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Spec Clutches? Looking for some advice

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215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
Hey everyone! Haven't been on for a while with all the crazy stuff going on right now. I hope everyone has remained in good health. I've just spent the last 2 hours browsing the forum trying to catch up. I haven't been to the track since last December. I had a feeling that a clutch replacement may be coming due and didn't want to chance another event with it. And what do you know, only 400 mile on the odometer since my last event in December and the clutch went out on me last week (in the driveway thankfully).

I have some questions about Spec Clutches. I did some searches and couldn't quite find an answer. My car is 2016 GTPP that I hit the track with 6+ events a year. 3680 lbs at the scales with a half tank of gas and me out of the car. Multiple suspension mods, but only a Ford Performance Power Pack 3 tune for additional power. 28K miles. It's not my daily, but I do like driving on the street with it.

I know a lot of people like to run the Exedy Hyper Single clutch. However, I've heard and read good things about Spec and decided to contact them for a recommendation. I know that some people tend to overspend when it comes to clutches and wanted to hear what they had to say. Their recommendation surprised me. According to them, they recommend their Stage 1 clutch with the billet aluminum pressure plate and aluminum flywheel. Their response is below.

"Thank you for the inquiry. For road course use, go as light as you can and it still be comfortable to drive wherever else you drive it. There are huge power, reliability and safety gains with the lightweight parts. If you still want it to be comfortable driving around town or on an off a trailer, etc, go with our lightweight single disc setup. Stage 1 is plenty (550 ft lbs tq and over 600 hp).

So I recommend, budget allowing, the Stage 1 clutch with billet lightweight pressure plate option and billet aluminum flywheel. This set will drop approx. 20 lbs off your rotating assembly, which is better for the car and your lap times. One other note is the lightweight pressure plate is much more resistant to damage should you overrev, badly miss a gear, suffer engine failure at high rpm, etc.. They pretty much never break straps, even with a big mistake.

I know that is a lot of info…please feed me any questions."


A 20 lb loss is quite a bit so I asked about drivability issues with stop and go traffic. Reading forums you see a lot of people saying to stay away from an aluminum flywheel. So I asked about it and this is what they said.

"No, that is bad info..car doesn’t know what material flywheel is in the car…it’s all about the mass vs drivability, and dropping 20 lbs will not make starts a bad experience.

If you had a 4K lb car w/ a V6 and 2.73 gearing , it would feel less friendly. But a late model Coyote car is going to drive just fine with this setup, which is why we sell thousands of them a season for street driven cars. And the aluminum is aircraft quality and has even better integrity at rpm than most steel. All our units are SFI certified. We use the aluminum parts in 2000hp drag setups (but with 2 discs instead of 1)."


I briefly checked around on pricing and that setup would put me in the neighborhood of the Exedy clutch. I don't know what the the weight loss is with the Exedy clutch, however, I believe that the Spec clutch would be a bit more driver friendly? Does anyone else have experience with this clutch?
 

PatientZero

@restless_performance
825
865
Exp. Type
Autocross
Exp. Level
10-20 Years
Kansas City, Missouri
I had an ACT lightweight flywheel on my car for a year and I HATED IT. For a pure track car there is definitely merit in getting rid of that rotating mass but if you're driving the car on the street I would not go that route. Is it possible to keep a steel flywheel and the aluminum pressure plate to drop some weight without going so extreme?
 
6,363
8,187
Dude, drop the 20 pounds and hang on.....you'll thank me later,
I put aluminum wheels in everything I own.(that's legal)
I've never had an issue when you buy the entire clutch/flywheel/pressure plate kit from the same manufacturer. If you think 20 pounds might be too much,(I don't ) find one that drops 10 or 15. I had an aluminum wheel in my 99 4.6 and loved it., but it did have 3.55 gears in it.
 
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675
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Depending on what revs you use, the Spec Stg 1 might not be a good choice. I had one in my Boss 302 and the clutch still locked me out of gears above 7k rpm just like the OE clutch did. McLeod RST cured it 100%.

I did have the aluminum flywheel with the Spec and it was nice especially when heel n toe'ing blips. No downside to the aluminum at all.
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
Dude, drop the 20 pounds and hang on.....you'll thank me later,
I put aluminum wheels in everything I own.(that's legal)
I've never had an issue when you buy the entire clutch/flywheel/pressure plate kit from the same manufacturer. If you think 20 pounds might be too much,(I don't ) find one that drops 10 or 15. I had an aluminum wheel in my 99 4.6 and loved it., but it did have 3.55 gears in it.
I think I read in my research somewhere that you loved aluminum flywheels. It really does seem to be hit and miss with people. Spec seems to stand by their claim that drivability won't suffer. I don't expect it to be like stock, but at the same time I don't want a finicky clutch in stop and go traffic. I really do want to take advantage of the lighter weight if I can get away with it.
Depending on what revs you use, the Spec Stg 1 might not be a good choice. I had one in my Boss 302 and the clutch still locked me out of gears above 7k rpm just like the OE clutch did. McLeod RST cured it 100%.

I did have the aluminum flywheel with the Spec and it was nice especially when heel n toe'ing blips. No downside to the aluminum at all.
The S550 doesn't have the gear lock out problem. Plus, I have an MGW shifter installed. I do upshift quite a bit at 7200 -7400 RPM's at the track though. The stock clutch didn't complain, but it also may be one of the contributors for it's early demise (which I expected, regardless).
I had an ACT lightweight flywheel on my car for a year and I HATED IT. For a pure track car there is definitely merit in getting rid of that rotating mass but if you're driving the car on the street I would not go that route. Is it possible to keep a steel flywheel and the aluminum pressure plate to drop some weight without going so extreme?
They do have an option for a billet steel flywheel with a weight reduction from their standard 21 lbs to 16.9 lbs. I don't know what the O.E.M. flywheel weighs.

I guess what surprised me the most is I thought for sure they would recommend a Stage 2+ or Stage 3. They said it was not necessary though.
 

PatientZero

@restless_performance
825
865
Exp. Type
Autocross
Exp. Level
10-20 Years
Kansas City, Missouri
I think the main thing you gain with the Stage 2, 3, etc. is more clamping force to hold more power. If you're making stock(ish) power then there is no need for that. If you can, try to find someone with a lightweight flywheel and drive their car to see if you like it. Like I said, on the track there is no downside but street driving is where I did not like it. Everyone has a different preference.
 

Wingrider

'11 GT500, 99% Track Car. Lots of mods & I coach
I have a SPEC clutch in my 2011 GT500 w/ the SVPP 750HP upgrade. Spins up a lot faster and good street ability. Not as buttery smooth as the stock one was but totally manageable and most of the time it can be as smooth. It's just a little different and feels more direct with at times a little less slip. It likes on/off use.
I (think) there was an 800hp and a 1300hp version, but I went with the higher hp. I like it and would get another one when this one goes.
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
I have a SPEC clutch in my 2011 GT500 w/ the SVPP 750HP upgrade. Spins up a lot faster and good street ability. Not as buttery smooth as the stock one was but totally manageable and most of the time it can be as smooth. It's just a little different and feels more direct with at times a little less slip. It likes on/off use.
I (think) there was an 800hp and a 1300hp version, but I went with the higher hp. I like it and would get another one when this one goes.
Thanks for the input. I'm going to place a call with them today to chat more on the phone instead of email. I put a hold on my purchase based on some of the responses I've received here. I'm not expecting a stock clutch experience, but at the same time, I don't want something I later regret. Changing a clutch on jack stands is something I don't want to do more than I have to.
 
i have a soec stage 2+ with aluminum fly wheel and billet pressure plate option. its a bad ass zero complaints clutch andnits light total weight 32.5lbs! thats only 5 pounds more than my pals RTS twin carbon billet. for the mustang the stage 2* is awesome and it resists melting (ive tried hard) and above 8000 i rarely if ever have any hydraulic issues or pedal issues (trying to remember).. no issues at waterford hills
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
So, I put in a call to Spec to chat with them rather than email. I'm fairly convinced after speaking with them that I'm not going to experience any dramatic differences in driving on the street other than having to adjust somewhat to the expected normal behavior of an aluminum flywheel when leaving from dead stops. The guy I spoke with has actually driven with both steel and aluminum and assured me that it's not that big a difference and easy to adjust to.

However, what I did learn is that he said to expect to hear some rattling noise at idle. He stated it is fairly common for the S550 with an aluminum flywheel (apparently not so with the Camaro). With an aftermarket exhaust he said I may not hear it as much if at all. In making my decision, I'm just going to assume that I will hear it regardless. So... I need to decide if a bit of noise is going to be OK with me as a trade off for all the other benefits at the track.

@blacksheep-1, have you experienced this noise?
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
i have a soec stage 2+ with aluminum fly wheel and billet pressure plate option. its a bad ass zero complaints clutch andnits light total weight 32.5lbs! thats only 5 pounds more than my pals RTS twin carbon billet. for the mustang the stage 2* is awesome and it resists melting (ive tried hard) and above 8000 i rarely if ever have any hydraulic issues or pedal issues (trying to remember).. no issues at waterford hills
That's good to hear, thanks. Is this with an S550? I did ask them about the Stage 2 and 2+, but they didn't recommend it stating that Kevlar is not the best choice for the track because it can glaze over if it gets hot. Glad to know it's working great for you though.
 
6,363
8,187
So, I put in a call to Spec to chat with them rather than email. I'm fairly convinced after speaking with them that I'm not going to experience any dramatic differences in driving on the street other than having to adjust somewhat to the expected normal behavior of an aluminum flywheel when leaving from dead stops. The guy I spoke with has actually driven with both steel and aluminum and assured me that it's not that big a difference and easy to adjust to.

However, what I did learn is that he said to expect to hear some rattling noise at idle. He stated it is fairly common for the S550 with an aluminum flywheel (apparently not so with the Camaro). With an aftermarket exhaust he said I may not hear it as much if at all. In making my decision, I'm just going to assume that I will hear it regardless. So... I need to decide if a bit of noise is going to be OK with me as a trade off for all the other benefits at the track.

@blacksheep-1, have you experienced this noise?

it seems to be a Ford thing, my GT500 rattles a bit at idle, put a bit of pressure on the pedal, or put it in gear, it stops. I'm not sure it's the clutch, it may be the Tremec input shaft rattling around, remarkably, the aluminum flywheel in my SN95 didn't rattle, the Iron wheel in my Shelby does. But it did with the stock clutch as well so I tend to believe it's the trans more than the clutch.
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
Thanks. Slight noise like that I can put up with. I've been doing some research and it seems that aluminum flywheels have a tendency to amplify gear rollover noise. I guess the heavier flywheels do a better job of masking it. Plus, it can depend on the transmission. This video gives a quick explanation.
<iframe width="560" height="315" src="
" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
Hey everyone! Haven't been on for a while with all the crazy stuff going on right now. I hope everyone has remained in good health. I've just spent the last 2 hours browsing the forum trying to catch up. I haven't been to the track since last December. I had a feeling that a clutch replacement may be coming due and didn't want to chance another event with it. And what do you know, only 400 mile on the odometer since my last event in December and the clutch went out on me last week (in the driveway thankfully).

I have some questions about Spec Clutches. I did some searches and couldn't quite find an answer. My car is 2016 GTPP that I hit the track with 6+ events a year. 3680 lbs at the scales with a half tank of gas and me out of the car. Multiple suspension mods, but only a Ford Performance Power Pack 3 tune for additional power. 28K miles. It's not my daily, but I do like driving on the street with it.

I know a lot of people like to run the Exedy Hyper Single clutch. However, I've heard and read good things about Spec and decided to contact them for a recommendation. I know that some people tend to overspend when it comes to clutches and wanted to hear what they had to say. Their recommendation surprised me. According to them, they recommend their Stage 1 clutch with the billet aluminum pressure plate and aluminum flywheel. Their response is below.

"Thank you for the inquiry. For road course use, go as light as you can and it still be comfortable to drive wherever else you drive it. There are huge power, reliability and safety gains with the lightweight parts. If you still want it to be comfortable driving around town or on an off a trailer, etc, go with our lightweight single disc setup. Stage 1 is plenty (550 ft lbs tq and over 600 hp).

So I recommend, budget allowing, the Stage 1 clutch with billet lightweight pressure plate option and billet aluminum flywheel. This set will drop approx. 20 lbs off your rotating assembly, which is better for the car and your lap times. One other note is the lightweight pressure plate is much more resistant to damage should you overrev, badly miss a gear, suffer engine failure at high rpm, etc.. They pretty much never break straps, even with a big mistake.

I know that is a lot of info…please feed me any questions."


A 20 lb loss is quite a bit so I asked about drivability issues with stop and go traffic. Reading forums you see a lot of people saying to stay away from an aluminum flywheel. So I asked about it and this is what they said.

"No, that is bad info..car doesn’t know what material flywheel is in the car…it’s all about the mass vs drivability, and dropping 20 lbs will not make starts a bad experience.

If you had a 4K lb car w/ a V6 and 2.73 gearing , it would feel less friendly. But a late model Coyote car is going to drive just fine with this setup, which is why we sell thousands of them a season for street driven cars. And the aluminum is aircraft quality and has even better integrity at rpm than most steel. All our units are SFI certified. We use the aluminum parts in 2000hp drag setups (but with 2 discs instead of 1)."


I briefly checked around on pricing and that setup would put me in the neighborhood of the Exedy clutch. I don't know what the the weight loss is with the Exedy clutch, however, I believe that the Spec clutch would be a bit more driver friendly? Does anyone else have experience with this clutch?
Hello Nvrfinished ...... I replaced the stock clutch on my 2013 Boss 302 with a Spec 1. I could not make quick shifts and had continuous 1-2 lockouts with the stock clutch. The Spec 1 took care of this issue completely. There was some chatter initially but after putting on about 1,000 miles it smoothed out. A bit more pedal pressure and it engages more toward the top of the pedal travel, but I am very happy with the Spec 1. I did also replace the stock flywheel with a lightened steel unit. It feel like it rev's quicker. Hope this helps!!!
 
215
210
Exp. Type
HPDE
Exp. Level
Under 3 Years
SoCal
Thanks! I've already decided to purchase the Spec Stage 1 with the aluminum pressure plate. I'm still on the fence though about the aluminum flywheel. I need to make up my mind soon.

Something else has just occurred to me though. I wonder if I should be sending the MT82 with 28k miles on it to Ben Calimer for a Stage 1 rebuild while it's out? Yikes... more $$$
 

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