OEM master cylinder won't work with Spec....
Thread Starter
Race Director
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From: N. Alabama
OEM master cylinder won't work with Spec....
I suppose I am one of the unlucky ones. My SPEC 2 will not disengage with the OEM master. No problem until the swap. New TICK on order ATTM. 
Tech Contributor
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Le Mans Master
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St. Jude Donor '03
Umm, yes.
Spec is notorious for needing slave shimming, so much so they include the shim with their clutch kits.
Not everyone will need it, but it's something that should be measured for at the time of installation, and used if need be.
If you don't measure, you don't know...Well, at least not until it's all reassembled and then write a post like the OP did.
Spec is notorious for needing slave shimming, so much so they include the shim with their clutch kits.
Not everyone will need it, but it's something that should be measured for at the time of installation, and used if need be.
If you don't measure, you don't know...Well, at least not until it's all reassembled and then write a post like the OP did.
Melting Slicks
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If your m/c is functioning properly replacing it will not solve your problem. If you were to install a new m/c with larger bore to try and extend the throwout bearing more it will blow the seals and damage the t/o. Could also damage the diaphram spring on your pressure plate. The shimming suggested above is what you probably need to do. In general, you want the t/o bearing to be about 1/8" away from the fingers of the diaphram. No more than that. A little less may ok depending on pressure plate. Check with the mfg. It's still a good idea to install the tilton m/c that tick sells as it is an improved raplacement, but will still require the shimming unless your current parts are not working as they should.
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From: N. Alabama
Called Spec and they said that even though the C5 did not generally need the shim, it sounded like I might need it in this case. However, going with the Tick solves the problem, reduces pedal pressure, and should be much better altogether. As far as new slave, they are included with Spec kits.
http://www.tick-performance.com/tick...te/hydraulics/
http://www.tick-performance.com/tick...te/hydraulics/
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Thread Starter
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From: N. Alabama
If your m/c is functioning properly replacing it will not solve your problem. If you were to install a new m/c with larger bore to try and extend the throwout bearing more it will blow the seals and damage the t/o. Could also damage the diaphram spring on your pressure plate. The shimming suggested above is what you probably need to do. In general, you want the t/o bearing to be about 1/8" away from the fingers of the diaphram. No more than that. A little less may ok depending on pressure plate. Check with the mfg. It's still a good idea to install the tilton m/c that tick sells as it is an improved raplacement, but will still require the shimming unless your current parts are not working as they should.
Burning Brakes
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From: Okinawa
haha you got another thing comin if you think the tick will reduce pedal pressure...i liked the way my spec clutch felt way better prior to the Tick master install...pedal pressure seemed to increase 40% or so
Thread Starter
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From: N. Alabama
Wow! That seems to be totally contradictory from the rules of hydraulics, other persons' experiences, and aftermarket manufacturers' recommendations. Are you fairly certain there is not another problem?
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St. Jude Donor '03
Trying to force a higher volume of fluid through a passage of unchanged volume will increase applied fluid pressure....which will never require less work on the input side.
A simple search of Tick master will tell you all you need to know about pedal pressure. Even Tick will tell you it gets a bit stiffer.
It has to, or their claims of higher volume would be false.
Thread Starter
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From: N. Alabama
You guys are correct! I had read some wrong information from another source. Reading TICK's FAQs says maybe 15% increase. I hope that is not a direct correlation to pedal feel with their SPEC2 and OEM master cylinder w/o shim. Because another 15% over current configuration (albeit inadequate) would get to be a little tiresome with shifts required on some of the road courses I have been running.
Thanks again for setting me straight on this.
Thanks again for setting me straight on this.
Thread Starter
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From: N. Alabama
I suppose I could get out my old fish weighing scale and rig it up to the harness bar, configure a series of pulleys to allow full pedal travel and try to quantify the exact percentage increase but then I would have to deal with that whole ratio thingy.....
Melting Slicks
Joined: Apr 2006
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If you match the bore size of the new m/c to the original your pedal effort will remain the same all else unchanged. Tilton makes a large variety of m/c. You could ask tick to supply you with smaller bore size if their standard one is larger than factory. I have yet to get an answer as to what bore size they use. The tilton m/c's have it cast into the side.
On the pfadt mounts, I have thier motor mounts and have not noticed any additional vibration.
On the pfadt mounts, I have thier motor mounts and have not noticed any additional vibration.
Pro
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