GT500R

Best would be custom real time tuning for what you have and what climate you are in, etc..

Sloooo4esT

linear is all at oncce, correct?

UrS4boy

No. Linear is a slow build in proportion to throttle position. Non-linear = on/off

tystager93

I know this thread is as old as time but. I was wondering about linear and non linear. What are the good and downfalls of each.

From what I understand linear spools more quickly which I would imagine wears the turbo out more.

Non linear gradually spools and is more of a swooshing build of pressure, thus reducing stress on the turbo and other components.

Then again I could be totally off.

UrS4boy

Your thinking is a little (180 degrees) off. I wouldn't worry about wear on the turbo or anything.

Linear = progressive, predictable, increase in boost = gentle but increasing push in the back.

Non-linear = ON/Off switch, no boost/BOOST!!!, laggy, hard kick in the butt.

If you are driving in the twisties, linear is easier to control coming out of corner. Non-linear = potentially dangerous, too much boost at the wrong time, hard to predict/correct.

That list still holds true but many of the suppliers no longer are there. But you can find used ECUs loaded with the various chipsets on eBay or Audifans marketplace, etc.

tystager93

Okay thanks, a friend of mine has a 94 s4 and has a chip he is willing to sell me. It says tuningchip eeprom on it. Dose anybody have experience with one of these?

I think I would prefer a Linear chip, as I plan on doing some HPDE events in the very near future. But I am not to picky about which one.

UrS4boy

Never heard of "tuningchip". Suggest that you pass. Find a pre-chipped ECU on Audifans market place or the like with a brand name chip set (from the list I posted). Such ECUs go for $350 to $500 depending on the presense of a 3 Bar MAP sensor or not.

EyeLid

Given you guys are in the US of course, but I'd say Hohenester Sport is also one of the in Germany when it comes to potent, old Audis, a bit alike MTM (but not as commercial on todays models).

Then we also have Schmidt Motorsport, who actually constructed the Audi S2, with their SMS Revo / Revo S setups. Then again, these setups are MTM programs from what I know.

UrS4boy

Schmidt Motorsport fit the first "3B" (probably an RR) into the first CQ on behalf of the Audi factory as the first test S2, they didn't construct ALL the S2s.

I haven't heard of anybody here (in NAmerica) having Hohenester Sport chips. However, many people got chips from a fellow named Bob Pastore that were based on a combination of code-broken (no daughter board needed) MTM and Thomas Schmidt Motorsport softwares. This combo is very agressive and leads to pinging in many UrS AAN engines. I know of one example in which an "RS2 (plus)" version of this combo caused so much pinging, the engine eventually through a rod. I had this version and while it could be tamed (somewhat) by mixing 9L of toluene with 71L of 94 ((RON+MON)/2) Chevron (with Techron), it was difficult to use when driving twisty roads because it was SOOOOOOoooo non-linear and laggy, it was like lighting a fuse on a bomb coming out of every corner, wait wait wait wait wait BOOOOOOMMMMM let's go!!! No fun. I switch to MRC (Mihnea Cotet) Stage 3 (RS2 hardware) software and drove the same roads - it made a bit less power but because it was more linear, it was much easier to control and the drive was much smoother and fun.

To round out some options, Paul Nugent at S2Central.net in the UK (N.Ireland I think) has "homefries" software that lots of S2 people use. There is also a fellow Dmitri (prj on the S2Forum) in Estonia who has broken the coding ont the Motronic ECU better than anyone I have heard of and is now tuning AANs, ABYs, and ADUs in Europe. He is also affiliated with Addict Motorsport Design in Woodinville Washington (north of Seattle http://www.addictmotorsport.com/contact.html). AMD can tune your car on a dyno, and burn new chips to suit.

MRC has a distributor in the US, Bob Myers at Chips-Ur-S.com (http://chips-ur-s.com/Entrance.html).

S6Raptor

Dave do you know anyone that has gotten the Intended Acceleration stage V? I'm curious as to price. 420hp...that makes me drool.