Replacement for LS7 clutch?
Thread Starter
Joined: Jan 2002
Posts: 4,072
Likes: 75
From: Casselberry FL
Replacement for LS7 clutch? Vehicle is a daily driver which sees 400-600 miles per month almost completely stop'n'go city traffic, but I may go back to autocrossing it or try HPDE at some point. I don't visit drag strips, but there are the rare street encounters.
I want to rebuilt my top-end and I am worried that my current clutch setup will be inadequate. What I have now is a LS7 clutch with Fidanza flywheel and Tick MC; it was installed in March 2009 so I am not sure which MC bore I have, but I'm guessing it was the larger 7/8" due to the order date. In addition, I have a rear main seal leak so I figured I might as well have the replacement clutch ready at the same time as the leak is fixed.
I'm looking for a clutch which has similar manners to what I have now but with greater holding power... not knowing what to expect with the top-end rebuild, I think supporting 600rwhp/600rwtq would provide plenty of overhead. The RPS BC2 is a little (okay, a LOT) more than I'd like to spend, and it's designed for the 3/4" MC bore. The Katech LS9X for F-bodies is a little less expensive and Jason says it will work fine for either MC bore size, but I'm gaining a few pounds over what I have now. The LS9X is more expensive for the F-body since more customizations were needed to make it compatible. Could I buy an expensive clutch, sure... but I would prefer not to get more than I need everything else being equal.
Are there other clutches out there which will give me very long life, ease of use, zero chatter, soft pedal and similar performance? I definitely want a lightweight flywheel option (12-13lbs), but I don't want to drop so much weight that it causes drivability problems.
I want to rebuilt my top-end and I am worried that my current clutch setup will be inadequate. What I have now is a LS7 clutch with Fidanza flywheel and Tick MC; it was installed in March 2009 so I am not sure which MC bore I have, but I'm guessing it was the larger 7/8" due to the order date. In addition, I have a rear main seal leak so I figured I might as well have the replacement clutch ready at the same time as the leak is fixed.
I'm looking for a clutch which has similar manners to what I have now but with greater holding power... not knowing what to expect with the top-end rebuild, I think supporting 600rwhp/600rwtq would provide plenty of overhead. The RPS BC2 is a little (okay, a LOT) more than I'd like to spend, and it's designed for the 3/4" MC bore. The Katech LS9X for F-bodies is a little less expensive and Jason says it will work fine for either MC bore size, but I'm gaining a few pounds over what I have now. The LS9X is more expensive for the F-body since more customizations were needed to make it compatible. Could I buy an expensive clutch, sure... but I would prefer not to get more than I need everything else being equal.
Are there other clutches out there which will give me very long life, ease of use, zero chatter, soft pedal and similar performance? I definitely want a lightweight flywheel option (12-13lbs), but I don't want to drop so much weight that it causes drivability problems.
The monster LT1 setup would probably work, or you could just buy a new insert for the flywheel and buy a McLeod RST. I've driven an RXT before in stop and go (Houston) traffic and didn't even flinch in a 700 RWHP GT500. You can always sell the tick and buy the 3/4's master.
Vehicle is a daily driver which sees 400-600 miles per month almost completely stop'n'go city traffic, but I may go back to autocrossing it or try HPDE at some point. I don't visit drag strips, but there are the rare street encounters.
I want to rebuilt my top-end and I am worried that my current clutch setup will be inadequate. What I have now is a LS7 clutch with Fidanza flywheel and Tick MC; it was installed in March 2009 so I am not sure which MC bore I have, but I'm guessing it was the larger 7/8" due to the order date. In addition, I have a rear main seal leak so I figured I might as well have the replacement clutch ready at the same time as the leak is fixed.
I'm looking for a clutch which has similar manners to what I have now but with greater holding power... not knowing what to expect with the top-end rebuild, I think supporting 600rwhp/600rwtq would provide plenty of overhead. The RPS BC2 is a little (okay, a LOT) more than I'd like to spend, and it's designed for the 3/4" MC bore. The Katech LS9X for F-bodies is a little less expensive and Jason says it will work fine for either MC bore size, but I'm gaining a few pounds over what I have now. The LS9X is more expensive for the F-body since more customizations were needed to make it compatible. Could I buy an expensive clutch, sure... but I would prefer not to get more than I need everything else being equal.
Are there other clutches out there which will give me very long life, ease of use, zero chatter, soft pedal and similar performance? I definitely want a lightweight flywheel option (12-13lbs), but I don't want to drop so much weight that it causes drivability problems.
I want to rebuilt my top-end and I am worried that my current clutch setup will be inadequate. What I have now is a LS7 clutch with Fidanza flywheel and Tick MC; it was installed in March 2009 so I am not sure which MC bore I have, but I'm guessing it was the larger 7/8" due to the order date. In addition, I have a rear main seal leak so I figured I might as well have the replacement clutch ready at the same time as the leak is fixed.
I'm looking for a clutch which has similar manners to what I have now but with greater holding power... not knowing what to expect with the top-end rebuild, I think supporting 600rwhp/600rwtq would provide plenty of overhead. The RPS BC2 is a little (okay, a LOT) more than I'd like to spend, and it's designed for the 3/4" MC bore. The Katech LS9X for F-bodies is a little less expensive and Jason says it will work fine for either MC bore size, but I'm gaining a few pounds over what I have now. The LS9X is more expensive for the F-body since more customizations were needed to make it compatible. Could I buy an expensive clutch, sure... but I would prefer not to get more than I need everything else being equal.
Are there other clutches out there which will give me very long life, ease of use, zero chatter, soft pedal and similar performance? I definitely want a lightweight flywheel option (12-13lbs), but I don't want to drop so much weight that it causes drivability problems.
http://monsterclutches.com/1998-2002...t-fbody-clutch
Also keep in mind the lighter you go with the clutch set-up, the more aggressive it will feel. That's why for street driving we recommend a heavier setup. If you are going to do some autocross or HPDE events, the LT1-S with our Lightweight flywheel would be a great overall clutch.
Feel free to give us a shout, or email Jacob@monsterclutches.com if you have any questions.
Thread Starter
Joined: Jan 2002
Posts: 4,072
Likes: 75
From: Casselberry FL
Not excited about gaining 5lbs of flywheel weight with the lightweight LT1-S flywheel. Excluding the flywheels, what's the weight difference of the LT1-S clutch & pressure plate compared to the LS7 pieces?
Found the following review on CF, what is the owner referring to by hot balancing issues? I don't want to revisit the problems I had with non-GM clutches or receive grief from my clutch/tranny tech I've been using for 15 years about straying away from a proven solution. I don't want any band aids to get it to work like GM, including but not limited to using shims.
http://www.corvetteforum.com/forums/...t-in-here.html
Some vendors say it comes with just a 1 year warranty against defects, another vendor says it comes with a 2 year warranty which can be extended if you buy the rebuild kit. If I don't have to rebuild it for say 5 years, and then I rebuild it, do I get a new 2 year warranty, or does it need to be continuously under warranty to get the extension? How long will you support this warranty cycle?
McLeod RST & Street Twin also seem to be in the running for the ~$1200 price point including a lightweight flywheel.
Found the following review on CF, what is the owner referring to by hot balancing issues? I don't want to revisit the problems I had with non-GM clutches or receive grief from my clutch/tranny tech I've been using for 15 years about straying away from a proven solution. I don't want any band aids to get it to work like GM, including but not limited to using shims.
http://www.corvetteforum.com/forums/...t-in-here.html
Some vendors say it comes with just a 1 year warranty against defects, another vendor says it comes with a 2 year warranty which can be extended if you buy the rebuild kit. If I don't have to rebuild it for say 5 years, and then I rebuild it, do I get a new 2 year warranty, or does it need to be continuously under warranty to get the extension? How long will you support this warranty cycle?
McLeod RST & Street Twin also seem to be in the running for the ~$1200 price point including a lightweight flywheel.
Last edited by JimMueller; May 13, 2016 at 09:23 PM.
Thread Starter
Joined: Jan 2002
Posts: 4,072
Likes: 75
From: Casselberry FL
So the Fidanza flywheel steel insert won't have the same concern as the stock cast iron flywheels have with a more aggressive disc material?
https://ls1tech.com/forums/manual-tr...you-using.html
LT1-S: Must use their heavier flywheel. 9.5" clutch diameter vs 12" diameter that I have now. I read that it's 49.5lbs total, is that with the 18 or 28lb flywheel? What are the diameters of both flywheels? SNL states no shimming is needed, bolt on and go, that's a definite plus. Confusion on the warranty period and a rumored rebuild kit which extends that warranty. Rated to 700rwhp/700rwtq.
RST: You can buy their flywheels or re-use an existing flywheel, although SNL seems to advocate this as a weak point with the stock cast flywheel. 10" clutch diameter compared to 12" now. I've read about some people having install challenges a few years ago, have those issues been resolved and it's a complete bolt-on and go setup as well? McLeod seems to sell both steel & lightweight flywheels... unclear on the weight & diameters. I've read of some people only getting a couple of years out of this clutch. Rated to 800bhp.
How does the MOI compare between the LS7 w/ 13lb flywheel, the LT1S with the 18lb flywheel, and the RST with the 13lb flywheel? Would I experience any different behavior with the larger MC bore with these two clutches? The engagement window will remain the same? I'd rather not change MC's if it's not required.
What other factors do I need to consider?
https://ls1tech.com/forums/manual-tr...you-using.html
LT1-S: Must use their heavier flywheel. 9.5" clutch diameter vs 12" diameter that I have now. I read that it's 49.5lbs total, is that with the 18 or 28lb flywheel? What are the diameters of both flywheels? SNL states no shimming is needed, bolt on and go, that's a definite plus. Confusion on the warranty period and a rumored rebuild kit which extends that warranty. Rated to 700rwhp/700rwtq.
RST: You can buy their flywheels or re-use an existing flywheel, although SNL seems to advocate this as a weak point with the stock cast flywheel. 10" clutch diameter compared to 12" now. I've read about some people having install challenges a few years ago, have those issues been resolved and it's a complete bolt-on and go setup as well? McLeod seems to sell both steel & lightweight flywheels... unclear on the weight & diameters. I've read of some people only getting a couple of years out of this clutch. Rated to 800bhp.
How does the MOI compare between the LS7 w/ 13lb flywheel, the LT1S with the 18lb flywheel, and the RST with the 13lb flywheel? Would I experience any different behavior with the larger MC bore with these two clutches? The engagement window will remain the same? I'd rather not change MC's if it's not required.
What other factors do I need to consider?
You don't have a cast flywheel, they're talking about a stock flywheel, your fidanza will work just fine. The stock flywheels supposedly don't hold up to the heat. The RST has a much lower MOI than an ls7 clutch.
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Thread Starter
Joined: Jan 2002
Posts: 4,072
Likes: 75
From: Casselberry FL
FYI, I asked the ? to Billy @ McLeod, his reply:
"The RST/RXT pressure plate is designed with the factory hydraulics stroke of .440” in mind, thus requiring factory master & slave to be used for proper operation."
"The RST/RXT pressure plate is designed with the factory hydraulics stroke of .440” in mind, thus requiring factory master & slave to be used for proper operation."
Looks like the RST is designed for the factory MC. I wonder if that means it has to be completely OEM, or just the OEM bore? Are the only side effects of using what I currently have be a narrower engagement window? It should be the same window as I'm accustomed to now, right?
--------------------
Our Monsters are setup for factory pedal throw and fluid displacement, when you do a conversion car this obviously isn't going to be the same. You may have to make some "adjustments".
Looks like the same thing for the LT1-S?
--------------------
I recently upgraded to the RST from McLeod. Great clutch but the engagement window is narrow. I had a Tick master installed at the time and the clutch was difficult to modulate (for me). I went to a factory master and the window improved but it still is small compared to what I'm looking for. I'm planning on pulling out the RST and swapping in something that feels more like a stock clutch.
The guy above didn't like the narrow engagement window, but that has nothing to do with the clutch kit, correct? Only the hydraulics?
--------------------
I'm seeing a few references to the ACT Twin but not any details. Should that be considered also?
Last edited by JimMueller; May 15, 2016 at 09:31 AM.
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12 Second Club
Joined: Sep 2005
Posts: 4,273
Likes: 0
From: Bucks County, Pa.
How do the Ram twin discs compare to the Monster and McLeod twins as far as; total weight for the assembly WITHOUT a flywheel, MOI due to assembly diameter, engagement window, longevity/durability, use in stop and go traffic, and master/slave needed to work properly??
BIG power handling is NOT a concern for me.
BIG power handling is NOT a concern for me.
FormerVendor
Joined: Nov 2007
Posts: 201
Likes: 0
Jim, our Dual-Friction clutch sounds like it would be right for you. The DF is quite popular since it has about the same pedal pressure as stock and plenty of holding power. We also offer lightened flywheels to work with this setup. If you have questions on anything, feel free to shoot us a PM or phone call!
For what you want the LT1-S Street twin from Monster would be perfect. Its rated for 700WHP/TQ and it drives like a stock clutch. In addition it will outlast any aftermarket single disc or multi-disc clutch.
http://monsterclutches.com/1998-2002...t-fbody-clutch
Also keep in mind the lighter you go with the clutch set-up, the more aggressive it will feel. That's why for street driving we recommend a heavier setup. If you are going to do some autocross or HPDE events, the LT1-S with our Lightweight flywheel would be a great overall clutch.
Feel free to give us a shout, or email Jacob@monsterclutches.com if you have any questions.
http://monsterclutches.com/1998-2002...t-fbody-clutch
Also keep in mind the lighter you go with the clutch set-up, the more aggressive it will feel. That's why for street driving we recommend a heavier setup. If you are going to do some autocross or HPDE events, the LT1-S with our Lightweight flywheel would be a great overall clutch.
Feel free to give us a shout, or email Jacob@monsterclutches.com if you have any questions.
Jim, our Dual-Friction clutch sounds like it would be right for you. The DF is quite popular since it has about the same pedal pressure as stock and plenty of holding power. We also offer lightened flywheels to work with this setup. If you have questions on anything, feel free to shoot us a PM or phone call!
I already have an SFI LS1 FW, Brand new, zero miles. I fugged up and purchased an LS7 clutch (also brand new) but realized that these two items dont work together.
Anywho, my combination is the following:
1987 Chevy Pick up
T56 trans
Stock LS1 shortblock
Ported 317 heads
custom cam & valvetrain
Maggie SC (smallest pulley would could get)
295/50-15 rear tires w/4.10 gears
I plan to terrorize my neighborhood and cruise ins. Also hit the track every now and then. But mainly, a street truck that will get driven quite often, back in forth to work/home, date nights with the wife, (I added Vintage Air) run my girls up to the park, etc etc I dont want a heavy *** pedal!!
To be fair, I was looking at the ACT clutch (GM9-HDSS) as well, but I didnt see them as a Sponsor in here.
Looking forward to your response and Thank you for your time.
Craig