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Discussion Starter · #1 ·
I never noticed this when I test drove my car....But when you're upshifting between gears (especially 1st going to 2nd), the RPMs take forever to come down, im guessing due to a heavy flywheel?

The concern i have is that when im accelerating (even normal-brisk) when I want to shift from 1st into 2nd, I have to wait a few seconds for the RPMs to come down before it revmatches and I can bump it into 2nd. Otherwise, If i shift into 2nd then I get the jerk as the clutch forces the RPMs down....and leads to more clutch wear. Kinda makes it hard to accelerate quickly since im always waiting for the RPMs.

Anyone else experiencing this?

Also, where does your clutches grab? mine starts about halfway up and fully engages about 3/4 of the way up, was like this since the day I got it from the dealer. Test drove the Focus ST and it grabs right off the floor.
 

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I havent had that problem but my clutch grab 1/2starting to 3/4 fully engaged

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Mine does the same rev thing, but I always assumed it was an engine protection thing, or the like for break in. Mine doesn't jerk too badly going into second gear - as long as I'm shifting between 3000 and 3700 rpms. If I shift it lower, it's like I'm lugging the clutch into the band. If I shift it higher, it's full-tilt-boogie, "Hey it's playtime!" and the tires blip. Both of which lead to premature clutch wear.

As for the clutch take-up, ditto. I'll have to talk to my performance connection at the dealer when I get my 3k mile service.

Edit: Just as I expected, mostly when engine temps are cooler.
 

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I prefer the engagement up high as its less footwork while shifting, and yes the rpm does hang a bit but from what I understand its in the tune to help with shifting.
 

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I prefer the engagement up high as its less footwork while shifting, and yes the rpm does hang a bit but from what I understand its in the tune to help with shifting.
I agree with the shifting, it does allow a faster shift with less effort. As for the rpm hang, that's the thought I was trying to convey. I have something I'm going to try on the drive home. If I can confirm it, I'll post it.
 

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Discussion Starter · #7 ·
Thanks for the response guys. Glad to see I'm not the only one. Gotta get use to the drive.

I also like the engagement higher up, just driving the focus was completely different and wasn't sure why. Either way great car and really enjoy going back to a manual.
 

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Okay, just got home, and this is what I noticed:
When the car had not quite reached operating temp, the the 1-2 shift was as described in the OP.
As operating temp climbed, it started to fade.
At operating temp, engaged in a little more spirited shifting, the revs fell right into line with a more expected outcome.
After that, all was right, regardless of driving demeanor.
 

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It's a heavy flywheel. It picks up revs fine, but keeps them longer.

I believe this also has an effect on our torque output, but my understanding of flywheel science is a little shaky
 

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While we're on this subject, does anyone else notice the occasional clutch chatter?
 

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My guess is it's due to two factors - one is the weighty dual-mass flywheel. The other is for emissions purposes. Lots of modern cars have the same "issue". Rev-hang reduces the amount of unburned fuel that passes into the exhaust when you let off the throttle. The revs stay at the same level momentarily/slowly drop to burn the excess fuel. Like G-Man observed, it makes sense that this is more noticeable when the engine is warming up since it is running richer in that state. As the engine warms up, the ratio leans out (less excess fuel to burn off) and the rev hang effect dimishes.
 

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Also of note in this thread:
I turned off my Hill Start Assist after witnessing it in action. Not because I can do better, but I live in the flattest part of Florida. All it did was slow my driveway exit, as I just let it roll out. But before I shut HSA off, I observed the 3 second hold on the brakes.
On my drive home last night, while the engine was still warming to operating temp, when I would clutch-in (to coast rather than brake), it seemed to hold the revs for almost exactly 3 seconds. Maybe the code for the throttle servo is written the same as the brake release for HSA.

I encourage anyone to try this, it may be common across the platform.
 

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Hi ! New on this forum but not on others

the rpm hangs on like a rev match upshift for idiot proof manual transmission operation

once flashed with the cobb ap it goes away ;)
 

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Hi ! New on this forum but not on others

the rpm hangs on like a rev match upshift for idiot proof manual transmission operation

once flashed with the cobb ap it goes away ;)
Hmmm mine still lingers high before falling and I have been tuned for a while now...
Mine still hangs as well. It has nothing to do with the AP and everything to do with the dual mass flywheel.



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