Reading this article:
http://www.vwvortex.com/artman/publi...icle_330.shtml

It mentioned that Evo VIII has viscious center, limited rear and open front diffs, vs Electronically controlled differential w/ AYC that is found on Japanese and European versions.

Could somebody give me more insight on that? Is it worth changing U.S. parts for Japanese spec diffs?

If EVO VIII does 1:55s on a local track, will AYC shave off a second, or more?

I have U.S. EVO IX, from what I know it has same diffs as U.S. EVO VIII.

Thank you!

 

I didn't read your link but 03 and 04 Evo's have the transmission setup that you mentioned, excluding the 04 RS, which has a mechanical limited slip front diff. 05+ Evo's have a mechanical limited slip front diff and an electronic active center diff, hence the "tarmac, gravel, snow" settings. This diff controls lockup speed depending on the settings. AYC is not included in US spec Evo's and quite frankly would not be worth the cost and headache of trying to retrofit.

 

Is the rear differential for the 05+ Evos a 1.5 way clutch type differential?

 

why would it be so hard to put the jdm spec parts on our usdm with the proper ecu

 

one word "warranty"

 

AFAIK AYC is a hydraulic pump based system like our ACD in the 05+ models. One reason AYC was not included in US spec Evo's was that those components wouldn't allow all the US evap systems to fit. So not only would you be stuck trying to track down all the proper lines, pump, planetary gear rear diff, etc., you'd also have to remove your evap system and most likely retrofit a good deal of the AYC stuff. IIRC many well known racing teams remove AYC in their race cars, for what thats worth.

 

Usually in Japan the companies that run time attack Evos use the RS model, which does not have AYC. They say that AYC actually decreases performance, because AYC tends to interfere with the drivers inputs.

 

I also heard that the AYC can't handle as much WHP as the Mechanical which makes sense. It also makes it harder for tail out shenanigans. It does help alot with turn in.

 

^ ROFL @ "tail out shenanigans"

 

my question is how much different are acd and non acd equipped evos

 

the Puma evo track car in japan have AYC...
but the advan rally car do not have it.
for the pavement is good to have it.
but if you don't have it don't sweat on it.

acd vs non acd cars the difference is noticable but not major.
better driver will win no matter wich car he drives.