[Clutch comparison] Katech LS9R::McCleod RXT::Mantic Twin Disk
04-30-2012, 10:53 PM
#41
Le Mans Master
You know why that happens right? The engine doesnt keep the moment of inertia as much so the tires dont light up as much. The engine rev's easier however it bogs down WAY easier. So i'm curious of different thoughts on this. Whats faster the slightly heavier clutch setup that pushes the car harder in the next gear or the one that can lose on the shifts if not perfect?
04-30-2012, 10:57 PM
#42
Tech Contributor
You know why that happens right? The engine doesnt keep the moment of inertia as much so the tires dont light up as much. The engine rev's easier however it bogs down WAY easier. So i'm curious of different thoughts on this. Whats faster the slightly heavier clutch setup that pushes the car harder in the next gear or the one that can lose on the shifts if not perfect?
I have a theory, which Justin is going to prove or disprove, that the heaver stock clutch which will take the slip makes launching a lot easier.
We shall see...
04-30-2012, 10:59 PM
#43
Racer
Yes. It will take a good 500 miles of normal driving to fully break in this clutch. After break in it got smooth and no chatter. I was working on my car this week end and checked the inside of the bell housing thru the vent holes. There is almost no clutch dust at all inside the bell housing after a year of driving. After all the driving and track runs my clutch fluid is clear with no discoloration. I have only changed once in the last year. A big difference over all my other clutches I have had in the car.
05-01-2012, 06:27 AM
#44
Instructor
Member Since: Apr 2012
Posts: 157
Likes: 0
Received 0 Likes
on
0 Posts
I have had the LS9X from Katech last year and now have the Mantic from ECS. Problems with LS9 clutch from Kaltech with 2,000 miles on it. One of the discs lost a clip in the center and caused an out of balance condition. Kateck did not stand behind it. said it was older than GM warranty on parts and did nothing to correct it. Last Katech part I will buy. ECS were stand up people on this and replaced it with a Mantic twin disc and only charged me for the additional Mantic parts. The Mantic is stronger and as smooth as the LS9 clutch. After break in it drives perfect with perfect shifting at all RPM,s I am putting 721 rwhp abd 655 tq thru it and it does not slip. Mantic is the way to go.
05-01-2012, 07:59 AM
#45
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
Good info, thank you. This clutch is a bear to drive in morning rush hour traffic, I can tell you that much. I have definitely had to adjust my driving style/habits to accompany the difference in take-off style. I had to change my driving habits when the cam went in as well so it's not a huge deal. It is something that I'm having to get used to though.
The chatter in first gear with what I could consider 'regular' slippage is a little annoying. I'm hopeful that with continued stop and go driving, it'll break in and be more forgiving.
I'm also learning that my gas pedal sensitivity sucks too. There is some significant dead space when trying to feather the throttle on take off. I don't know if this is something I can adjust in the tune, or if it's something that I'll just have to deal with, but I'd love a more responsive pedal, i.e. cable throttle instead of drive by wire.
My wifes Mini Cooper is drive by wire too, but her pedal feels just like a cable throttle--as fast as you can pedal/feather the car, the engine responds the same.
When I'm idling at 900 and just barely push on the pedal, I either get 1800 rpms or nothing, it's very difficult, if not impossible, to get the car to gradually increase revs from 900-2000.
The chatter in first gear with what I could consider 'regular' slippage is a little annoying. I'm hopeful that with continued stop and go driving, it'll break in and be more forgiving.
I'm also learning that my gas pedal sensitivity sucks too. There is some significant dead space when trying to feather the throttle on take off. I don't know if this is something I can adjust in the tune, or if it's something that I'll just have to deal with, but I'd love a more responsive pedal, i.e. cable throttle instead of drive by wire.
My wifes Mini Cooper is drive by wire too, but her pedal feels just like a cable throttle--as fast as you can pedal/feather the car, the engine responds the same.
When I'm idling at 900 and just barely push on the pedal, I either get 1800 rpms or nothing, it's very difficult, if not impossible, to get the car to gradually increase revs from 900-2000.
The following users liked this post:
HC Mechanic (06-05-2017)
05-01-2012, 08:19 AM
#47
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
Thanks Joe, I'll check into it. I remember looking at some stuff in that area of HPT and I feel like one of the tables was maxed out but I'm not sure which one.
05-01-2012, 10:06 AM
#48
Premium Supporting Vendor
Member Since: Oct 2004
Location: Providing the most proven supercharger kits for your C5/6/7 609-752-0321
Posts: 23,314
Received 1,085 Likes
on
656 Posts
Justin, I have heard from a couple guys that what you're hearing at idle with the pedal out has nothing to do with the clutch assembly, but the actual trans itself, since the lighter flywheel's rotating mass acts as less of a damper, so things bonk around a bit more back there. Solution, push in pedal...LOL
No firsthand experience, but this came from a GM tech and a builder I now here locally.
No firsthand experience, but this came from a GM tech and a builder I now here locally.
You and I both. Another 700 miles or so and I'll really lay into it. Right now, I'm just doing regular driving with the occasional 70% throttle blast, just to make sure everything is functioning correctly.
The car feels MUCH faster though, that is for sure--it also revs up much more quickly now and I find myself at 3800rpms without even trying. I'm really anxious to romp on it and do a 1st-2nd-3rd gear pull and see how it feels.
You know how your car feels when it makes a lot of power and you're not expecting it? That's what this feels like. I was very used to the 500whp from before and could drive on the edge of traction often and feel comfortable. With the new clutch and 3.90s, the car surprises me a LOT now. . .
The car feels MUCH faster though, that is for sure--it also revs up much more quickly now and I find myself at 3800rpms without even trying. I'm really anxious to romp on it and do a 1st-2nd-3rd gear pull and see how it feels.
You know how your car feels when it makes a lot of power and you're not expecting it? That's what this feels like. I was very used to the 500whp from before and could drive on the edge of traction often and feel comfortable. With the new clutch and 3.90s, the car surprises me a LOT now. . .
I have had the LS9X from Katech last year and now have the Mantic from ECS. Problems with LS9 clutch from Kaltech with 2,000 miles on it. One of the discs lost a clip in the center and caused an out of balance condition. Kateck did not stand behind it. said it was older than GM warranty on parts and did nothing to correct it. Last Katech part I will buy. ECS were stand up people on this and replaced it with a Mantic twin disc and only charged me for the additional Mantic parts. The Mantic is stronger and as smooth as the LS9 clutch. After break in it drives perfect with perfect shifting at all RPM,s I am putting 721 rwhp abd 655 tq thru it and it does not slip. Mantic is the way to go.
The following users liked this post:
HC Mechanic (06-05-2017)
05-01-2012, 10:15 AM
#49
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
Thanks for chiming in Doug. I'm patiently waiting for a proper breakin period before I really let the screws loose and see how it feels. Even with my ~60% throttle here and there, it feels much faster than before.
I upped the idle to 900 and that makes the neutral sound tolerable. I'm hoping it quiets down but if this is how it'll be, that's fine, I can deal with it. The clutch is super smooth going through the gears and the few times I've taken it to 5500, it shifted perfectly and VERY quickly. Did I mention I'm anxious to get the breakin completed?
Do you have any comment on the chatter in first gear takeoffs Doug? Is this something that people experience initially but goes away after breakin? When I first drove it after the install, it slipped as much as I wanted in first but now it chatters and fights back if I try and baby it off the line.
I upped the idle to 900 and that makes the neutral sound tolerable. I'm hoping it quiets down but if this is how it'll be, that's fine, I can deal with it. The clutch is super smooth going through the gears and the few times I've taken it to 5500, it shifted perfectly and VERY quickly. Did I mention I'm anxious to get the breakin completed?
Do you have any comment on the chatter in first gear takeoffs Doug? Is this something that people experience initially but goes away after breakin? When I first drove it after the install, it slipped as much as I wanted in first but now it chatters and fights back if I try and baby it off the line.
05-01-2012, 11:12 AM
#50
Le Mans Master
Good info, thank you. This clutch is a bear to drive in morning rush hour traffic, I can tell you that much. I have definitely had to adjust my driving style/habits to accompany the difference in take-off style. I had to change my driving habits when the cam went in as well so it's not a huge deal. It is something that I'm having to get used to though.
The chatter in first gear with what I could consider 'regular' slippage is a little annoying. I'm hopeful that with continued stop and go driving, it'll break in and be more forgiving.
I'm also learning that my gas pedal sensitivity sucks too. There is some significant dead space when trying to feather the throttle on take off. I don't know if this is something I can adjust in the tune, or if it's something that I'll just have to deal with, but I'd love a more responsive pedal, i.e. cable throttle instead of drive by wire.
My wifes Mini Cooper is drive by wire too, but her pedal feels just like a cable throttle--as fast as you can pedal/feather the car, the engine responds the same.
When I'm idling at 900 and just barely push on the pedal, I either get 1800 rpms or nothing, it's very difficult, if not impossible, to get the car to gradually increase revs from 900-2000.
The chatter in first gear with what I could consider 'regular' slippage is a little annoying. I'm hopeful that with continued stop and go driving, it'll break in and be more forgiving.
I'm also learning that my gas pedal sensitivity sucks too. There is some significant dead space when trying to feather the throttle on take off. I don't know if this is something I can adjust in the tune, or if it's something that I'll just have to deal with, but I'd love a more responsive pedal, i.e. cable throttle instead of drive by wire.
My wifes Mini Cooper is drive by wire too, but her pedal feels just like a cable throttle--as fast as you can pedal/feather the car, the engine responds the same.
When I'm idling at 900 and just barely push on the pedal, I either get 1800 rpms or nothing, it's very difficult, if not impossible, to get the car to gradually increase revs from 900-2000.
Round 2: Lets see how it compares on the drag strip.
So you went 10.6x with stock clutch in decent air?
Any other changes being made to the car?
Last edited by robz; 05-01-2012 at 11:14 AM.
05-01-2012, 11:13 AM
#51
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
Car has 3.90 gears now in addition to the new clutch.
05-01-2012, 11:21 AM
#52
Le Mans Master
I was hoping for a straight up comparison on the drag strip for overall et and launch.
It will still be interesting. Goodluck and get video.
05-01-2012, 11:24 AM
#53
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
Trust me, I went back and forth over that very decision for weeks.
In the end, the ease of the rear end swap while the drivetrain was out was too much to pass up at the expense of an absolute direct comparison of stock vs aftermarket clutch.
I was also worried about the repeated aggressive launching and the stock diff and didn't want to shatter my ~$750 core.
It's built up now so I feel more comfortable launching it over 6k.
Video is a given and I'm hopeful I'll have another GoPro or two for extra angles this next race season
05-01-2012, 11:59 AM
#54
Le Mans Master
Thanks. That means a lot coming from you
Trust me, I went back and forth over that very decision for weeks.
In the end, the ease of the rear end swap while the drivetrain was out was too much to pass up at the expense of an absolute direct comparison of stock vs aftermarket clutch.
I was also worried about the repeated aggressive launching and the stock diff and didn't want to shatter my ~$750 core.
It's built up now so I feel more comfortable launching it over 6k.
Video is a given and I'm hopeful I'll have another GoPro or two for extra angles this next race season
Trust me, I went back and forth over that very decision for weeks.
In the end, the ease of the rear end swap while the drivetrain was out was too much to pass up at the expense of an absolute direct comparison of stock vs aftermarket clutch.
I was also worried about the repeated aggressive launching and the stock diff and didn't want to shatter my ~$750 core.
It's built up now so I feel more comfortable launching it over 6k.
Video is a given and I'm hopeful I'll have another GoPro or two for extra angles this next race season
I"m looking forward to the runs aswell Justinjor. Did you get the BUILT rear from ECS when you got the clutch? So with gears and the new clutch with some half decent air you should be the seeing a better ET of .2-.3 better and should definitely 60ft harder now with the gears. That is going to be one VERY VERY impressive heads/cam C6. Keep up the great work Justin.
05-01-2012, 12:30 PM
#55
Le Mans Master
I"m looking forward to the runs aswell Justinjor. Did you get the BUILT rear from ECS when you got the clutch? So with gears and the new clutch with some half decent air you should be the seeing a better ET of .2-.3 better and should definitely 60ft harder now with the gears. That is going to be one VERY VERY impressive heads/cam C6. Keep up the great work Justin.
I'd like to see a .1 gain in 60' from an aftermarket clutch over the stock which some feel gives about .2 in overall et.
Then you have the lower mass and ease to powershift maybe adding another .1.
That would put this car in the mid 10.3x's which seems about right for the top dog and that's not including the built 3.90 diff. Should be intersting. He may challenge your zr1 times, pipe.
05-01-2012, 12:52 PM
#57
Tech Contributor
At the risk of pi$$ing a friend off...
I'm worried that that clutch is going to slow him down as it'll spin tires or bog.
He and I have really learned to use the clutch almost like a torque converter, or a clutch in a top fueler, that slips and locks up over time as opposed to locking up upon release and God bless the rest of the drivetrain.
My friend Double A Vette has had a heck of a time with his new dual clutch. He is so disgusted he won't drive the car anymore. He was turning 1.4's with his stock clutch.
And I truly hope I'm wrong. Justin is one of the quickest studies I've met so he's the perfect guy to try this out.
Time will tell.
I'm worried that that clutch is going to slow him down as it'll spin tires or bog.
He and I have really learned to use the clutch almost like a torque converter, or a clutch in a top fueler, that slips and locks up over time as opposed to locking up upon release and God bless the rest of the drivetrain.
My friend Double A Vette has had a heck of a time with his new dual clutch. He is so disgusted he won't drive the car anymore. He was turning 1.4's with his stock clutch.
And I truly hope I'm wrong. Justin is one of the quickest studies I've met so he's the perfect guy to try this out.
Time will tell.
05-01-2012, 01:09 PM
#58
Le Mans Master
Thread Starter
Member Since: May 2011
Location: Tampa FL (formerly Justinjor)
Posts: 5,022
Likes: 0
Received 14 Likes
on
9 Posts
Tech Contributor
St. Jude Donor '11-'12-'13-'14
You guys are putting a lot of pressure on me. I can't imagine I'll see a 10.39 but wow, that would certainly be awesome.
My car is still just a cam-only C6 coupe and will likely stay that way.
Intake, headers, UDP, ported TB, ported manifold, and cam are the only sources of extra power.
I hope you're wrong Joe and even still, that wouldn't **** me off anyway. It would just mean I'd have to try something else. I trust the guys at ECS and given they do a LOT of drag racing, I went with their recommendation.
I can't see the clutch slowing me down though but we'll have to see when push comes to shove. I need new drag radials right now so until I pick some up, I won't be at the track.
Why is it that you think I'll go slower Joe? Is it the idea that I can't slip on the launch anymore and thus my 60' will suffer?
.1 off my 60ft time would be incredible but I don't see it happening. Even if the car is capable of it, I don't have big enough ***** to launch it off the limiter with slicks to even attempt it.
I'd be happy with consistent low 1.5s-high 1.4s. I'm hopeful that the gear change will be enough to take the top spot.
My car is still just a cam-only C6 coupe and will likely stay that way.
Intake, headers, UDP, ported TB, ported manifold, and cam are the only sources of extra power.
I hope you're wrong Joe and even still, that wouldn't **** me off anyway. It would just mean I'd have to try something else. I trust the guys at ECS and given they do a LOT of drag racing, I went with their recommendation.
I can't see the clutch slowing me down though but we'll have to see when push comes to shove. I need new drag radials right now so until I pick some up, I won't be at the track.
Why is it that you think I'll go slower Joe? Is it the idea that I can't slip on the launch anymore and thus my 60' will suffer?
.1 off my 60ft time would be incredible but I don't see it happening. Even if the car is capable of it, I don't have big enough ***** to launch it off the limiter with slicks to even attempt it.
I'd be happy with consistent low 1.5s-high 1.4s. I'm hopeful that the gear change will be enough to take the top spot.
05-01-2012, 01:19 PM
#59
Tech Contributor
You guys are putting a lot of pressure on me. I can't imagine I'll see a 10.39 but wow, that would certainly be awesome.
My car is still just a cam-only C6 coupe and will likely stay that way.
Intake, headers, UDP, ported TB, ported manifold, and cam are the only sources of extra power.
I hope you're wrong Joe and even still, that wouldn't **** me off anyway. It would just mean I'd have to try something else. I trust the guys at ECS and given they do a LOT of drag racing, I went with their recommendation.
I can't see the clutch slowing me down though but we'll have to see when push comes to shove. I need new drag radials right now so until I pick some up, I won't be at the track.
Why is it that you think I'll go slower Joe? Is it the idea that I can't slip on the launch anymore and thus my 60' will suffer?
.1 off my 60ft time would be incredible but I don't see it happening. Even if the car is capable of it, I don't have big enough ***** to launch it off the limiter with slicks to even attempt it.
I'd be happy with consistent low 1.5s-high 1.4s. I'm hopeful that the gear change will be enough to take the top spot.
My car is still just a cam-only C6 coupe and will likely stay that way.
Intake, headers, UDP, ported TB, ported manifold, and cam are the only sources of extra power.
I hope you're wrong Joe and even still, that wouldn't **** me off anyway. It would just mean I'd have to try something else. I trust the guys at ECS and given they do a LOT of drag racing, I went with their recommendation.
I can't see the clutch slowing me down though but we'll have to see when push comes to shove. I need new drag radials right now so until I pick some up, I won't be at the track.
Why is it that you think I'll go slower Joe? Is it the idea that I can't slip on the launch anymore and thus my 60' will suffer?
.1 off my 60ft time would be incredible but I don't see it happening. Even if the car is capable of it, I don't have big enough ***** to launch it off the limiter with slicks to even attempt it.
I'd be happy with consistent low 1.5s-high 1.4s. I'm hopeful that the gear change will be enough to take the top spot.
I really hope I'm wrong. But if I'm not you'll want to look into getting bias ply rear tires...your rear end is not gonna like drag radials and dead hooking...built or not.
So my point is try your current tires before you buy new ones.
If it slips like the stock clutch, you'll be able to get lower than 1.48.
05-01-2012, 01:24 PM
#60
Safety Car
Looking forward to your track runs Justin.