X-Tau - getting started

teg · Post by **teg** » Tue Jun 27, 2006 6:53 am

Hi!

I have just started to use X-Tau, but I don't really don't know where I should start. Here I have 2 logs, log 1 with default (MS2 v2.6**) xtau table settings and second one has double size values (scaled with 2).

I don't really see any difference in logs.. neither one didn't work as expected.... Where should I start to tune, time table or puddle factor?

Bernard Fife · Post by **Bernard Fife** » Tue Jun 27, 2006 7:09 am

teg,

With X-Tau, leave the existing accel enrichments in place, and start by adjusting the X factor. If that doesn't help, try increasing the Tau time table entries in the areas where you are having troubles with lean spots (engine coughs on accel) (this is easier said than done, because by nature accel enrichment involves more then a few rpms! So raise whole blocks of Tau values at a time.).

The Tau time table is deliberately conservative, so in most cases it will require increasing, by perhaps 50% to 100%.

As you get dialled in, you can start reducing the 'normal' accel enrichments. (Note that you may have to increase the cold accel multiplier as you do this.)

I will attach my Tau table - my X is 25%.

There's more here: http://www.megamanual.com/ms2/xtau.htm

Lance.

teg · Post by **teg** » Wed Jun 28, 2006 11:27 pm

Hmm.. I get lean and rich spikes when accelerating deaccelerating. Do I have too big X or is the problem in Tau?

whittlebeast · Post by **whittlebeast** » Thu Jun 29, 2006 2:49 am

You appear to have an RPM issue that is driving the Xtau nuts. You have to smooth out the rpm first.

AW

teg · Post by **teg** » Fri Jun 30, 2006 1:23 am

I decreased lag factor of rpm and got it littlebit more stable. I'm reading rpm from coil, so probably I can't get it better.

But back to the point:
- Is those spikes caused by too small X?
- is too long/short time of tau causing AFR to remain lean/rich for too long time?