Weight Reduction That Doesn't Ruin Your life/Safety, Thoughts?

[Theviking]

The Exedy Hyper single has a lightened chromoly flywheel and aluminum clutch cover, available in single or twin disc.
This is Kohr's "Go to" clutch for road racing. It's what I and many others here use....not sure if its the best but it works.

EH04SD1 Exedy Hyper Single Clutch BOSS S REPLACEMENT TREMEC | KohR Motorsports

kohrmotorsports.com

I had one of these in my car for a year before finally ditching it. Nice piece but not much fun for street driving as it's much harder to modulate from standing start. If you are running a dual purpose car I'd personally skip it.

 

[therealphee]

I had one of these in my car for a year before finally ditching it. Nice piece but not much fun for street driving as it's much harder to modulate from standing start. If you are running a dual purpose car I'd personally skip it.

This is why I went with a double disc setup. I really enjoy driving with the McLeod clutch. It’s also lighter and smaller diameter than stock

 

[Theviking]

@SMGDHG I would consider taking the K-member off your weight saving list. Lots of reports that the lightweight ones aren't strong enough for track driving and I don't think the good ones (like from Maximum Motorsport) save weight. Certainly there are other good reasons to get one, but not weight saving.

The Maximum Motorsports K-members is actually a few pounds heavier then stock if I remember correctly. But the piece of mind is definitely worth it here and it's held up well so far with mixed driving.

 

[Fabman]

This is why I went with a double disc setup. I really enjoy driving with the McLeod clutch. It’s also lighter and smaller diameter than stock

I had the Mcleod twin disc on my 700/700 stroker 3 valve and it drove like stock on the street, just a little rattling from the mid plate but it was very streetable.
I don't street drive the car anymore since I went to the Coyote and Exedy Hyper single, but I'm surprised to hear Theviking didn't like it on the street.
@Mad Hatter you drive yours on both the street and track...what do you think of the driveability?
My experience is track only though it loads up in the trailer just fine and there's a lot of effing around to get that fat b!tch stuffed in there.
Anybody else have one.....? Inquiring minds want to know....

 

[biggsy]

Aluminum diff cover may help with weight savings

 

[JDee]

I have an Exedy hyper single. It's a vast improvement for the track over the stock clutch which is completely unsuitable for anything beyond very light duty track use. And I do mean light duty, once you get working the car hard the stock clutch will die quickly. Can't take the heat.
I only drove the Exedy on street for a bit to break it in, I wouldn't want it in a street car, it's pretty aggressive. Particularly you don't want to try to slip it. It also doesn't like reverse. Fortunately, I don't drive backwards much.....
I use a winch to load the car on the trailer, it's way too hard on the clutch trying to sneak it up and onto a trailer.

 

[Mike_FL]

What about the Cortex K member? Should remove some weight off the front. If you’re feeling $$$ go for the for SLA

 

[SMGDHG]

What about the Cortex K member? Should remove some weight off the front. If you’re feeling $$$ go for the for SLA

I have this on order, it's also on my spreadsheet that I posted in this thread. It's a 20lb weight savings.

 

[SMGDHG]

I have an Exedy hyper single. It's a vast improvement for the track over the stock clutch which is completely unsuitable for anything beyond very light duty track use. And I do mean light duty, once you get working the car hard the stock clutch will die quickly. Can't take the heat.
I only drove the Exedy on street for a bit to break it in, I wouldn't want it in a street car, it's pretty aggressive. Particularly you don't want to try to slip it. It also doesn't like reverse. Fortunately, I don't drive backwards much.....
I use a winch to load the car on the trailer, it's way too hard on the clutch trying to sneak it up and onto a trailer.

I don't know much about clutches, but this is counter intuitive to me. The "wear" a clutch would see is only when your foot is on the clutch pedal right?

With that being said, stop and go commuting (i.e., spending the largest % of time with your foot on the clutch, thereby wearing the clutch) would be far more intensive on the clutch than a lap at the race track. Also, if heat is the enemy.....at track speeds, the engine is spinning faster, and the air under the car is moving at a more frequent rate, both of which should help with cooling the clutch, no?

FWIW, I am on a 100% stock clutch on my car. I installed a fresh OEM style clutch 3 years ago, and have been to over 40 track days since, most of which time trial competing in advanced groups . I've never experienced a race style clutch, but I've also never had a single issue with my stock style clutch. So perhaps I don't know what I'm missing.

I understand that the 400+WHP 7500RPM capable coyote and MT-82 is a much different animal than my 285whp 6500RPM 3v w/TR-3650, but my experience with a stock style replacement clutch has been very positive, to the point where unless my clutch fails, I struggle to see how prematurely "upgrading" it would be worth it. 40+ track days of time trial level driving on mine.

 

[Fabman]

I don't know much about clutches, but this is counter intuitive to me. The "wear" a clutch would see is only when your foot is on the clutch pedal right?

With that being said, stop and go commuting (i.e., spending the largest % of time with your foot on the clutch, thereby wearing the clutch) would be far more intensive on the clutch than a lap at the race track. Also, if heat is the enemy.....at track speeds, the engine is spinning faster, and the air under the car is moving at a more frequent rate, both of which should help with cooling the clutch, no?

FWIW, I am on a 100% stock clutch on my car. I installed a fresh OEM style clutch 3 years ago, and have been to over 40 track days since, most of which time trial competing in advanced groups . I've never experienced a race style clutch, but I've also never had a single issue with my stock style clutch. So perhaps I don't know what I'm missing.

I understand that the 400+WHP 7500RPM capable coyote and MT-82 is a much different animal than my 285whp 6500RPM 3v w/TR-3650, but my experience with a stock style replacement clutch has been very positive, to the point where unless my clutch fails, I struggle to see how prematurely "upgrading" it would be worth it. 40+ track days of time trial level driving on mine.

The more power and rpm you have the harder it is on clutches.
The repeated hard shifting and especially down shifting is tough on them too. The stock Coyote clutches are well known for locking out at high rpm making it impossible to shift. Air flowing under a car doesn’t have a large enough effect on a hot clutch inside of a bell housing. Maybe if cold air was ducted into and then out of the bell housing like you would with brake rotors it would help, but I’ve never seen that done. You’d still need to address the high rpm issues. The heavier s550’s with more power/rpm push the limits farther than the early 3v s197’s.

 

[Fabman]

What about the Cortex K member? Should remove some weight off the front. If you’re feeling $$$ go for the for SLA

Definitely a nice piece.

 

[stevbd]

I understand that the 400+WHP 7500RPM capable coyote and MT-82 is a much different animal than my 285whp 6500RPM 3v w/TR-3650, but my experience with a stock style replacement clutch has been very positive, to the point where unless my clutch fails, I struggle to see how prematurely "upgrading" it would be worth it. 40+ track days of time trial level driving on mine.

I think you are right that the extra 1,000 rpm redline is the difference maker.

Like you I have almost 160,000 miles on a totally stock gen1 coyote drivetrain, all original mt82/clutch etc., 40 plus track days, advanced HPDE level pace. Buuuuttt... I usually short shift at about 6500 and redline on my car is only 6900. Power falls off after 6500 on a stock gen1 coyote so there is little advantage to wringing it out. I have trouble fixing what isn't really broken but sooner or later I will probably upgrade the clutch and tune the motor for a higher redline and have some more fun.

 

[biggsy]

It also doesn't like reverse.

What do you mean by this?

 

[Mad Hatter]

I had the Mcleod twin disc on my 700/700 stroker 3 valve and it drove like stock on the street, just a little rattling from the mid plate but it was very streetable.
I don't street drive the car anymore since I went to the Coyote and Exedy Hyper single, but I'm surprised to hear Theviking didn't like it on the street.
@Mad Hatter you drive yours on both the street and track...what do you think of the driveability?
My experience is track only though it loads up in the trailer just fine and there's a lot of effing around to get that fat b!tch stuffed in there.
Anybody else have one.....? Inquiring minds want to know....

No problem on the street for me with the Hyper.. Been stick in traffic many times with it and you just adapt and get used to it.

 

[Theviking]

I have an Exedy hyper single. It's a vast improvement for the track over the stock clutch which is completely unsuitable for anything beyond very light duty track use. And I do mean light duty, once you get working the car hard the stock clutch will die quickly. Can't take the heat.
I only drove the Exedy on street for a bit to break it in, I wouldn't want it in a street car, it's pretty aggressive. Particularly you don't want to try to slip it. It also doesn't like reverse. Fortunately, I don't drive backwards much.....
I use a winch to load the car on the trailer, it's way too hard on the clutch trying to sneak it up and onto a trailer.

No problem on the street for me with the Hyper.. Been stick in traffic many times with it and you just adapt and get used to it.

I had similar experiences to JDee. Difficult to slip/modulate smoothly when doing a lot of stop and go driving. I've been driving sticks since I've been driving (which was a loooong time ago) so not my first rodeo with clutches. You do get used to it, sort of, until stuck in a lot of stop and go traffic. In the end it just wasn't worth the trouble for me since I'm still doing more street driving then track days.

Still have the Hyper Single if someone is interested I will make a very good deal

 

[JDee]

What do you mean by this?

When you try to back up the thing will chatter and shudder pretty good, especially if you're backing uphill. I think it's because the reverse gear ratio seems to be a bit high and the inability to slip the clutch. I've learned how to manage it, primarily by trying to avoid getting into situations where reverse is needed.
Despite these issues, the clutch is great on track and that's really what's important to me as the car is never street driven any more.

 

[biggsy]

When you try to back up the thing will chatter and shudder pretty good, especially if you're backing uphill. I think it's because the reverse gear ratio seems to be a bit high and the inability to slip the clutch. I've learned how to manage it, primarily by trying to avoid getting into situations where reverse is needed.
Despite these issues, the clutch is great on track and that's really what's important to me as the car is never street driven any more.

Okay. I have had the Hyper Single for a year and a half now and always thought something was wrong when I put it in reverse. I assumed it to be a transmission issue but glad to know it is not.