and pipes (mounted on a street car a bang-bang system would destroy the exhaust system within 50-100 km)
*The turbo produces significant boost even at engine idle speeds
*The explosions which occur in the exhaust tubes generate important flames which can, sometimes, be seen at the end of the exhaust tube
*Reduced engine brake
see thats why. Thats the reason why WRC cars change their engine after every rally. Anyway ALS is now old-school, a new method of keeping the turbine spinning is hitting the scene, Exhaust Gas Recirculation (EGR), its much forgiving on mechanical parts than ALS. But hey u can never get tired of the ALS going off (what a sweet sound).
Anybody who says they have a real ALS system on their car is BS, just not possible, maybe ur engine will last for say 100-300km max.
sry for the long post
--- End quote ---
Good post, but you're misinformed on a few things. Many street cars use the retardation method of ALS, but WRC cars use a bypass to get clean air, fuel, and spark into the turbo up-pipe.
You're mixed up on EGR. It's not a anti-lag system, it's a method of improving emissions on street cars. A large number of cars have EGR systems. It's designed to make sure all the bad stuff is burned out of the exhaust. My old Escort had an EGR system.
Lancer Evo's up to version 6 had ALS built in, but disabled in the ECU. It's not too detrimental to the engine, compared to how it beats the crap out of the turbine. I know a guy who has the ALS enabled on his EVO III, but he only turns it on when he's autocrossing, or rallying.
Also, the system can be altered so no boost hit's the engine at idle. ;)
Engine breaking has to do with compression ratio, not boost. When you lift off the throttle, the engine cuts fuel drastically, so even with all the air in the world, there isn't going to be enough combustion to prevent engine breaking. Besides, the idle control on most cars would stop the turbo from passing more air than needed.
Just_J:
--- Quote ---Well, i was just trying to say that they dont have to care about restrictions for normal cars in terms of pollution and noise etc. you said it yourself: rally live is loud, ALS would be illegal, gronholm was stopped for racing with illegal parts.
they race on public roads, yes, but remember: they are closed for traffic ;)
i dont want to argue with you since i really dont know much about rally rules and can only talk about the land i live in, but there is no way a rally car could pass an emission test here or even the security check since it has no catalytic converter and stuff
--- End quote ---
WRC cars have to meet city regulations because they drive on public roads to and from the stages. They do have a 3 way catalytic converter, and the volume level is regulated. :) Of course since they aren't true road cars, the rules are bent a little.
Oh, and I don't recall Gronholm ever being stopped for illegal parts. He was stopped for driving with a seriously damaged wheel, and he (and many other WRC drivers) were stopped for speeding between the stages.
Just_J:
--- Quote ---Hellbent one thing - the rally cars are semi-automatic (at least in WRC which is the highest class of rally) they are...what that means is they have paddle shifters like you can find in newer "sports cars".
But the cars still have a functioning clutch and manual shifter and in the event the tranny gets fubared mid stage they switch to full manual on the fly...its pretty cool the co-driver takes the handle off the e-brake and screws it in place for the shifter...bam standard transmission
--- End quote ---
Slight addition. The trannys are sequential manual, not standard. So when they do the conversion (what you mentioned is done in Fords, Citroen and Peugeot have a little stick), they push up and down on the stick to shift. The only exception to this is the Impreza. Come to think of it, I'm not sure it has a manual backup, I've never heard of the tranny hydrolics failing.
I wouldn't call them semi-automatic. ;)
Elchfaenger:
--- Quote ---
WRC cars have to meet city regulations because they drive on public roads to and from the stages. They do have a 3 way catalytic converter, and the volume level is regulated. :) Of course since they aren't true road cars, the rules are bent a little.
--- End quote ---
They do? Thats really hard to believe, even if i dont know the equipment of a rally car. Wouldnt such a cat get extremly hot? I mean even a normal one reaches easily 300+°C. And more important: A cat dies immediatly when it comes in contact with unburned fuel. And this happens on a rally car, or not?
Just_J:
--- Quote ---
They do? Thats really hard to believe, even if i dont know the equipment of a rally car. Wouldnt such a cat get extremly hot? I mean even a normal one reaches easily 300+°C. And more important: A cat dies immediatly when it comes in contact with unburned fuel. And this happens on a rally car, or not?
--- End quote ---
The cat is integrated into the silencer (muffler). ;)
They don't die immediatly when they encounter raw fuel, it takes time.
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