munis

Hey guys, asking for a friend. Can anyone tell me if there is way to get downpipes for these cars without getting a tune? Like may be by using a O2 Simulator? I know the first O2 sensor before the cat is used for the closed loop calculation for fueling. Its the O2 sensor which is placed downstream of the cat which is the problem. What I am wondering is, how much does the primary O2 sensor depend on the secondary O2 to sensor to make corrections for this car? So if I you were to use an adapter/ o2 simulator, would it throw of the readings significantly off for the ECU to start acting weird?

Also this is just for my own personal knowledge. When a tuner "tunes the car for downpipes" for example, what exactly are they doing? What do they mean by tuning for downpipes? Does this mean just shutting of the secondary o2 sensors? Or do they manipulate the boost curve, fuel and timing as well? What happens, if a tuner just shuts of the secondary o2 sensors, but do not change or touch any of the primary tuning parameters, i.e boost, fuel and timing. Will the car loose horsepower?

Thanks in advance!

raudiace4

They turn off the O2 sensors. And no you don't need tune for catless DPs, if you don't mind looking at a CEL on your dash the whole time. No you can't get rid of that CEL without a proper tune, and O2 spacers without a tune will not help.

jkob5

from my discussion with tuners, the downpipes will allow the turbos to make more boost and quicker so the ecu isn't expecting this and will pull power. I have yet to see someone put downpipes on without a tune, though, to confirm this. But it makes sense.

Andre Baracat

Alex98

I have no tune and catless downpipes and no CEL

skim7x

but using spacers ?

Gts-killer

What Spacers your using ? ive used fabspeed fancy spacers with catalyst and still the CEL came on.

https://www.fabspeed.com/universal-o...verter-single/

raudiace4

Full catless downpipes, on stock tune and no CEL with just spacers? Lol I need to see that to believe it.

munis

Hey man, mind linking your O2 sensors here if you do not mind? Also did you notice the car pull power in anyway?

Alex98

Plenty of videos on my instagram with no CEL 1slowc63

Andre Baracat

shardul

iTrader: (1)

This is good to hear that O2 non fouler, extender etc are working on the W205. On most cars they don't work.

skim7x

A buddy of mine just tried DP's with the fabspeed spacers and still getting CEL... how are you guys avoiding the CEL with DP's and no tune? Using a different spacer? Could you post a picture of your spacer so we could see the difference between it and the fabspeed? Thx!!

raudiace4

I also want to see pics, because i've never seen a car not throw CEL on stock tune with catless DPs. Spacer or no spacer.

Alex98

plenty of videos on my instagram with no CEL @1slowc63

Andre Baracat

skim7x

Haha dude.. yes yes we get it, go to your instragram. How about you actually provide some helpful information. What's your setup? O2 spacers or no? I swear to God if you say you have plenty of videos on your instagram again I'm gonna snap.

Alex98

Andre and I are running the same exact setup, There's a little kit that I'm selling that I know works. I just used 2 washers on each spacer I can get you the exact size but without the exact spacer I can't gurantee that it'll work. If you want you can PM about it. I'll have to try to find some pictures

p.s. go check out my instagram for some videos

skim7x

Hahaha... Touche... PM sent

Andre Baracat

zeedio

could you guys provide some more detailed information on what 02 spacers and such you guys are running?

zeedio

I going to do the catless downpipe install very soon, have you guys figure out if it works with 02 spacers or as told in the thread washers + spacer?

if so which spacers are being used? spacers on both upper and lower sensors, or just bottom sensors? what degree on sensors 45, 90? spacers with catalytic adapter???

thanks in advance