I'm over my SPEC super twin clutch
#1
Melting Slicks
Thread Starter
I'm over my SPEC super twin clutch
when i bought my car last feb, the guy before me had a spec super twin installed. great clamp pressure, will prob NEVER slip @ 550hp untill its completely toasted HOWEVER, its a complete PITA to drive around in and enjoy.
the engagement is less than 1/16 away from the end of the throw, its completely ON or OFF
its impossible to slip.
can it be driven, yes, im used to it but only tolerate it.
im at the point now that i would like to be able to let the wife, and other people (father, best friend) drive it without the worry about them killing the car 16 times. i dont think my father could even hold the clutch steady enough to try and drive it LOL
so i said all that to say this......spec super twin is coming out with only 2500 miles on it
what should i put back in that will hold end goal of 750-800 thats more user friendly
thanks in advance
yes i searched before i posted
the engagement is less than 1/16 away from the end of the throw, its completely ON or OFF
its impossible to slip.
can it be driven, yes, im used to it but only tolerate it.
im at the point now that i would like to be able to let the wife, and other people (father, best friend) drive it without the worry about them killing the car 16 times. i dont think my father could even hold the clutch steady enough to try and drive it LOL
so i said all that to say this......spec super twin is coming out with only 2500 miles on it
what should i put back in that will hold end goal of 750-800 thats more user friendly
thanks in advance
yes i searched before i posted
#2
Melting Slicks
I'd take a look at the Mantic-twin. I heard it has stock-like pedal feel, and can easily hold the power. That's the clutch I'll be going with soon.....like you, I'm done with this Spec-twin
Last edited by tlove32; 01-04-2016 at 07:40 PM.
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~STOLEN~ (01-04-2016)
#3
1/4 mile/AutoX
my stock clutch 99 is I think one of the easiest stick cars I have ever driven. you can almost just let the clutch out at idle !!!!
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~STOLEN~ (01-04-2016)
#4
Melting Slicks
Thread Starter
from what ive gathered the mantic and mcloud rxt are both great, guess at that point it would come down to price.
and this time im paying RPM to do the r&r......i have no interest in tearing that all apart in the garage again
the worst part about all of this is that i had the tranny and diff out in september for a lvl5 trans and lvl 2 diff with 410s.....and i elected to NOT change the damn clutch when it was apart cause i didnt want to spend anymore money so,
got the car out this weekend and stalled at a light cause i wasnt paying attention and i was like THATS IT!!!! im changing the damn clutch LOL
and this time im paying RPM to do the r&r......i have no interest in tearing that all apart in the garage again
the worst part about all of this is that i had the tranny and diff out in september for a lvl5 trans and lvl 2 diff with 410s.....and i elected to NOT change the damn clutch when it was apart cause i didnt want to spend anymore money so,
got the car out this weekend and stalled at a light cause i wasnt paying attention and i was like THATS IT!!!! im changing the damn clutch LOL
#5
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a stock clutch is not going to last long with 550rwhp and doesn't stand a chance to the op's goal of 750-800.. I would probably go with an rxt or mantic, I have an act twin disc rated for almost 1k ft/lbs of torque in my car and it has held and driven just fine for me... it is pretty firm but can be driven fairly easily... part of the reason mine is so firm is also due to the tick master cylinder, I installed one of those a few years back trying to solve an issue I had with the stock clutch... if you have an oem clutch master then the pedal won't be near as firm
Last edited by neutron82; 01-04-2016 at 08:47 PM.
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~STOLEN~ (01-04-2016)
#6
Melting Slicks
Thread Starter
Im glad you chimed in, I as well have a tick adj ms so that plays into it too
I was wondering about those act clutches , any benefit in your opinion from one brand to another, the only other clutch I've had experience with is RAM and it was in a hci 99 ss lol
Everyone suggests the rxt though.....this may be a sign
I was wondering about those act clutches , any benefit in your opinion from one brand to another, the only other clutch I've had experience with is RAM and it was in a hci 99 ss lol
Everyone suggests the rxt though.....this may be a sign
#7
1/4 mile/AutoX
a stock clutch is not going to last long with 550rwhp and doesn't stand a chance to the op's goal of 750-800.. I would probably go with an rxt or mantic, I have an act twin disc rated for almost 1k ft/lbs of torque in my car and it has held and driven just fine for me... it is pretty firm but can be driven fairly easily... part of the reason mine is so firm is also due to the tick master cylinder, I installed one of those a few years back trying to solve an issue I had with the stock clutch... if you have an oem clutch master then the pedal won't be near as firm
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~STOLEN~ (01-04-2016)
#8
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act makes a good clutch they just don't seem to be as popular in the domestic world... back in my import days that's all I would ever use and never had an issue with them so when I got the c5 I happened to find a really good deal on one and it sat there until I absolutely had to install it lol... I have a t2s-g01 if you want to look up the specific model... the tick will definitely add a bit of firmness to whatever clutch you decide to get but as long as you aren't a total puss cake you should be fine in my opinion
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#11
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#12
Melting Slicks
Thread Starter
Man I've read all sorts of horror stories about those damn shims, the act looks VERY nice out of the box
I have some time before I send the car to rpm so I'll be taking advice from and narrowing down. Hey maybe a vendor will have a clutch sale for me ( not likely ) lol
I have some time before I send the car to rpm so I'll be taking advice from and narrowing down. Hey maybe a vendor will have a clutch sale for me ( not likely ) lol
#13
Safety Car
no problem... there seems to be a lot of success with the rxt and mantic so keep your options open so you make the right choice for yourself... if you're doing the work it isn't particularly hard but it is a lot of work and I would be pissed if I went through it all and ended up not liking the clutch I just installed... I should also add that this one does not chatter at all, it is very quiet... it also comes balanced from act and did not require any shimming of the slave... those are some things that are often left out of the equation that you find out about during the install which sucks!... here's a few pics from when I was getting ready to put it in, it really is a nice piece
#14
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#15
Melting Slicks
Are you planning to run sticky drag tires? The answer would suggest material needed for the disc's.
Clutch & flywheel weight as well as pedal pressure are important factors with how easy the car is to drive & if a drivers meeting is required when someone other than the owner is operating the car
I'm just over 600rw & 500rt, my recent RST is working exactly as advertised....first time. I've tried the highly talked about LS7, RPS Twin Lite Carbon & the LT1 conversion.
Clutch & flywheel weight as well as pedal pressure are important factors with how easy the car is to drive & if a drivers meeting is required when someone other than the owner is operating the car
I'm just over 600rw & 500rt, my recent RST is working exactly as advertised....first time. I've tried the highly talked about LS7, RPS Twin Lite Carbon & the LT1 conversion.
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#17
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CI 6,7,8,9,11 Vet
St. Jude Donor '08
In 2008 I agonized over clutch selection for over a year. Price, reliability, feel, durability, ease of installation was of great concern.
SPEC Twin was $1300. back then!
SO,, Approx. 12 Forum Members got together and contacted SPEC and they did a GROUP PURCHASE us. If I remember correctly it was right around $1100.
Shortly after purchase, several of the Group Purchase guys had some serious SPEC Clutch installation & reliability issues. Slippage, warped disk, burnt up throw out bearings, sever vibration issues, etc..... Spec took care of the warped disk issues..
I thought I wasted my hard earned clutch money.
Here's what panned out and why some of those issues were encountered:
- The installation people failed to take the critical measurements needed for proper slave cylinder height and just installed the shim or didn't bother to install it at all.
The clutch would burn up very shortly after install OR not disengage and burn up the throw out bearing and or damage the synchros! -
- When the drive train was reinstalled into the bell housing (Trans/Differential & TT) all at once, the installers let the entire drivetrain weight rest inside the bell housing before the TT was fully inserted and bolted to the bell housing. That in turn bent the two disk hubs causing them to warp.
- Improper bleeding and improper TICK master cylinder adjustment was also another very common issue. Results in poor peddle engagement height, hard shifts or pressure plate damage.
-After fully understanding all of those issues and taking the proper steps to eliminate them, my SPEC Twin install went very well and it has been a really good clutch.
-Its not an ON/OFF engagement clutch. I have very good engagement and release height.
My wife on occasion has driven the car with out too much bitching. The TICK high volume Master makes the peddle much more stiff than if I would have used a normal volume Tick or an OEM master. At that time, only the high volume TICK was being offered.
I used great pains measure both critical measurements to determine shim size for the slave cylinder despite EVERYONES recommendation to JUST INSTALL the shim that came with the clutch. In my case, NO SHIM was needed for proper slave height. I remembered that I measured everything 4-5 times!
-I made a decision to break up the drive train into TWO parts. The transmission & differential as one install and the Torque tube as a separate install. Installing the TT into the new clutch is SO much easier and there is little if any chance of bending the disk hubs.
I went to great pains to not have issues with drive train harmonics/ vibrations. I had the SPEC Flywheel matched balanced to the old OEM ZO6 Fly wheel and installed the new flywheel in the same relationship back on the crank. NO VIBRATIONS.
I spent a good number of hours adjusting and readjusting the clutch peddle adjustment rod to get proper peddle height, correct clutch disengagement and engagement. I have a fairly big cam so, take off from a dead stop would sound like it could be an issue. I can easily slip enough to easily take off. Do I stall the engine???. If Im not paying attention, it happens every now and them. Do I wish it had LESS PEDDLE PRESSURE. Sure! But, I'm use to it now and will live with it for the reliability.
My SPEC has been error free and I serve it plenty of abuse. Granted, I'm only at 450 RWHP, but I cant complain... That's why I installed it! OVERKILL!
For some, its a LOVE or HATE the SPEC relationship.
Bill
SPEC Twin was $1300. back then!
SO,, Approx. 12 Forum Members got together and contacted SPEC and they did a GROUP PURCHASE us. If I remember correctly it was right around $1100.
Shortly after purchase, several of the Group Purchase guys had some serious SPEC Clutch installation & reliability issues. Slippage, warped disk, burnt up throw out bearings, sever vibration issues, etc..... Spec took care of the warped disk issues..
I thought I wasted my hard earned clutch money.
Here's what panned out and why some of those issues were encountered:
- The installation people failed to take the critical measurements needed for proper slave cylinder height and just installed the shim or didn't bother to install it at all.
The clutch would burn up very shortly after install OR not disengage and burn up the throw out bearing and or damage the synchros! -
- When the drive train was reinstalled into the bell housing (Trans/Differential & TT) all at once, the installers let the entire drivetrain weight rest inside the bell housing before the TT was fully inserted and bolted to the bell housing. That in turn bent the two disk hubs causing them to warp.
- Improper bleeding and improper TICK master cylinder adjustment was also another very common issue. Results in poor peddle engagement height, hard shifts or pressure plate damage.
-After fully understanding all of those issues and taking the proper steps to eliminate them, my SPEC Twin install went very well and it has been a really good clutch.
-Its not an ON/OFF engagement clutch. I have very good engagement and release height.
My wife on occasion has driven the car with out too much bitching. The TICK high volume Master makes the peddle much more stiff than if I would have used a normal volume Tick or an OEM master. At that time, only the high volume TICK was being offered.
I used great pains measure both critical measurements to determine shim size for the slave cylinder despite EVERYONES recommendation to JUST INSTALL the shim that came with the clutch. In my case, NO SHIM was needed for proper slave height. I remembered that I measured everything 4-5 times!
-I made a decision to break up the drive train into TWO parts. The transmission & differential as one install and the Torque tube as a separate install. Installing the TT into the new clutch is SO much easier and there is little if any chance of bending the disk hubs.
I went to great pains to not have issues with drive train harmonics/ vibrations. I had the SPEC Flywheel matched balanced to the old OEM ZO6 Fly wheel and installed the new flywheel in the same relationship back on the crank. NO VIBRATIONS.
I spent a good number of hours adjusting and readjusting the clutch peddle adjustment rod to get proper peddle height, correct clutch disengagement and engagement. I have a fairly big cam so, take off from a dead stop would sound like it could be an issue. I can easily slip enough to easily take off. Do I stall the engine???. If Im not paying attention, it happens every now and them. Do I wish it had LESS PEDDLE PRESSURE. Sure! But, I'm use to it now and will live with it for the reliability.
My SPEC has been error free and I serve it plenty of abuse. Granted, I'm only at 450 RWHP, but I cant complain... That's why I installed it! OVERKILL!
For some, its a LOVE or HATE the SPEC relationship.
Bill
Last edited by Bill Curlee; 01-05-2016 at 02:06 PM.
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~STOLEN~ (01-05-2016)
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~STOLEN~ (01-05-2016)
#19
Le Mans Master
I really like my RXT. I suggested it to my friend, and he got one, and really likes it too. They have a newer 1200hp RXT version that might be better if you are drag racing.
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~STOLEN~ (01-06-2016)