Clutch Advice
01-25-2019, 10:06 PM
#1
Clutch Advice
After progressively declining shiftability in my C5Z track car over the last few months, followed by a dyno session today, I'm pretty sure my pilot bearing is dead (horrible noise getting moving from a stop). So, looking for suggestions for a replacement clutch kit.
Most specifically, looking for opinions on optimum performance/$. I'd like a lighter assembly than stock, but at the same time, don't want to pay $2k+. Don't need a ton of capacity; I run TT2/3 on a basically stock engine, so torque is < 380 at the wheels. The car pretty much only sees street driving if I'm testing repairs/mods, so street driveability is a secondary concern. Adding to the challenge is the fact I need to get everything replaced within two weeks, so probably means I'm looking for a complete balanced package (flywheel/PP/disc) off the shelf since I'll have limited ability to drive around town to machine shops getting stuff balanced with that turn-around time.
So, really looking for where the best, complete buy is. If I can get 80% of the performance of a 5.5", triple disc setup, but at 50% of the cost, I'd be very happy. Any help/advice is appreciated.
Most specifically, looking for opinions on optimum performance/$. I'd like a lighter assembly than stock, but at the same time, don't want to pay $2k+. Don't need a ton of capacity; I run TT2/3 on a basically stock engine, so torque is < 380 at the wheels. The car pretty much only sees street driving if I'm testing repairs/mods, so street driveability is a secondary concern. Adding to the challenge is the fact I need to get everything replaced within two weeks, so probably means I'm looking for a complete balanced package (flywheel/PP/disc) off the shelf since I'll have limited ability to drive around town to machine shops getting stuff balanced with that turn-around time.
So, really looking for where the best, complete buy is. If I can get 80% of the performance of a 5.5", triple disc setup, but at 50% of the cost, I'd be very happy. Any help/advice is appreciated.
01-25-2019, 11:27 PM
#2
Burning Brakes
In anticipation of needing a new clutch soon, I’ve done some research and settled on diamond stg1... stock-ish, but lighter billet steel fw with higher hp potential.
Best track option would be smaller dia, like 7.25” qm or triton but street/paddock drivability would suffer. And if no HP aspirations in future, stock ls6 would prob be very good low cost option. I’d shy away from aluminum fw though since heat could have an effect.
Best track option would be smaller dia, like 7.25” qm or triton but street/paddock drivability would suffer. And if no HP aspirations in future, stock ls6 would prob be very good low cost option. I’d shy away from aluminum fw though since heat could have an effect.
01-27-2019, 06:45 PM
#3
Safety Car
I have a Spec Stage 1 with aluminum fw and pp, 20# lighter than stock and very noticeable increase in acceleration. A little heavier than stock, but also a little more holding power. Lower MOI is easier on the syncros too. I recommend a new slave and remote bleeder line while you're in there. Don't forget to measure your clearances in case the slave needs shimmed.
01-28-2019, 12:49 AM
#4
Based on your use a stocker would be fine with zero issues. Clutch people are nuts. I have had more issues with quality clutch systems than just about anything else. Oem is a no brained. That’s what you need especially on a time crunch. I’m a racer and average a new clutch every 1 or 2 years so I have replaced them a lot.
01-28-2019, 01:42 AM
#5
In light of all the people reporting trouble with the clutch pedal stocking to the floor (myself included) I don't think oem is a good idea.
I have an RPS BC2, it drives great but I'm not sure I'd recommend it yet. I've got a funny noise that I think is coming from the clutch itself. Not sure yet though.
I have an RPS BC2, it drives great but I'm not sure I'd recommend it yet. I've got a funny noise that I think is coming from the clutch itself. Not sure yet though.
01-28-2019, 06:23 AM
#6
Appreciate the input.
I keep going back and forth between a QM 8.5” complete kit and just sticking with stock. Also seems my price objective is unrealistic unless sticking to stock, as replacing TOB and other stuff adds up quick. Given time crunch, needs to make a decision today to ensure I can get it in over the weekend.
Also have another, related question regarding dropping the driveline. Manual says drop and reinstall as one big chunk. However, I’m a bit concerned with reinstall trying to maneuver the TT attached to the trans. How do I separate the TT from trans while in the car? Simple as removing the shifter bolts in the tunnel prior to dropping?
I keep going back and forth between a QM 8.5” complete kit and just sticking with stock. Also seems my price objective is unrealistic unless sticking to stock, as replacing TOB and other stuff adds up quick. Given time crunch, needs to make a decision today to ensure I can get it in over the weekend.
Also have another, related question regarding dropping the driveline. Manual says drop and reinstall as one big chunk. However, I’m a bit concerned with reinstall trying to maneuver the TT attached to the trans. How do I separate the TT from trans while in the car? Simple as removing the shifter bolts in the tunnel prior to dropping?
01-28-2019, 11:16 AM
#7
Burning Brakes
I have a centerforce clutch and flywheel and couldn’t be happier. It’s lighter than stock, but takeoff is like stock and have had zero issues or problems. Definitely worth a look.
Other than that, stock seems like a great option.
Look at getting the quartermaster billet bearing sleeve for the slave cylinder to replace the plastic one. And a remote clutch bleeder, too.
Other than that, stock seems like a great option.
Look at getting the quartermaster billet bearing sleeve for the slave cylinder to replace the plastic one. And a remote clutch bleeder, too.
01-28-2019, 02:29 PM
#8
I've running an oem clutch and putting down similar torque numbers as you. I initially had the sticky clutch pedal and my temporary fix was with a tick master cylinder. Eventually when the clutch was swapped out, a new slave cylinder got rid of the sticky pedal for good. Also installed a remote bleeder for the slave cylinder and i bleed it after each event. I did inquire about an after market setup with a FW but was advised to stick with an oem setup for my use.
Last edited by DK83; 01-28-2019 at 02:30 PM.
01-28-2019, 04:35 PM
#9
Drifting
I dropped in one piece (even left the rear subframe attached). I separated the TT to service and reinstalled the TT separate from the trans/diff/subframe. Went together very easy!
Also have another, related question regarding dropping the driveline. Manual says drop and reinstall as one big chunk. However, I’m a bit concerned with reinstall trying to maneuver the TT attached to the trans. How do I separate the TT from trans while in the car? Simple as removing the shifter bolts in the tunnel prior to dropping?
Also have another, related question regarding dropping the driveline. Manual says drop and reinstall as one big chunk. However, I’m a bit concerned with reinstall trying to maneuver the TT attached to the trans. How do I separate the TT from trans while in the car? Simple as removing the shifter bolts in the tunnel prior to dropping?
02-20-2019, 10:21 AM
#10
Following up on this, ended up going with a QM 8.5” (https://www.quartermasterusa.com/pro...clutch-kit-8-5). Engagement is pretty aggressive, but not impossible. Definitely feel the reduced weight; shifting much more immediate over stock setup.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
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Miguel S (02-20-2019)
02-20-2019, 11:58 AM
#11
Safety Car
I think the price point and requirements are unrealistic given the corvette tax.
Contact Danny Popp for opinions given your situation, he may be able to help under the time crunch.
Contact Danny Popp for opinions given your situation, he may be able to help under the time crunch.
02-20-2019, 12:59 PM
#12
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St. Jude Donor '08
Following up on this, ended up going with a QM 8.5” (https://www.quartermasterusa.com/pro...clutch-kit-8-5). Engagement is pretty aggressive, but not impossible. Definitely feel the reduced weight; shifting much more immediate over stock setup.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
Just make sure to winch the car on your trailer if at all possible. Slipping them when loading creates more wear in 30 seconds than a weekend of road racing.
02-21-2019, 12:07 AM
#13
Safety Car
Following up on this, ended up going with a QM 8.5” (https://www.quartermasterusa.com/pro...clutch-kit-8-5). Engagement is pretty aggressive, but not impossible. Definitely feel the reduced weight; shifting much more immediate over stock setup.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
One question for those with these types of clutches. Do you expect an increase in vibration at idle? I expected to hear some “chatter” at idle in neutral, but I also do feel some pulsation in the clutch pedal. QM told me no balancing was necessary, so I just threw it in. Don’t sense any unreasonable vibration once in gear and moving.
