VonK :: Retired

Is the "M" ECU programmed to advance ignition according to a fixed map, or does it continuously advance to detonation and then back off a bit (within a range, of course), or does it do both? Please say.

Thanks.

DrMerl

If I remember my ABCs right, most programs are going to advance ignition until a predetermined point, not till detonation is "heard". That point and how quickly it advances or retards can be changed by a tuner. Read - better throttle response, but requires better gas. Unless major advances have been made in the device that "listens" for detonation, it's simply too hard to hear detonation at higher rpms because of all the other noises, so at that point and at WOT you are at the mercy of the tuner as to what they think will work best. Hopefully at that point they have a good A/F meter and EGT measuring things to properly set the maps for best - safe - power.

At WOT and at open loop operation the ECU is going to follow a predetermined "path" or set of numbers, but these will be modified by other parameters. So if the tuner does not take the time to test with other instruments or doesnt know all the "mods" they could put in a number like 10 for advance, but really end up with 15 because the program has added other things, can be scary.

I'm basing my knowledge on the Nissan ECCS system of about 3 years ago. But tuning is tuning.

Ferris TMK

Perhaps this is why MTM is a little less aggresive higher up..

VonK :: Retired

.... how is it that the ECU responds to higher Octane gasoline (up to a point) if it doesn't test for detonation at all revs. I think the detonation sensors would have a very narrow band width to isolate the ping frequency that is much higher than the mechanical engine noise.

In general, what you're saying is that the ECU sets ignition advance (among other parameters) according to several interactive multidimensional maps that are initially fixed from the factory, and then the "chippor" modifies one or more of the map profiles to higher limits (RPM, boost, fuel delivery, ignition, EGT etc.). Boy, to do this right without an engine dyno and lots of testing must take some really keen intuition. I understand, the MTM chips were developed on an engine dyno in Germany. I wonder who else did that. Or do others just copy the MTM maps and then go from there? :-)

VonK :: Retired

Precisely!

frank

MTM is not a large a company nor is it as widely popular in europe as I used to think

VonK :: Retired

I understand the MTM development guru came straight out of Audi.

frank

Meyer worked on the 5 cyl turbo's before he left and started MTM around 1990

also from what I've been able to determine, Peter Link is the one who does all the day-to-day

software tuning, and Hr. Meyer handles the overall direction of the company


so it seems they tune cars the same way as the rest of the tuners..

Dyno's and test gear and lot's of R&D

VonK :: Retired

MTM gives me a warmer feeling for having been done right. I'm still trying to decided which to get.

frank

MTM and ABT...


C.E.C is still a year away from marketing the Oettinger 1.8T chip (with a CA EO number at least)


and has ZERO plans to sell the Oettinger S4 chip