Decat Zorst......

[drb5]

I searched out details on decatting a t-sport a few day's ago and jaxx mentioned there was someone maybe trying to figure out how to mess with the ecu into thinking the lambda sensors, were in the right place, so the management light doesn't come on. Has this been sorted yet, so that you can easily fit a decat?

[SuperRetard]

Unless you fit a new ECU or fuel computer (a la S-AFC), then get it professionally set-up there's little point in a de-cat. The Yaris is too damn clever, as it senses the wrong o2 readings and drops into a hobbled 'get you home' mode... :(

[drb5]

The S-AFC was one mod i had in mind, but how would that mess with the ecu's reading of lambda? Just because it would be getting a higher air/fuel mixture?

[chrisb]

where do you get the decat from?

CB

[drb5]

Personnaly i would be using a rather local exhaust specialist. They can make up ANY exhaust system you want, between different bores and/or different back boxes. I used them for the scoob backbox, which i was MORE than happy with, so just a decat section, shouldn't be a problem. :D ;)

[SuperRetard]

The SAFC just fixes the fuelling on a certain map, which can be set up by you.

[drb5]

I know it does bud, but how will it help if i get the exhaust decatted, like you said it would, above?

[SuperRetard]

with a decat and no AFC, the ecu senses erroneous o2 readings, flicks on the check engine light, then goes down to a closed-loop on the fuelling. Normally it's retuning several dozen times a second, mine often changes by as much as 20-30% depending on the circumstances.

But on the closed-loop, it sits in what Toyota reckons is a safe run-anywhere, any-time map, which is more about getting you to the dealer than operating properly with your new exhaust.

That's what I know.

The next bit is what I'm hypothesising...

If you plumbed in the o2 sensors into decat, maybe the system would carry on open-loop tuning, pouring in more fuel to match your increased gas speeds. Or maybe it would think that your cat's buggered and drop to a closed-loop again. I dunno.

Or you could get an Air Fuel Computer from HKS or Apexi. I'm pretty sure these things will work over the top of your hobble mode fixed fuel map. So take it to a rolling road, set up the fuelling to take full advantage of your new zorst, then it don't matter that your ecu's just outputting the standard map, 'cos you've just re-written it to your own specs and you're getting the benefit of your new decat. I think!

[drb5]

Ker-ching! There's the money shot! :D ;)

Cheers bud, this thread will be getting saved and the safc will be purchased, if and when i get the little b*gger! :D