fantrman

iTrader: (27)

Thought you guys might be interested in my impressions of the ACD-Tuning autocross map. I installed the re-flashed ACD last week and had a chance to use it in an autocross this weekned. First off, I’ve been autocrossing RWD cars (E36 M3 & TR6) for about 18 years and thought I would take the Evo out for a try a few months ago on my everyday street tires. To be honest I was very disappointed. My FP Black make lots of power and I knew it would be laggy for autocross, but I also found the over steer to be a real let down, as others here have said. The car would push very wide when the power came on and I would have to let off to keep it on course. This didn’t let me power out of the turns. I had to use harsh trail braking to get the front planted at turn-in, get the rear end moving and then wait for the power to come on. Slaloms were also a real chore. Granted, I am still getting used to driving an AWD turbo car, but it was really really hard to drive fast. At the time I already had a larger RSB, Swift springs, flipped the front strut bolt and rear bumpsteer correction. Time for more upgrades…

Over the next few months I added the TRE 12-plate MaxLock, Bilsteins, a larger FSB and ACD-Tuning’s ACD Autocross map. I had a chance to autocross it for the second time this weekend, again on street tires. Holy Cow!!! The car is now transformed! It was great. I’m still getting used to the car and it still has too much lag for autocross, but the handling is wonderful. It felt considerably different than it did at the last event. The local events here are very fast 70 to 80 second courses with mostly offsets and slaloms – lots of third gear and some very high second gear.

This weekend’s event allowed five runs and provided the opportunity to play with the new ACD autocross map. I had ACD-Tuning insert their autocross map in place of the stock “Snow” setting since we don’t see much snow here in SW Florida. “Tarmac” and “Gravel” remain stock. I decided to take the first run slow in Tarmac and then go full speed and alternate between the Tarmac and the new autocross map for the remaining four runs. I ran on Potenza RE-11 street tires, set all pressures to 38 PSI and maintained it throughout the day. Again, the first run was done slow in Tarmac to learn the course. The second and fourth runs were also made in Tarmac, but at full speed. Here are my impressions with the ACD set to Tarmac: the car was very controllable and neutral. Again, I was very surprised how much better the car felt from the last autocross. Overall, I would call it a great base handling setup. I was able to drive the car fast and didn’t have to deal with under steer or worry about over steer. The car would 4-wheel drift at will – very nice. The third and fifth runs were made with the new autocross map. I didn’t notice a huge difference, which is good, but I was now able to swing the rear end if I wanted to. I was expecting the car to over steer too much with the autocross map, but I was pleasantly surprised it didn’t. It felt controllable, neutral and I now had the ability to wag the tail. I could now steer the car with the gas in a sweeper. It worked really well in the slaloms. In the end, my runs with the ACD autocross map were about 0.3 seconds faster than those in the Tarmac map. My best time was 72.677. Again, not a huge difference, but it may have been more if I were more comfortable with the car and could take more advantage of the benefits.

Also, just to be fair in this comparison, it should be noted that ACD-Tuning also remapped the AYC which improves all the stock ACD mapping. In other words, my stock ACD Tarmac setting was modified to be more agressive too. So in my comparison, this likely reduced the performance difference between the "stock" Tarmac map and new autocross map.

Regardless, I still have more testing and adjustments to do of course and will continue to learn the car, but it seems like everything is working together well. I find the ACD autocross map as a very convenience tuning tool. I can adjust the car from neutral to slight over steer at the push of a button.

CosmosMpower

iTrader: (1)

Interesting write up. Is this part of a reflash that they can do when they tune your ECU? Are you saying the difference between the stock ACD map and this remap was worth about .3 on a 70 something second course?

lan_evo_mr9

iTrader: (10)

The difference is more...way more. When you alter or tune the AYC map, it effects all the other maps in every mode. You can get the car to handle well just by messing with the AYC map, even though our cars(evo 8/9) don't have it, it changes how things interact with each other. It's hard to describe all the technical workings of the ACD unit itself without getting 'geeky'.

When you look at the rom of an acd unit, you have one AYC map and then 6 maps per mode(tarmac,gravel,snow). By tweaking the maps in the mode, you can get the car to behave just a bit different to suit certain cars, racing styles, etc. When you alter the mode mapping it then compliments the AYC mapping. Hope that makes some sense

So when Tom says he was on his 'stock' tarmac map, it's not really true since the AYC map was altered- none of the maps are stock anymore. What he was saying is that the 'stock' map was .30 slower than the dedicated 'autox' map. The whole car is faster than before, but the dedicated map performs better due to changes in the mode mapping

fantrman

iTrader: (27)

^^^^ What Matt said.

I wish I could have provided a more back-to-back test for you guys to better isolate the performance enhancement of the ACD re-mapping, but the fact is I changed a few other things as well from the previous autocross to this one. However, I can say for sure the car is wonderful with it and works very well with the other mods. And, I have the ability to adjust how much over steer I want with the push of a button. Its a great tuning tool at a bargain price IMO.

ratt_finkel

No offense, but it sounds like you made lots of changes since your last Auto-X. Hard to say what actually did what.

fantrman

iTrader: (27)

None taken at all. Yes, that is what I was trying to say. As I see it, there are two main things of valve I got from the revalvation: 1) ACD tuning/map switching is a great tuning tool to change handling on the fly - it really works; and 2) regardless of the AYC retuning ACD-Tuning did, the ACD autocross map was faster on my setup than the ACD Tarmac map (in this case 0.3 seconds).

I see others are also starting to test the ACD-Tuning maps. Maybe others will be able to do a true back-to-back test by switching ACD units same day, same event and report back. I'll offer to do such a test if Matt wants to send me a totally stock ACD unit to switch out at an event (two runs stock; two runs re-mapped).

CosmosMpower

iTrader: (1)

What is involved in remapping the ACD maps? Is it just software? 3 tenths is pretty significant if all else was the same. I bet there's more time to be gained if it was pushing wide on power application before and you can get on the gas a lot earlier now.

fantrman

iTrader: (27)

Well, as the end user, it just ment swapping out the stock ACD control unit with a re-flashed one. The ACD-Tuning website explains that. Its only software, but I don't know what is involved in remapping.

ratt_finkel

It should be noted that this is not legal in SCCA's stock, ST or SP classes.

I'd love to test it but it's not legal. Honestly, I find the ACD to be too intrusive. (I'll do the driving thank you). It seems most notable in slaloms.

sba

Thank you very much Mr. Fantrman for the review. As you may know or not, i'm the man behind the tuning and i am pleased that you gained what you needed for autocross.

For any other questions, feel free to ask.

Happy racing

S.