034 EFI, controlling ignition with Haltech IG5?

[Orin Eman]

>
> I have heard that Audi ignitions are some of the best, and most OE systems
> can produce enough spark energy for more than double the stock power.
> However, I've heard from listers and others, timing is very critical, and in
> most cases that go above and beyond mild upgrades, the pre dual-sensor
> sensor systems aren't good enough. What do you say about this argument? Is
> it really dual vs. single, or is it a better system? I have seen most
> systems, even race types [such as Electromotive], use only one sensor.

The dual knock sensor system is better - the knock sensor code in the
dual sensor ECU (MAC14 on) is more sophisticated than that in the
single sensor ECUs.  On top of that, I believe that one sensor is
marginal for a bank of more than 4 cylinders.

> Would you recommend switching to an ECU w/o knock sensing at all? What about
> on the higher compression engines, like the KH or modified MC? How much
> power do you think may be gained by pushing the timing past the norm for a
> turbo and letting a knock sensor retard to a safe level? What do you think
> the real purpose of the knock system was designed to be?

It's a bad idea on the earlier engines to advance the timing and let
the knock sensor take care of it.  The minimum retard is nearly 3
degrees and is very noticeable.  The car will feel much smoother if
the knock sensor isn't triggered.  The knock sensor seems to be more
of a save the engine from bad fuel while allowing best possible
performance with good fuel feature than a best performance all the
time feature.

It's best to set the timing table for the maximum advance that doesn't
trigger the knock sensor.

> About ignition only ECU's, the J&S seems to be the most advanced in terms of
> knock control. It's compat. w/ 5-cylinders and can use various input
> sensors, such as MAP, crank, or dist., etc.Also this brings you to Bosch's
> modern day level w/ individual cylinder knock sensing. Here's the link:
> http://www.safeguard.20m.com/index.html

It would be interesting to see how well this detects knock compared to
a MAC11 or MAC14... we have wired up these (and added some code)
to flash a light when knock is detected.  They can both detect knock
_well_ before it is audible and I'd want any other product to do the
same.  By the time you can hear knock under boost, damage is already
being done.

Orin.