ohh right - i did go out to autocross the car that weekend - unfortunately i had only one run before i was getting some warnings on the dash and decided to bow out. i eventually cleared the code and went back in but i couldn't really push the car a whole lot. i got a nasty powerslide in during one of my runs, but it's hard to say how much that was from the acd reflash rather than my cusco - the car feels smoother than it did with the gruppe-s flash though. unfortunately i couldnt play with the settings and try things out as much as I would have liked, but I hope to be running 100% again soon

 

That sucks. Was the code related to the acd at all? I forgot, did you have the gruppe s street or race flash?

 

I didn't read the whole thread but, will this ever be available for JDM CT9A's if it isn't already?

 

Yes, it's available for all evo's with acd.

 

What sold me on my Evo was not really the turbo but how well and quickly it steers. With that in mind if I get an ACD street flash will the steering be changed positively or negatively? I don't push my car so hard on the street that I feel a lot of under steer. With the flash will the car feel like it can be rotated easier with the throttle on dry pavement?
The Tarmac mode already feels tail happy with the stock tune in the rain.

Without giving up your "secret sauce" can anyone from ACD explain what is being changed in the tune. Specifically the street tune?

Thanks.

 

The maps that are changed for all flashes are the AYC map, steering degree mapping, acceleration maps, deceleration maps, and pump pressure maps. The steering will be positively changed to answer your other question.

 

My experience with Matt's ACD flash was that there was no longer so "much ado about nothing" on the front end. The car became more stable, was less likely to follow ruts on the freeway where it is a complete non-issue now, felt much more like a good RWD car rather than a hyper FWD with too wide tires.

From a layperson's point of view I feel that the issue with the stock ACD is that it opens up the center diff too much for too long after steering input, making the car essentially FWD rather than AWD for a period of time - makes for light steering but essentially forfeits the goodness of AWD.

Steering, if anything has more feel, a bit more weighty almost like more caster is dialed in. This may not be everybody's cup of tea but I am sure Matt can dial in what you want to some extent. After the ACD flash the car reminded me of an E30 M3, a car which I still consider to be the benchmark for handling feel to this day ... except that the Evo has way more grip.

 

My ACD lights just went all-on on the trackday this weekend at Mid-Ohio and I came across this thread while researching my next steps. While I hope nothing is seriously broken, the car was definitely being slowed down on my post-pump failure and there was some kind of whirring noise which I hope isn't critical. Just gave my car in to Pure-Tuning (Toledo, OH) and keeping fingers crossed. Maybe it's also time to get / see if I need an ACD tune after this. Awesome read - thanks Kyoo!

 

had first track day with acd tune...no bull s__t...does what it said...car noticably better mid turn and exit...worth a second a lap first time out..with more track time could easily be 2 seconds...stock diff...would recommend to anybody that tracks...

 

Heard from a very respected socal suspension evo guru that says acd tuning burns up the pumps and that you'll never know because there wont be any indicators of pump friction material loss.

 

^ interesting if true.

 

Just like upping the power on an engine can can shorten the expected lifespan, so to can tuning the ACD. There's a company in the UK that does high performance pump rebuilds.

Dave

 

I wouldn't say it wil burn it up... The pump MIGHT work more, however, it will not work at significantly higher pressures, for sure, as there is a mechanical limit to what pressure it can make..

I have opened pumps with 180000 km + (on normal road cars) and there is no significant internal wear, compared to pumps that did 40000 km... And both were opened because of corrosion problems...

as with everything, it is user's choice.. A stock engine with FP red will last less than with stock turbo and boost... right?

 

I don't know about the flash tunes that are out there, but in the MOTEC you can specify higher pressures. With the MOTEC MDC controller I have, any time you try to load a map with a lock value of 60% or higher, it kicks out a warning that it will shorten the life of the pump (or something like that).

Dave

 

well, I heard about it too... However, local grN racers never actually had any problems with pumps, and as I said, you can not get more than 20 atm out of it anyway... The pumps have a pressure sensor that is used to regulate the pressure, and there is some room to increase the presure, by 2 atm or so..

I am not saying you are wrong, just that it might not be all that dramatic, as stated in some posts I found on the web (like, pump life counted in hours etc..)

One thing that might be impacted is motor life.... it it works more, it might impact the electric motor brushes, rotor contacts etc...

One thing I noticed is that there is no real difference in pump wear betwen RS (which is ACD only) and GSR models (that have AYC also, and that thing works all the time).... talking about non US models of course..

Anyway, I'll give ACD/AYC tuning a shot, might be "interesting" WIll keep an eye on pump wear..