jmartpr

Well.....that's kind of hard to answer. The obvious situation could be a lean situation of the engine but the ECU adapts and you also have knock sensors so very remote doing damage to the engine by running these. You do risk having a few CELs so a Tune (via a solution like COBB AP) or DMS solution is a must if going this way. IMO...if I was going to go catless I would definitely do a Tune in order to extract the most and keep things on the safe side.

jmartpr

With the COBB AP (which is what DMS uses) you can uninstall the whole thing and get the ECU back to stock in minutes for dealer visits...then when you get the car back you can install and upload the Tune again.

Mech33

If Porsche wants to see if the ECU was ever tuned, I'm sure they can tell.

Alan C.

That is true. Also, I'm sure Dundon ran fuel curves on their dyno.

Macca

The ECU shows how many time it's been written over in the counter.

It's simple with the race headers. Anything like a catastrophic engine or gearbox failure get the home mechanic around the corner to rock up and out the factory headers back on before you trailer it to the dealer!

jmartpr

That's true but at the dealer level you should be OK as that's what I do, actually recommended by the dealer.....would be great if someone from COBB or a dealer could chime in on this so we have the info from the source

gac1077

This's it's the best option.

gac1077

If you have a catastrophic engine failure removing the tune won't help the ECU it's the first thing Porsche will check and your warranty will be deny, I speak from experience, I'm sticking to just race headers until warranty it's gone.

ajag

Can you elaborate on the experience you had please?

Jamie@dundonmotorsports

Porsche has been good with exhaust parts and most dealers are even willing to install.

Tunes are a completely different conversation.

Some of the Cobb AP's for porsche go through a back door and don't set a write counter.

The 981 Cobb AP isn't setup that way and sets a write counter, so the car would show that there has been a software flash on the ecu (both for modified and back to stock).

Cobb is working on a firmware enhancement to no trip a write counter, but no timeline has been provided.

Jamie@dundonmotorsports

The SDI9 is closed loop fueling at all loads and rpms. After driving the car it will adapt to the new fueling requirements. The tune helps to resolve these further, but the car does a decent job on it's own...

sunnyr

But there is also risk with running aftermarket headers with cats - read about cats disintegrating and getting sucked back into the engine destroying it - link. Sure, can happen with stock cats, but guess warranty will cover that, but aftermarket ones, doubt Porsche will cover that.

Jamie@dundonmotorsports

Yes that's why high quality metal cats are critical in an aftermarket application. Cheaper ceramic core cats are typically the ones that crack apart...

CAlexio

seems like the market has settled on hjc? cats.. it's what fabspeed, cargrafics use. hope to avoid issues of that nature.

John@Fabspeed

HJS actually, tri-metallic cores straight from Germany