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Mods for a S M O O T H ride: brands/quality?
Mods for a S M O O T H ride: brands/quality?
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Old 07-12-19, 06:10 AM   #1
t h i c c
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Cool Mods for a S M O O T H ride: brands/quality?

Hi guys, I wanna make my stock 2015 STi premium run S M O O T H, I've driven it a bit over a year and I'm finding certain aspects of the car annoying. Shifter feel, engine bucking in stop/starts (I feel it in 2nd too, if I'm slowly accelerating for the comfort of a passenger, and hit a bump, the engine pulls hard immediately after I back off the throttle), and wandering clutch engagement.

From my googling and browsing the forums, I've come up with a to-do list of mods for my STi. I just wanna know if I'm on the right track with the brands/quality.
  • Cobb double-adjustable Short Shifter + bushings
  • Group N Transmission Mount
  • Cobb/Torque Solutions Pitch Stop Mount
  • Group N Engine Mount? Not entirely decided on whether I need it or not.

Could I also get some suggestions on what to do with the clutch? The OEM clutch doesn't feel too bad, but sometimes it bites ridiculously high (a mere cm from full release) and other times it's right in the middle, I can keep the shifts as smooth as butter if I pretend I'm doing a lazy Sunday drive, but I don't always have to time to baby the clutch and guess where it feels like engaging... e.g. darting across a main road quickly and accidentally dunking my revs into the ground because it's suddenly decided to engage right at the very top (This situation is kinda rare, but sometimes the clutch just radically changes on me and I get it wrong.)

Last edited by t h i c c; 07-12-19 at 06:13 AM.
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Old 07-12-19, 09:23 AM   #2
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Default Re: Mods for a S M O O T H ride: brands/quality?

A carbon fiber driveshaft will help with a lot of the jerkiness from a stop. Group N transmission and engine mounts firm up the driveline but they increase NVH, not make it smoother. I installed something as simple as urethane exhaust hangars last week and it made the car feel harsher.

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Old 07-12-19, 10:01 AM   #3
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Default Re: Mods for a S M O O T H ride: brands/quality?

^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

I liked, but the above needs reinforcement. Pretty much nothing geared toward performance will make to your car smoother except the eliminating any stumble if you experience it, and a CFDS.
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Old 07-12-19, 10:13 AM   #4
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Talking Re: Mods for a S M O O T H ride: brands/quality?

Quote:
Originally Posted by xrdriver View Post
A carbon fiber driveshaft will help with a lot of the jerkiness from a stop. Group N transmission and engine mounts firm up the driveline but they increase NVH, not make it smoother. I installed something as simple as urethane exhaust hangars last week and it made the car feel harsher.
Ah, I see, thanks.
So I'm better off with the carbon fibre driveshaft over the transmission/engine mounts for ride quality improvements. I'm not a huge fan of NVH, but I was prepared to get a little more of it from the bushings and short shifter. How about the pitch stop mount?

Quote:
Originally Posted by mheyman View Post
^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^

I liked, but the above needs reinforcement. Pretty much nothing geared toward performance will make to your car smoother except the eliminating any stumble if you experience i, and a CFDS.
Thanks.
What do you mean by reinforcing the driveshaft(also CFDS)?

Last edited by t h i c c; 07-12-19 at 10:26 AM.
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Old 07-12-19, 10:17 AM   #5
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Default Re: Mods for a S M O O T H ride: brands/quality?

Carbon fiber driveshaft will help with the bucking. I love my group N transmission mount as it makes the shifter feel amazing and prevents it from moving around under acceleration. It does increase NVH though so I'm not sure what your definition of smooth is. As for the wandering clutch engagement, I believe this is due to the clutch delay valve. I think in our cars it is built into the master cylinder and is tough to remove but I haven't really gone down that path yet.
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Old 07-12-19, 10:27 AM   #6
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Default Re: Mods for a S M O O T H ride: brands/quality?

Our Firewalls flex like crazy and I was having to deal with inconsistent clutch feel similar to what you are describing. After installing a clutch master cylinder brace. engagment was much more smother and consistent
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Old 07-12-19, 10:39 AM   #7
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Default Re: Mods for a S M O O T H ride: brands/quality?

Quote:
Originally Posted by VA STI View Post
Carbon fiber driveshaft will help with the bucking. I love my group N transmission mount as it makes the shifter feel amazing and prevents it from moving around under acceleration. It does increase NVH though so I'm not sure what your definition of smooth is. As for the wandering clutch engagement, I believe this is due to the clutch delay valve. I think in our cars it is built into the master cylinder and is tough to remove but I haven't really gone down that path yet.
My shifter doesn't really move around too much, but I struggle with stop starts occasionally due to a rotator cuff injury (RHD; 1st and 2nd can be a bit of a literal pain when the gearbox decides it's gunna be overly stiff and notchy, it's like shifting a truck sometimes). My hope is that I can make the gearbox feel more effortless, being able to flick from gear to gear with 2 fingers instead having to drive them in. Every now and then I can't even put the car into 3rd without double clutching, and this is just driving at normal speed.

As for the clutch, I did see some stuff on the clutch delay valve causing issues, but people have also suggested a clutch stopper mod. I'm not sure which way to go on this.
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Old 07-12-19, 10:43 AM   #8
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Default Re: Mods for a S M O O T H ride: brands/quality?

Honestly, you need a different car. You are going to spend thousands of dollars you'll never get back for minimal improvement while there are other cars which will meet your needs much better.
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Old 07-12-19, 10:56 AM   #9
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Default Re: Mods for a S M O O T H ride: brands/quality?

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Originally Posted by 8cd03gro View Post
Honestly, you need a different car. You are going to spend thousands of dollars you'll never get back for minimal improvement while there are other cars which will meet your needs much better.
Oof.
I had a think about my epic rant and took a drive around, to be honest I was being a little sensitive. The transmission isn't as bad as I make it out to be, and when the clutch is behaving itself I'm damn good at shifting, I feel I'm painting a masterpiece with my feet. I just need to clutch to stay consistent, and maybe smooth out the notchiness of the gearbox.
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Old 07-12-19, 10:58 AM   #10
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Default Re: Mods for a S M O O T H ride: brands/quality?

what about a tune for your car? your tuner should tune the bogging out by making it richer/leaner at light throttle


keep everything stock except anything fails... try Tyres with a soft sidewall, and or a higher sidewall. like 17s instead of 18s
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