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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, 11:35 AM   #11
t h i c c
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Default Re: Mods for a S M O O T H ride: brands/quality?

Quote:
Originally Posted by jlewis92683 View Post
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
It's possible this is the issue I'm facing. The previous owners of the car might have stomped on the clutch a little hard or driven it like maniacs. Maybe the firewall is a bit munted.


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Originally Posted by Achill View Post
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
I had it retuned by my local subaru guys at one point, it helped quite a bit. I'm not sure if I wanna do a performance tune, I'm pretty happy with the stock power, and I don't want to increase the wear and tear. I think the majority of my bogging issues are the clutch being inconsistent.

Sometimes the biting point is right in the middle and the car drives perfectly, I can clutch up to the biting point, add revs as I ease it through and then continue to add revs as I release the clutch, and it's very smooth, other times I bring the clutch to the same point, add revs, and as I release the clutch and I'll feel the transmission get a small jolt and bog a little, because the biting point was suddenly way higher, and I didn't give it the time it needed to get to the right speed. I've since learned to baby the clutch ALL the time, but after driving some of my friends cars around (s2000, evo 8, s15 etc.) I kinda just want the clutch to act normal and stay normal.


Would all my clutch troubles go away if I just replaced it with a stage 2/3 and lowered the pedal height? I was told by a subaru guy that sometimes the clutch changes engagement height due to the nature of the hydraulics.

Last edited by t h i c c; 07-12-19 at 11:45 AM.
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Old 07-12-19, 03:54 PM   #12
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Default Re: Mods for a S M O O T H ride: brands/quality?

OP I think you’re on the right track. And I have to disagree with those that said Grp.N mounts will increase NVH. I just got GrpN motor and tranny mounts, pitch stop, and tranny bushings done a week ago and I don’t notice any increased NVH at all. In my old GD I did feel some NVH making that switch, but the extra chassis rigidity VAs already have make any increased NVH unnoticeable.

I also got motylgear put in the tranny and shifting is super smooth. With that new oil and GrpN mounts, it’s really way more smooth than stock. Shifts are more precise, smooth, with way less shifter play and jerkiness when letting the clutch go. And power transfer is smoother since it doesnt have to rock the engine/tranny before power gets the wheels moving and it has less rebounding happening too.

Now if you’re looking at full metal mounts, I’m pretty sure those will have noticeable NVH.
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Old 07-12-19, 04:45 PM   #13
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Default Re: Mods for a S M O O T H ride: brands/quality?

you can do everything you want, but these cars will never be super smooth.

Driveshaft does help but still bad between 1-2800k
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Old 07-12-19, 05:44 PM   #14
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Default Re: Mods for a S M O O T H ride: brands/quality?

Strange how the clutch is described as inconsistent.

Maybe need to check if there's bubble inside the clutch fluid line?

Braided clutch line is also available and that is a good way to keep things feels more consistent.

STI jerks at low speed, but at high speed this is one very smooth car to drive fast.
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Old 07-12-19, 05:51 PM   #15
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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 jaswrx View Post
you can do everything you want, but these cars will never be super smooth.

Driveshaft does help but still bad between 1-2800k
True, but smoother is possible.
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Old 07-12-19, 06:37 PM   #16
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Default Re: Mods for a S M O O T H ride: brands/quality?

Quote:
Originally Posted by jaswrx View Post
you can do everything you want, but these cars will never be super smooth.
Yup,

Quote:
Originally Posted by jaswrx View Post
Driveshaft does help
Yup,


Quote:
Originally Posted by jaswrx View Post
but still bad between 1-2800k
??? what does this mean?
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Last edited by mheyman; 07-12-19 at 06:43 PM.
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Old 07-12-19, 07:33 PM   #17
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Default Re: Mods for a S M O O T H ride: brands/quality?

the driveshaft helped in the 2800-4500 rpm, but I didn't notice that much difference in the lower rpm regarding smoothness.

I further added Group N Tranny and Engine Mounts and sill the same, so...

It is what it is. I feel it's the worse when you let off the gas...
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Old 07-12-19, 09:18 PM   #18
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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 drummerboy View Post
OP I think you’re on the right track. And I have to disagree with those that said Grp.N mounts will increase NVH. I just got GrpN motor and tranny mounts, pitch stop, and tranny bushings done a week ago and I don’t notice any increased NVH at all. In my old GD I did feel some NVH making that switch, but the extra chassis rigidity VAs already have make any increased NVH unnoticeable.

I also got motylgear put in the tranny and shifting is super smooth. With that new oil and GrpN mounts, it’s really way more smooth than stock. Shifts are more precise, smooth, with way less shifter play and jerkiness when letting the clutch go. And power transfer is smoother since it doesnt have to rock the engine/tranny before power gets the wheels moving and it has less rebounding happening too.

Now if you’re looking at full metal mounts, I’m pretty sure those will have noticeable NVH.
Good to hear, I figured the group N stuff wouldn't be too bad since it uses rubber as well, just not as soft as stock.

Quote:
Originally Posted by jaswrx View Post
you can do everything you want, but these cars will never be super smooth.

Driveshaft does help but still bad between 1-2800k
That's ok, I know it's a rally car, but I want the jerkiness to be a result of my own poor driving and take away the external factors.

Quote:
Originally Posted by dlheman View Post
Strange how the clutch is described as inconsistent.

Maybe need to check if there's bubble inside the clutch fluid line?

Braided clutch line is also available and that is a good way to keep things feels more consistent.

STI jerks at low speed, but at high speed this is one very smooth car to drive fast.
That's a really good idea. Frankly everything will be a million times better if the clutch just stays at the same spot.
I find when the car is cold (Australia cold, so like 8-14 degrees C) and on a flat surface the clutch is quite consistent for a while, but after driving for a while and parking, the clutch engagement height seems to change. It could be a bubble.

Quote:
Originally Posted by jaswrx View Post
the driveshaft helped in the 2800-4500 rpm, but I didn't notice that much difference in the lower rpm regarding smoothness.

I further added Group N Tranny and Engine Mounts and sill the same, so...

It is what it is. I feel it's the worse when you let off the gas...
I thought the pitch stop mount was the important one for early smoothness. Either way, I'll be happy if I can shift a little easier.
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Old 07-13-19, 03:17 AM   #19
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Default Re: Mods for a S M O O T H ride: brands/quality?

Quote:
Originally Posted by t h i c c View Post
Good to hear, I figured the group N stuff wouldn't be too bad since it uses rubber as well,
Most all offer rubber isolated mounts, Cusco, Torque Solution, Perrin, Beatrush . . . and in every case if you can feel the difference in stiffness, you can feel it in NVH.


Quote:
Originally Posted by t h i c c View Post
That's ok, I know it's a rally car,
Why I'm writing. No, its a sporty family car.


Quote:
Originally Posted by t h i c c View Post
everything will be a million times better if the clutch just stays at the same spot.
Eliminate the clutch delay valve. Already suggested and not that difficult - and there is no downside except possibly warranty. Not likely to be noticed if If you are gentle with your tools.


Quote:
Originally Posted by t h i c c View Post
I thought the pitch stop mount was the important one for early smoothness. Either way, I'll be happy if I can shift a little easier.
Stiffer mounts will create NVH. N and V come with H.

ADDED: This is simple physics - people can claim otherwise if they like.
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Last edited by mheyman; 07-14-19 at 06:15 AM.
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Old 07-13-19, 11:26 AM   #20
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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 mheyman View Post
Most all offer rubber isolated mounts, Cusco, Torque Solution, Perrin, Beatrush . . . and in every case if you can feel the difference in stiffness, you can feel it in NVH.
All those use either polyeurethane and/or much much less rubber than the OE design which is why they have noticeable NVH. They’re definitely harder than group N because of it. Now with group n you can feel the rubber is stiffer than stock, but on the VAs it doesn’t affect NVH like it did on the GD.
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