Transmission Recommendations
01-18-2009, 05:49 PM
#1
Transmission Recommendations
I'm pushing 38000 miles and more than 30 HPDE days and the clutch seems to be in need of replacing. I'm not noticing any slip yet, but I've got occasional screetching in 5/6th gears coming from clutch area plus the tranny engages with the clutch almost fully out. So, I'm guessing before I get into next season that I need to have it addressed.
I've heard that aftermarket clutches may not be worth it - not ready for prime time and require shims and such. I would, however, like to beef up the drivetrain to help it wear better/longer.
Anyone have recommendations on what I could do to achieve my goal with a minimum of compromise (i.e., issues that I didn't know would occur)? New tranny? Bullet proof clutch?
I've heard that aftermarket clutches may not be worth it - not ready for prime time and require shims and such. I would, however, like to beef up the drivetrain to help it wear better/longer.
Anyone have recommendations on what I could do to achieve my goal with a minimum of compromise (i.e., issues that I didn't know would occur)? New tranny? Bullet proof clutch?
01-18-2009, 07:04 PM
#3
Racer
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Call RPM and talk to them about your goals regarding the transmission. I had a Level V with mechanical cooler installed when mine went out. Only have a few track miles on it. Clutch if you are not putting over 500 hp to the wheels consider an LS7 clutch and install a remote bleeder regardless of the clutch you decide. I also run an LS7 in my '02 ZO6 feels great!
01-18-2009, 07:16 PM
#4
"AlohaC5" Senior Member
01-18-2009, 08:28 PM
#5
Instructor
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RPM Level 5 has been very good for me when it comes to transmission/differential, and held up wonderfully to 25 straight hours of racing. When they opened it up, it was still in very good condition.
Exedy twin disk was great for 60+ race hours, with the last 25 being at the 25 Hours of Thunderhill '07, and still was good when we took it out.
Steve
Exedy twin disk was great for 60+ race hours, with the last 25 being at the 25 Hours of Thunderhill '07, and still was good when we took it out.
Steve
01-20-2009, 01:43 PM
#6
So I'll see what RPM has to say, thanks! What is the importance of a remote bleeder valve? Also, will the RPM twin disk give me the same pedal feel and operation that I'm used to with greater performance and longevity?
01-20-2009, 02:20 PM
#9
Racer
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When the fluid gets dark and dirty it causes problems like sticking clutch pedal or under WOT the clutch will stay on the floor. Bad things happen once the fluid gets dark. Makes flushing the entire clutch system easier. You can turkey baste it out but it does take longer. For less than $100 bucks for a remote bleeder just makes the overall process easier.
01-20-2009, 06:51 PM
#10
Melting Slicks
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RPM Level V Transmission and an RPS Twin Friction Clutch (if money is no object - no compromise) - then the RPS Street Twin Carbon Clutch.
The RPS street twin is a great clutch, the pricing has come down recently and it is a very streetable clutch that can handle a bunch of power. I've sampled several twins and this is by far the best!!
01-21-2009, 09:29 AM
#12
Racer
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are you running more than stock power?? if not, I would go back with stock clutch. no reason to pay for something you dont need. do you change your fluids regularly???? I change my trans fluid after 2 race weekend. change fluid in clutch res. I myself have upgraded trans and clutch, i also have over 550 hp, and spray nos. ..... If the stock cluth lasted this long, go with another one,
I'm pushing 38000 miles and more than 30 HPDE days and the clutch seems to be in need of replacing. I'm not noticing any slip yet, but I've got occasional screetching in 5/6th gears coming from clutch area plus the tranny engages with the clutch almost fully out. So, I'm guessing before I get into next season that I need to have it addressed.
I've heard that aftermarket clutches may not be worth it - not ready for prime time and require shims and such. I would, however, like to beef up the drivetrain to help it wear better/longer.
Anyone have recommendations on what I could do to achieve my goal with a minimum of compromise (i.e., issues that I didn't know would occur)? New tranny? Bullet proof clutch?
I've heard that aftermarket clutches may not be worth it - not ready for prime time and require shims and such. I would, however, like to beef up the drivetrain to help it wear better/longer.
Anyone have recommendations on what I could do to achieve my goal with a minimum of compromise (i.e., issues that I didn't know would occur)? New tranny? Bullet proof clutch?
01-21-2009, 10:11 AM
#13
Former Vendor
We use the twin disk RPS also. It's been damn good. Slighting heavy of a peddle effort, but not hard to push in and out. The stock one feels like a limp noddle anyways.
Randy
Randy
01-21-2009, 03:02 PM
#14
Team Owner
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St. Jude Donor '05-'08
We use the rps twin. I have it in my car and really like it. It probably overkill for a lower hp car. We also have good results with the single tex on our lower hp cars.
01-21-2009, 05:59 PM
#15
Drifting
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I have stock HP engine. I use a Fidanza Aluminum Flywheel and a SPEC level 1 clutch disc and aluminum pressure plate. Huge reduction in rotating mass and feels almost like stock. A little firmer but easy to drive. Thottle response is fantastic and rev matching is easy.
Order the Aluminum Pressure plate not the "Light-weight" one which is just a lighter version of the regular pressure plate.
You can even save another pound or so by using the level 3 clutch.
Order the Aluminum Pressure plate not the "Light-weight" one which is just a lighter version of the regular pressure plate.
You can even save another pound or so by using the level 3 clutch.
01-21-2009, 08:44 PM
#17
how does fresh clutch fluid keep the clutch from slipping? or did you mean is that fresh clutch fluid keep your clutch operating correctly.
01-30-2009, 08:09 PM
#18
So while someone has my drivetrain removed, should I be doing anything else during the clutch replacement? If I stick with OEM, what comes with the correct GM part? For that matter, does anyone have the proper part number so I can shop around?
01-30-2009, 10:54 PM
#19
Drifting
www.gmpartshouse.com
Look up his posts for monthly specials, always has the LS7 clutch listed. Pretty good prices and a good guy to work with.
Water, in the form of humidity gets into the clutch fluid. When enough gets in it will boil at a much lower temp, which you can easily reach on the track. Then you won't be able to do much with it. Flushing regularly will keep the water content very low and keep the boiling temp high enough so it does not boil. Someone can correct me if I'm wrong, but one of the symptoms of boiled fluid is a slipping clutch, the reason being that it is not really much of a hydraulic system at that point. Once boiling occurs you have a steam pocket (probably a lot of very small ones) which is compressible instead of fluid which is not. So, when you press the pedal the clutch does not fully disengage, because some of the pressure is compressing the steam and not moving the slave. So when you shift it may not fully disengage, and cause some glazing of the clutch. At least thats how I see it, and I could be wrong...
Look up his posts for monthly specials, always has the LS7 clutch listed. Pretty good prices and a good guy to work with.
Water, in the form of humidity gets into the clutch fluid. When enough gets in it will boil at a much lower temp, which you can easily reach on the track. Then you won't be able to do much with it. Flushing regularly will keep the water content very low and keep the boiling temp high enough so it does not boil. Someone can correct me if I'm wrong, but one of the symptoms of boiled fluid is a slipping clutch, the reason being that it is not really much of a hydraulic system at that point. Once boiling occurs you have a steam pocket (probably a lot of very small ones) which is compressible instead of fluid which is not. So, when you press the pedal the clutch does not fully disengage, because some of the pressure is compressing the steam and not moving the slave. So when you shift it may not fully disengage, and cause some glazing of the clutch. At least thats how I see it, and I could be wrong...
02-03-2009, 04:42 PM
#20
www.gmpartshouse.com
Look up his posts for monthly specials, always has the LS7 clutch listed. Pretty good prices and a good guy to work with.
Water, in the form of humidity gets into the clutch fluid. When enough gets in it will boil at a much lower temp, which you can easily reach on the track. Then you won't be able to do much with it. Flushing regularly will keep the water content very low and keep the boiling temp high enough so it does not boil. Someone can correct me if I'm wrong, but one of the symptoms of boiled fluid is a slipping clutch, the reason being that it is not really much of a hydraulic system at that point. Once boiling occurs you have a steam pocket (probably a lot of very small ones) which is compressible instead of fluid which is not. So, when you press the pedal the clutch does not fully disengage, because some of the pressure is compressing the steam and not moving the slave. So when you shift it may not fully disengage, and cause some glazing of the clutch. At least thats how I see it, and I could be wrong...
Look up his posts for monthly specials, always has the LS7 clutch listed. Pretty good prices and a good guy to work with.
Water, in the form of humidity gets into the clutch fluid. When enough gets in it will boil at a much lower temp, which you can easily reach on the track. Then you won't be able to do much with it. Flushing regularly will keep the water content very low and keep the boiling temp high enough so it does not boil. Someone can correct me if I'm wrong, but one of the symptoms of boiled fluid is a slipping clutch, the reason being that it is not really much of a hydraulic system at that point. Once boiling occurs you have a steam pocket (probably a lot of very small ones) which is compressible instead of fluid which is not. So, when you press the pedal the clutch does not fully disengage, because some of the pressure is compressing the steam and not moving the slave. So when you shift it may not fully disengage, and cause some glazing of the clutch. At least thats how I see it, and I could be wrong...