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GT2 master/slave conversion

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Old 05-11-2017, 09:14 AM
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Bskyoon
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Default GT2 master/slave conversion

Finally got my car back after the conversion. About a month ago I had the power steering noises and found I had low/no pentosin in the reservoir and the clutch fluid was reservoir in the frunk was slightly over max. Typical signs of a slave failure. After topping off the ps the noise went away but came back a day later so I ordered the parts from EVOMS. There were a few hang ups w parts/installation but they were very good about overnighting things over to my shop and proving support. I would highly recommend them but most of you already know that. Anyway on to the good stuff:

I've read the clutch gets stiffer, that's a gross understatement in my opinion. It's most certainly ok for DD but the difference in feel is absolutely night and day, in a good way. I never realized this but the stock clutch felt more like a 90's 4 banger and this feels more like a 930. My only regret was I was trying to get my wife to learn manual and this will almost certainly kill any last inclination she had.

I'm curious, however, I never had a problem with the stock clutch or had any issues finding the 'engagement point' but for some reason with the conversion my shifts are a lot smoother. I don't have to try as hard to modulate throttle/clutch avoid that jerky motion between shifts. Anyone have insight into this? I'm positive its not a placebo effect, if anything my shifts would get worse from not driving...
Old 05-11-2017, 01:02 PM
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TypeRx
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Its not a placebo effect, removing the accumulator from the equation makes a big difference in feel. I too have the conversion and it massively improves feel (vs. stock 997TTs I've driven) but does also significantly increase pedal effort.

I don't DD my car.
Old 05-11-2017, 04:05 PM
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Bskyoon
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Actually, I'm still not exactly sure where the engagement point is which is why I'm confused. I'm just curious from a mechanical perspective as to why it seems to be much smoother with me being the independent variable, I didn't become a better driver in the last week.
Old 05-11-2017, 05:06 PM
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Glad to hear it worked out. The stock setup is so numb that you have to judge engagement by the position of your foot and what the tach/engine note is doing since there is no pedal feedback. Even then, if the slave or accumulator are acting up the position of the engagement point varies by engine RPM, temperature, and pedal position, so it's a moving target.

With the GT2 conversion, you can work the clutch engagement based on pedal effort and pedal feel, which I feel like is a better tactile system for controlling something precisely. It is stiffer which can be a bit of a pain in traffic or with a bad knee, but I also notice that you can feel when the clutch is fully disengaged which means you no longer have to go all the way to the floor when changing gears or coasting which is a bit easier than with the vague stock setup.

Sam
Old 05-11-2017, 05:30 PM
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El Dario Loco
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Are you running it with the stock turbo spring or is there a replacement spring in the kit? A lot of people switch to the gt3 spring for a lighter clutch with the gt2-conversion.
Old 05-18-2017, 09:04 AM
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Bskyoon
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Default Not sure...

You'd have to consult the guys at evoms on that, I just took the box to my shop and let them work it out. I can't imagine there was a spring involved that made the clutch lighter because if this is light then heavy would be a little too much..I think the stock clutch is rated at 35 pounds, this feels like 45-50.

I'm starting to understand now what everyone's saying about 'consistent' engagement point. After a bit more driving it does engage exactly the same place about an inch off the floor to full engagement at what seems like 3 inches then the rest feels like it is just travel. I never realized how inaccurate the stock clutch was because it was so livable and not really an issue.
Old 05-18-2017, 01:00 PM
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The EVOMS kit does come with a different clutch assist spring than the stock turbo one. I have driven my car (with the EVOMS GT2 conversion) without any clutch assist spring and it will be the highest clutch pedal effort you have ever felt in a car - guaranteed. Still driveable and great feel but a lot of force required for sure!

The GT3 clutch assist spring helps out tremendously with this.
Old 05-18-2017, 01:26 PM
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Yes, the kit does include a new assist spring.

Sam
Old 05-18-2017, 03:15 PM
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Originally Posted by TypeRx
The EVOMS kit does come with a different clutch assist spring than the stock turbo one. I have driven my car (with the EVOMS GT2 conversion) without any clutch assist spring and it will be the highest clutch pedal effort you have ever felt in a car - guaranteed. Still driveable and great feel but a lot of force required for sure!

The GT3 clutch assist spring helps out tremendously with this.
That's insane. I really can't fathom getting stiffer than this but I suppose we'd get used to it as with all things.
Old 05-18-2017, 03:19 PM
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LOL -- trust me, without the helper assist spring the car isn't fun to drive. It is doable, but feels like the clutch is from a 1970s jalopy.
Old 05-18-2017, 04:48 PM
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El Dario Loco
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Originally Posted by TypeRx
LOL -- trust me, without the helper assist spring the car isn't fun to drive. It is doable, but feels like the clutch is from a 1970s jalopy.
Old 05-19-2017, 04:38 AM
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Nate Tempest
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Just out of curiosity, why is it a GT3 spring with the GT2 slave? Wouldn't the GT2 spring be appropriate? (Or are they effectively the same, but the GT3 part is cheaper because it's not a GT2?)

Edit: I'm almost hoping my clutch will fail sometime soon so I can do this (along with a Sachs 2.5)!
Old 05-19-2017, 08:56 AM
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Originally Posted by Nate Tempest
Just out of curiosity, why is it a GT3 spring with the GT2 slave? Wouldn't the GT2 spring be appropriate? (Or are they effectively the same, but the GT3 part is cheaper because it's not a GT2?)

Edit: I'm almost hoping my clutch will fail sometime soon so I can do this (along with a Sachs 2.5)!
I was actually hoping IF this happened it would be around the time to replace my clutch so I could upgrade to the sachs. What don't you like about it?
Old 05-19-2017, 11:45 AM
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All of these changes to improve clutch feel/response has me thinking...

I've only had the car for a few months and around 1k miles, I don't drive it often, but I still don't think I have a good feel for the clutch, does this mean I am not alone with this experience? I've been driving manual cars for 10+ years, admittingly not in cars this powerful...

And forget some stop and go in sport mode, the throttle is so touchy and if you hit one little bump it either upsets throttle input or clutch engagement and I feel like I'm just learning to drive a manual.

Oh and the clutch accumulator was changed by the dealer prior to sale because of a stiff clutch, per the invoice, I never drove it before it was fixed.

Do others have the same experience and are these clutch changes to address some of these issues?
Old 05-19-2017, 12:27 PM
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El Dario Loco
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Originally Posted by theplings
All of these changes to improve clutch feel/response has me thinking... I've only had the car for a few months and around 1k miles, I don't drive it often, but I still don't think I have a good feel for the clutch, does this mean I am not alone with this experience? I've been driving manual cars for 10+ years, admittingly not in cars this powerful... And forget some stop and go in sport mode, the throttle is so touchy and if you hit one little bump it either upsets throttle input or clutch engagement and I feel like I'm just learning to drive a manual. Oh and the clutch accumulator was changed by the dealer prior to sale because of a stiff clutch, per the invoice, I never drove it before it was fixed. Do others have the same experience and are these clutch changes to address some of these issues?
I too have some problems with going from stand-still in sport mode. If I'm not really careful in balancing throttle and clutch I get this awkward jerky motion. I can't even imagine how it would be with an aggressive tune. Admittedly, I may not be a trained racing driver but I've been driving manual cars for 20+ years and have had the car for over 3 years. I'll probably do the GT2-slave conversion eventually but if I knew it would take care of this issue I'd do it like yesterday.


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