RjRacing05

iTrader: (4)

So last week i decided to take the next step in improving my handling and track times, so was looking into doing some ACD tuning and/or TRE rear diff. I did some research and spoke to a few people and decided to do a new flash for my ACD first due to cost and ease of install. I contacted [REDACTED] about uploading new ACD maps that would fit my cars set-up and power, he was quick to respond and had some good knowledge on the subject.

Located only 30 minutes from him, i decided to drive up there and meet him last weekend. Matt recomended installing the Level 7(circuit) and Level 8(auto-x) maps for my set-up and racing i do. The install only took about 15-20min for 2 maps, and then we went for a test drive afterwords... all i can say is WOW!!! The car has a completely different feel, more neutral and no push (understeer) when entering a tight turn anymore on either map, and when exiting under throttle the rear-end kicks out just enough for a blistering fast exit speed but never felt out of control and gives me tons more confidence. I only have about 200 miles on these so far, but its been the best handling/control mod to date next to my coilovers and I really cant wait for next track season so i can compare my log times from last season. There is also no diff noise like i have read about other flashes out there.

I will keep you all updated with the more seat time i get and once VIR and Summit Point open back up text season for the hard facts... the numbers, but on the street its been a whole lot of fun. Matt has a great product with awesome customer service, he even texted me later in the week to ensure i was still 100% satisfied and to with me a happy thanksgiving

Handling mods: ACD-Tuning Maps, Stance Coilovers (9k/10k), Whiteline Rear Bushings and Swaybar, Toyo R1R tires

Benja

Good to hear, I'm going to make a flashing dongle this Christmas break, and have similar mods to yourself.
Tein Monos 11/14kg, rear sway and a few braces.

TommiM

iTrader: (19)

I never had any differential noises come about due to Gruppe-S ACD Race flash. What was happening was, with the Race flash and stock rear diff, I would get a binding on really tight 1st gear autox turns. It seemed like the lockup of the agressive flash was not allowing the vehicle to turn. Think autoxing with a Detroit Locker or spool. After installing a TRE max lock 1.5 diff it went away.
In all fairness Gruppe-s did specify the race flash was meant more for a road course. Their street flash is closer for someone looking more to autox.

Which package did you end up getting form them? They seem to offer several packages depening on how many maps you want setup.

lan_evo_mr9

iTrader: (10)

Ryan,

I appreciate the kind words. Ryan currently has the autox map and circuit map in his acd unit. Snow left stock.

Matt

RjRacing05

iTrader: (4)

Right, but i still have the stock rear diff on my evo and have not experienced any lock up on tight turns with the ACD-tuning flashes level 8(auto-x) & level 7(circuit). Correct me if i'm wrong, but typically the auto-x flashes change more of the settings than the road course flash due to more of the torque being sent to the rear wheels for the tight turns and over-steer, so they are considered "more aggressive". Glad to hear the TRE 1.5way fixed your problem, but I'm not even sure if I will need a rear diff upgrade with these flashes... but again the track will be the true test.

kyoo

iTrader: (29)

I would say that the rear diff and the acd reflash complement one another - ie if the acd tune is allowing more torque to be sent to the rear wheels in a corner exit situation, a competent rear diff will be able to manage that power better - even if the rear wheels are receiving more torque, those rear wheels will be traveling different distances. How the car will oversteer is more of a setup issue in my mind - you can add more grip to the rear (ie, via a front sway bar), and let the car really ROCKET you out of corners. It's not as simple of a matter as oversteer or not (not suggesting that you think that way).

Gruppe-S ACD reflashes, yes, did have a binding issue for low speed corners. I think the reason the rear diff mod alleviated this was because as the front and rear were being locked together more aggressively, the rear diff allowed for great speed differential between the left and right wheels, which have a bigger difference in tight corners. At least thats what I think it did. In my mind the Gruppe-S flashes seemed to simply offer more performance just by increasing lock up, but not necessarily being fine tuned to take advantage of all the input the ACD gets.

Don't want to push the rear diff part too much for this thread, but you should at least note the stock rear diff was not assembled properly from the factory.

sba

I see you already made a thread about review. I will speak with the guys that are using my files also to come here and speak about it.

TommiM

iTrader: (19)

Im not so sure acd sends more torque to the rear. I dont think the acd unit acts that way. It just controls the lockup between the front and rear wheels based on steering inputs, speed, etc, etc. the transfercase is always a 50/50 split on the evo.

kyoo

iTrader: (29)

the power sent to the front and rear is always 50:50, but I believe the lockup by the ACD can change the torque? could be mistaken

lan_evo_mr9

iTrader: (10)

Yes, it is always a 50/50 split, but....

What we have is a differential controller that can be configured to control the torque distribution by adjusting the percentage lock between front and rear differential.

This is taken off the motec site- it explains it perfectly:
The MDC is used to adjust the torque split between the front and rear differentials to achieve greater control over handling characteristics such as traction, braking on loose surfaces, turn-in response, and understeer on both corner entry and exit.

The centre differential is essentially a limited slip differential with adjustable preload. The preload is proportional to the fluid pressure in the centre differential. The MDC works by regulating solenoid current, which in turn, controls the fluid pressure. When no pressure is applied (0% lock) the centre differential operates as an 'open diff'. With increasing fluid pressure (increasing percentage lock) the preload increases, requiring more torque difference between front and rear wheels before the centre differential will slip.

rush63

iTrader: (42)

^^^

How are the custom maps 1-3 done? Do you meet with the customer at the race track or are they combinations of packages for example, STAGE 2: Two Custom Maps = Street Package + Track Package?

lan_evo_mr9

iTrader: (10)

The custom maps are done to a customers specific list of mods, how they drive, and which track they frequent most. The custom stage 2 can be two basic maps or 2 custom maps to suit a track, car, etc.

Hope that helps a bit.

Matt

sba

I'm waiting for some more reviews!

RjRacing05

iTrader: (4)

Update: I've put about 1,000 miles on my new flashes now and still love the way the car feels and have had no issues. This flash was kinda like that makeup sex after a big fight that re-sparked your relationship... I usually find myself putting the car away for the winter in early November but I’m enjoying driving it so much it’s been hard to put down, I’m now waiting till the first snow

I agree with you 100%, with the more seat time that I’ve had the more I’m starting to realize how much I may benefit from a rear diff upgrade as it should make it alittle more precise and predictable. Originally I was so impressed with how the car was transformed from a understeering pig to an oversteering machine, I was alittle blinded by the fact that it’s not 100% in-tune with where you want to put the car during the power slide due to a lack of a mechanical LSD. So when I do decide to finally put it down for the winter I’ll be installing the TRE rear diff and my 2.4LR set-up I have sitting in my garage.

Dragon-V

I have been ACD mapping since the end of 2010 with the help of Sabin and have done hundreds of hours of testing on the road and track.

This year was a very successful year for us in the UK with 2 cars running in a Sprint series that had ACD mapping

The Class B car ( 2.0l stock turbo) had 5 straight wins and won its Class our other Class C car (2.0l GT30) started midway through the season and had 3 Class wins, 1 fast time of day and won Class C we also had another win in Class B and a 2nd place as well.

So out of 7 rounds we won 6 and of the events and the Class B overall championship. Again with the Class C car we won 3 events and overall

So when you work it out over the 7 events running 4 classes we won a 1/3 of them

ACD mapping is the way forward if you want to win and make the ACD work how it should work !!!

Lee