1.5T Rough clutch engagement

kluo

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Just noticed this a couple days after i installed my catless downpipe:
If i am starting from a complete stop and let the car accelerate and shift to second with the revs about 3500 - 4k rpm driving in a spirited manner, the car feels like it takes a while to catch on to catch second and feels like the car just downshifter while not rev matching so you get all the winding feel making the driver and passenger lunge foward.. the rest of the gears are fine. it only happens in first gear and not the other gears.
Does anyone else have this issue? Is my clutch slipping?
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crxFITcivicBOY

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shift to second with the revs about 3500 - 4k rpm driving in a spirited manner, the car feels like it takes a while to catch on to catch second and feels like the car just downshifter while not rev matching so you get all the winding feel making the driver and passenger lunge foward.. the rest of the gears are fine.
Can you give more information?
For example,

(1) You are shifting at 4kRPM in 1st. When are you letting off (reengaging the clutch?) for 2nd?

The RPM gaps are big between 1st and 2nd, and it naturally takes time for the revs to drop to get a smooth shift; this is especially true on these cars when riding out first gear.

You could be driving more “spirited” because of the cat less downpipe sound, and just shifting outside of your usual zone, causing jerky shifting. Just one possibility....
 
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kluo

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A buddy of mine has also mentioned that to me. but i don't think taht is necessarily the case.

So coming from a complete stop, i will clutch in shift to first and let off. once it gets going and i bring it up to about say 4k rpm, i will let off shift to second and let go. naturally i'd expect the car to drop around 3.5k rpm ish but it feels more like it boggs / engine braking and the rpms drop even more before i can continue going.

If i take it easy and shift around 4k it does drop to about 3.5k rpm and i am able to keep going smoothly
 

crxFITcivicBOY

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So the gap from 1st to 2nd at 4K RPM is a lot more than 500rpms. For example, shifting at 3k RPM in 1st, I’m actually expecting 2nd to be at 1750 RPM. So for 4K RPM in 1st, I’d clutch in, put in 2nd and let out the clutch for 2nd at 2.5k RPM (I’m saying these numbers from memory so I’ll confirm tomorrow while driving). When you shift at 4K and let the clutch out at 3.5k you have a big mismatch in speed between the engine and transmission. The only way for that to be smooth is to slip the clutch until the wheels get up to the engine speed OR you let up off the clutch fast and get a jerkiness as you decelerate the engine to the correct RPM. This explains the RPM drop you are seeing.

Hope this helps?
 
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kluo

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hmm, i'll give this a try tonight. that does make sense though.
 


LilToTo17

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Well if you don't have ktuner then your most likely experiencing rev hang and stock clutch and cmc can't bang gears or shift super quick
 

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One thing I discovered is that if you get off the clutch faster, the shift will be smoother from 1st to 2nd. The same applies for all other gears actually.

At first I was letting go of the clutch rather slowly, trying to feel the engagement and that caused some jerkiness. Then I tried letting go of the clutch as soon as I have shifted into the next gear and it felt a lot better. (of course you get back on the gas asap when letting off the clutch)

P.S. I have a short shifter cable adapter from Acuity so that might help with shifting speed a little as the throws are shorter.
 

LilToTo17

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One thing I discovered is that if you get off the clutch faster, the shift will be smoother from 1st to 2nd. The same applies for all other gears actually.

At first I was letting go of the clutch rather slowly, trying to feel the engagement and that caused some jerkiness. Then I tried letting go of the clutch as soon as I have shifted into the next gear and it felt a lot better. (of course you get back on the gas asap when letting off the clutch)

P.S. I have a short shifter cable adapter from Acuity so that might help with shifting speed a little as the throws are shorter.
Stock cmc isn’t good at pushing fluid through. With an upgraded cmc you can bang gears all you like. If you want no rev hang because of the stock dual mass flywheel then get an aftermarket single mass clutch/flywheel
 

250GTCalifornia

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One thing I discovered is that if you get off the clutch faster, the shift will be smoother from 1st to 2nd. The same applies for all other gears actually.

At first I was letting go of the clutch rather slowly, trying to feel the engagement and that caused some jerkiness. Then I tried letting go of the clutch as soon as I have shifted into the next gear and it felt a lot better. (of course you get back on the gas asap when letting off the clutch)

P.S. I have a short shifter cable adapter from Acuity so that might help with shifting speed a little as the throws are shorter.
So, you don't wait for the RPMs to drop? You immediately shift into gear after pushing in the clutch then let off? Almost like a no lift shift? I feel like that would be worse. It's a choice between riding the clutch for smooth engagement or bucking the car.

I'm going to try out crxFITcivicBOY's suggestion, but I wonder if going all the way down to 1750 is too far.. especially with cars behind me at a red light. Sometimes I have no choice, but to go to 4K so I don't keep up traffic.
 
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kluo

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One thing I discovered is that if you get off the clutch faster, the shift will be smoother from 1st to 2nd. The same applies for all other gears actually.

At first I was letting go of the clutch rather slowly, trying to feel the engagement and that caused some jerkiness. Then I tried letting go of the clutch as soon as I have shifted into the next gear and it felt a lot better. (of course you get back on the gas asap when letting off the clutch)

P.S. I have a short shifter cable adapter from Acuity so that might help with shifting speed a little as the throws are shorter.
This will definitely make the car feel like it's bogging. I've tried this and it didn't work for me.

I have a ktuner with the rev hang disabled.

@crxFITcivicBOY suggestion worked but damn. The revs fall super low. I might just drove slowly then from 1st to second. Or look into a aftermarket cmc like @LilToTo17 suggests
 


Tzfng

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So, you don't wait for the RPMs to drop? You immediately shift into gear after pushing in the clutch then let off? Almost like a no lift shift? I feel like that would be worse. It's a choice between riding the clutch for smooth engagement or bucking the car.

I'm going to try out crxFITcivicBOY's suggestion, but I wonder if going all the way down to 1750 is too far.. especially with cars behind me at a red light. Sometimes I have no choice, but to go to 4K so I don't keep up traffic.
What do you mean wait for the RPM to drop? What im talking about is just regular shifting but release of the clutch in a faster and smoother motion. I don't experience any bogging or jerkiness.
 
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kluo

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What do you mean wait for the RPM to drop? What im talking about is just regular shifting but release of the clutch in a faster and smoother motion. I don't experience any bogging or jerkiness.
What i'm experiencing is when i start the car from a stop in 1st gear, i'll climb up to 4k rpm in a faster way than usual or rather a "spirited" way and the car's rpm would drop significantly and be around say 2k rpm ish give or take. Now you're saying if i release the clutch in a faster and smoother motion... if i release the clutch faster the rpm would not have time to match the engine and would ultimately lead to a jerky motion as i am experiencing. Not sure if that made sense.
 

LilToTo17

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What i'm experiencing is when i start the car from a stop in 1st gear, i'll climb up to 4k rpm in a faster way than usual or rather a "spirited" way and the car's rpm would drop significantly and be around say 2k rpm ish give or take. Now you're saying if i release the clutch in a faster and smoother motion... if i release the clutch faster the rpm would not have time to match the engine and would ultimately lead to a jerky motion as i am experiencing. Not sure if that made sense.
Just curious but you know how to drive a manual right lol? These cars are literally the easiest manuals to drive. The only time you have a jerky motion is if you let off the clutch to quick and give it too much gas
 

250GTCalifornia

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What do you mean wait for the RPM to drop? What im talking about is just regular shifting but release of the clutch in a faster and smoother motion. I don't experience any bogging or jerkiness.
What you're describing is dumping the clutch which is not good.

When you're in 1st gear @ 4K RPM you don't want to shift into 2nd gear and release the clutch at 3750 RPM.
 
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kluo

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Just curious but you know how to drive a manual right lol? These cars are literally the easiest manuals to drive. The only time you have a jerky motion is if you let off the clutch to quick and give it too much gas
Yes lol I do know how to drive a manual. If I drive normally this doesn't happen. If I drive slowly / regularly I only see the rpm drop about 500-750 ish and catch right away. Accelerating quickly results in a higher rpm drop from about 4k to 2k rpm
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