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Discussion Starter · #1 ·
So Ive noticed that when accelerating hard, as I'm progressing through the gears, that when I throw the clutch in, I see a spike in the rpms in between the gears. I have eliminated the possibility that my foot is still slightly on the pedal giving a little bit of gas as I am pushing the clutch in buy letting off the gas before I even move the clutch and I still see this happen.
So my question is what is causing that? A lag in throttle response? or is there something in the tuning that spikes the rpms a bit to help with rev matching?
 

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Maybe somebody with a better understanding of the stock tune could chime in but i would guess its the combo of stock tune with the bov? The tuners on here would most likely be able to tune that issue out.
 

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My understanding is that this is some sort of environmental measure for euro emissions standards. The hanging revs/ blip is used to maintain positive crankcase pressure and reduce emissions.

If I am correct this is rectified with a tune (tuner dependant).

Im no expert but this is what my mechanic explained to me.

Your Stratified Tune may need to be expedited....LOL.
 

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I noticed the same thing after I installed my catback. Its not a big deal but tuning my car stopped it.
 

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Discussion Starter · #5 ·
Yeah, Im 100% ok with it, Im really just trying to understand why it is doing this.
Rev hang is a better term to describe this, I didnt know what to call it when making the post.
but I know that after I put on my exhaust, I started hearing it. It was probably there all along though.
 

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Isn't this textbook rev hang? Like when I was on my stock tune I always complained about the rev hang unless I was incorrectly diagnosing it.

My Stratified tune got rid of it.
 

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I actually like it. I had my tuner for my Fiesta ST increase the duration of the hang. I'll probably do the same thing for the Focus ST.

Sent from my SM-G935V using Tapatalk
 

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Exactly what the other few have suggested...rev hang. Does that from the factory, I swear I read somewhere it supposed to help make smoother shifts?. If/when you get an AP3 you can have your tuner turn that off. I found it to be counterintuitive and quite annoying.
 

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Noticed, also fixed with my stratified tune.
 

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Discussion Starter · #10 ·
Yeah, Rev Hang was the term I was looking for, at 10 pm I couldnt think of the correct term
 

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Exactly what the other few have suggested...rev hang. Does that from the factory, I swear I read somewhere it supposed to help make smoother shifts?. If/when you get an AP3 you can have your tuner turn that off. I found it to be counterintuitive and quite annoying.
When I would drive non-spirited but quicker than average shifts it would NOT be smoother because it would lurch forward. Which obviously led me to believe it was causing undue stress on my clutch. Not a fan, glad it's gone.

It's an epidemic typically only prominent in American cars or cars imported to America like the WRX. They are REALLY bad with it in some newer models.
 
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