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Unitronic Stage 2 overrun file - worth it?
- Thread starter marc5800
- Start date
Mynameismyles657
New member
- Location
- Charlotte, NC
Is this available on a stage 1 tune, or only stage 2 like APR's?
bluekid99
Drag Race Newbie
- Location
- Pennsylvania
i flashed to the crackle part for apr on my is38...i dont really mind it...i dont run sport mode all that much so the occasional crackle and what not when free revving does make me smile a little...i wouldnt suggest it if you drive in sport mode constantly
Sorry to bring back this thread to life
But the following question is driving me nuts:
If the overrun / crack & pop feature is "hard" on the catalytic converter...
How are other manufacturers able to run this "overrun / crack & pop " feature while still having the OEM cat?
(Without it affecting the cat longevity)
But the following question is driving me nuts:
If the overrun / crack & pop feature is "hard" on the catalytic converter...
How are other manufacturers able to run this "overrun / crack & pop " feature while still having the OEM cat?
(Without it affecting the cat longevity)
I think with John's post, and a little better understanding of what is actually being done to create these crackles it's a non-issue.
From John @Uni's post:
"For reference, we're using the OEM strategy, which is active directly from VW/Audi by default in EU models. The function will automatically turn off if/when the hardware component protection limiters ("fail safes") that are incorporated into function are reached, for added protection."
I take that to mean "when the catalyst is hot, the car is hot, (all safety flags are green) the ECU shoots a bit of fuel (very high pressure, DI mist) into the cylinders which aids in cylinder cooling. This fuel can ignite or combust which creates an audible noise at the tailpipe".
This is not a 2-stage like system with a fuel injector shooting against the turbine, this is not "raw fuel" flooding a cylinder or soaking a cold catalyst. It's not the devil. It may be a love it or hate it thing considering peoples preferences, and some tuning companies might have released half baked tunes with unrelated issues, but having "pops and crackles" or whatever in a tune isn't inherently bad or problematic.
Also a lot of questions about the "OEM Cat" but these are all Stage 2 tunes with the feature added, so you should either have no cat or a metal cat that would be no issue. For the OEMs, they either use very expensive cats or don't have the same emissions warranty standards as we do in the US (as this is more prominent in EU region cars), or the noises are tuned from other directions.
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When you say "all safety are green", I don’t quite understand this. From everyone that i’ve talked to (including myself), you can literally turn the car on (cold) and start revving it and its going to pop and crackle...
True this is essentially the car dumping a bit of fuel after the throttle is released to burn in the exhaust to create this sound.
I’m not saying "it’s the devil" or bad to have this function but I keep hearing that its hard on the cat...
You do bring up a good point - this is only available on a stage 2 setup which requires an upgraded downpipe (no cat or metal cat), however isn’t OEM cats generally already metal / ceramic ?
I simply still don’t understand how this can be "hard" on the cat for a stage 2 setup (GTI or R) if all other car manufacturers are doing the same or are doing a very similar approach on OEM exhaust setups
You don’t hear Mercedes-Benz AMG division saying : "pops and crackles in Sport / Race mode can cause damage or wear on OEM exhaust"...
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madelinot
Ready to race!
- Location
- Ottawa, ON
I did the *upgrade* to the "Pops and crackles" tune. Noticeable, but not loud at all...
Jaguar XK's are a good example. Probably has the loudest in the world.
Ya it’s not bad.
Unless you downshift it to 4000 rpm. Then it’s obnoxious!
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Anybody know this person by any chance? I love the sound of his gti. Just don't know the mods.
https://youtu.be/Z7xzI7auUUY
https://youtu.be/Z7xzI7auUUY
mightyandrew
New member
- Location
- HK
when this overrun feature will be available for ROW MK7 GTI?
John@Unitronic
Go Kart Champion
- Location
- Montreal
It's enabled for some of the ROW GTI's. Get in touch with your Authorized Dealer and ask!
mightyandrew
New member
- Location
- HK
I’ve email ur support got an reply which is only available for stage 2+ for overrun is that true? So stage 2 overrun not supported for my car?
John@Unitronic
Go Kart Champion
- Location
- Montreal
Unfortunately I am unable to tell you if it's true or not, as I don't have any information about you or your vehicle. If our Support provided you with that answer, then it's likely true.