Driveline Upgrades
Thread Starter
Heel & Toe
Joined: Nov 2018
Posts: 15
Likes: 1
From: Cincinnati Ohio
Driveline Upgrades
Hey all, first drag strip pass yesterday, 12.6 @114mph with a terrible 2.1 60'. Went to make another pass and that ended up in failure with a slipping clutch. Car still drives fine on the street, but now that the clutch is slipping at higher power levels, it's only a matter of time before it becomes undriveable. I have spent all day reading older threads on driveline components, but with this being my first RWD car I still have a bunch of questions, mainly wondering what else besides the clutch I should upgrade.
Car is cam only, made 382whp and I daily drive it. I would like to hit the track every now and then, and would really like to see an 11.9 on street tires once I learn to properly launch. At a MINIMUM I'll be replacing the clutch, pressure plate, flywheel, throwout bearing, release bearing, slave cylinder, and install a remote bleeder. Looking at one of monster clutches single disk kits.
My confusion starts with the flywheel, is a lightweight flywheel beneficial, or will it just make the car a hassle on the street? Once I upgrade the clutch what am I going to break next? Seems like the weak points are the diff case and left axle shaft. At my relatively low power level, assuming I can get a good hook at the track, am I in danger of breaking these components? And if I am would it be a good idea to use the clutch install as a point to install a transmission brace or aftermarket transmission mount?
In the future I may replace the heads, or add a small nitrous shot, but really don't see myself adding too much power as I mainly want this car to be a fun reliable street car. Any help or opinions are appreciated!
Car is cam only, made 382whp and I daily drive it. I would like to hit the track every now and then, and would really like to see an 11.9 on street tires once I learn to properly launch. At a MINIMUM I'll be replacing the clutch, pressure plate, flywheel, throwout bearing, release bearing, slave cylinder, and install a remote bleeder. Looking at one of monster clutches single disk kits.
My confusion starts with the flywheel, is a lightweight flywheel beneficial, or will it just make the car a hassle on the street? Once I upgrade the clutch what am I going to break next? Seems like the weak points are the diff case and left axle shaft. At my relatively low power level, assuming I can get a good hook at the track, am I in danger of breaking these components? And if I am would it be a good idea to use the clutch install as a point to install a transmission brace or aftermarket transmission mount?
In the future I may replace the heads, or add a small nitrous shot, but really don't see myself adding too much power as I mainly want this car to be a fun reliable street car. Any help or opinions are appreciated!
Melting Slicks
Joined: Feb 2001
Posts: 2,803
Likes: 358
From: Northville, MI
Since you are in Cincinnati you should get in contact with Danny Popp, I believe he still is at McClusky Chevy, he is one of a handful of people who are experts on the C5 Corvette. He will also be able to do the installation. More than likely he would include a new pilot bearing and torque tube bushings. While you have the drive line out it might also be a good time to look at the trans output shaft and make sure it is straight. Especial if you are going to use drag radials in the future you might want to have a hardened output shaft installed.
Last edited by Gordy M; Mar 26, 2019 at 10:02 AM.
Drifting
Joined: Jul 2015
Posts: 1,844
Likes: 375
From: San Jose, CA
Release bearing is the same as throw-out bearing. It's the one that gets pushed, from the action of your pedal, against the pressure plate fingers to force the clutch to disengage.
My experience with a lightened flywheel is this: you can go too light, and you will hate driving it on the street. However, the stock clutch is too heavy for my tastes. If you cut, say, 10%, 15% ... even 25% off the weight of the stock clutch, you are likely to be happy after you get used to it. 10% will feel better but you get used to it in three minutes; 25% will take a bit more getting used to. Realistically, you can go down to, eh, probably 18 pounds before you really have to adjust your driving habits much more than what'll take a day or three to get used to it again.
Personally for your power level I might recommend an LS6 clutch with a lighter flywheel. A monster setup can do you fine too. Make sure, absolutely make sure, to balance any setup you get from monster.
Be honest with your goals today and in the future. No point installing, say, an LS6 clutch today and adding a 250 shot of nitrous tomorrow. But also no point spending $1000 on a clutch kit to hold 700 lb-ft of torque and then never add more power than you already have. Better to do the latter than the former, but best to get the kit that's just right for your application.
If you are drag-racing your car, well, the rear driveline has to come down to do a clutch, so install a trans/diff brace. Also, strongly consider changing out the motor mounts - the only available replacements, really, are ones that are harsher on the street but better on the strip.
Beyond that, you are not really likely to break _much_ on the strip at your power level. Stuff does inevitably break, especially if you run a grabby clutch and super sticky tires on a prepped surface ... but it'll be okay.
Don't forget to change out the prop shaft couplers and bearings (usually referred to as torque tube couplers and bearings.) I recommend OEM components, not super cheap.
My experience with a lightened flywheel is this: you can go too light, and you will hate driving it on the street. However, the stock clutch is too heavy for my tastes. If you cut, say, 10%, 15% ... even 25% off the weight of the stock clutch, you are likely to be happy after you get used to it. 10% will feel better but you get used to it in three minutes; 25% will take a bit more getting used to. Realistically, you can go down to, eh, probably 18 pounds before you really have to adjust your driving habits much more than what'll take a day or three to get used to it again.
Personally for your power level I might recommend an LS6 clutch with a lighter flywheel. A monster setup can do you fine too. Make sure, absolutely make sure, to balance any setup you get from monster.
Be honest with your goals today and in the future. No point installing, say, an LS6 clutch today and adding a 250 shot of nitrous tomorrow. But also no point spending $1000 on a clutch kit to hold 700 lb-ft of torque and then never add more power than you already have. Better to do the latter than the former, but best to get the kit that's just right for your application.
If you are drag-racing your car, well, the rear driveline has to come down to do a clutch, so install a trans/diff brace. Also, strongly consider changing out the motor mounts - the only available replacements, really, are ones that are harsher on the street but better on the strip.
Beyond that, you are not really likely to break _much_ on the strip at your power level. Stuff does inevitably break, especially if you run a grabby clutch and super sticky tires on a prepped surface ... but it'll be okay.
Don't forget to change out the prop shaft couplers and bearings (usually referred to as torque tube couplers and bearings.) I recommend OEM components, not super cheap.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
LIGHT FLYWHEELS are great for a car that you don't drive on the street a lot. I have a SPEC Twin Disk and it has much less MASS than a regular clutch. It revs fantastic BUT, you loose some street manners. The engine sometimes feels like it has a miss but it doesn't miss and the lighter the fly wheel, it can effect idle quality and low speed take offs. Especially if you have an aggressive cam. The flywheel gives the engine the inertia that it need to run smooth. You loose some of that inertia with a light flywheel.
I've learned to live with it. Car makes excellent power and runs well.
You MUST install a new PILOT BEARING!!! SHAME ON YOU if you don't! You really should do the critical slave cylinder shim measurements and install the correct size shim between the slave cylinder and the TT to obtain the correct air gap measurements between the throw out bearing and clutch pressure fingers.
You also need to consider your OEM FLYWHEEL FACTORY BALANCE vs the new pressure plate/flywheel balance. Get it wrong and you will have a mid RPM RANGE (1500-3500 RPM) VIBRATION that will drive you crazy! I match balance my new flywheel pressure plate to the Old OEM flywheel /pressure plate.
Consider up-grading the differential guts to C6 ZO6 parts. Output shafts, limited slip clutches, Belleville springs Much more reliable unit. Easy swap while its out! At least replace the output shaft seals!!!!!!
Consider a new clutch master cylinder. They do get crapped up inside and loose volume and reliability.
Bill
I've learned to live with it. Car makes excellent power and runs well.
You MUST install a new PILOT BEARING!!! SHAME ON YOU if you don't! You really should do the critical slave cylinder shim measurements and install the correct size shim between the slave cylinder and the TT to obtain the correct air gap measurements between the throw out bearing and clutch pressure fingers.
You also need to consider your OEM FLYWHEEL FACTORY BALANCE vs the new pressure plate/flywheel balance. Get it wrong and you will have a mid RPM RANGE (1500-3500 RPM) VIBRATION that will drive you crazy! I match balance my new flywheel pressure plate to the Old OEM flywheel /pressure plate.
Consider up-grading the differential guts to C6 ZO6 parts. Output shafts, limited slip clutches, Belleville springs Much more reliable unit. Easy swap while its out! At least replace the output shaft seals!!!!!!
Consider a new clutch master cylinder. They do get crapped up inside and loose volume and reliability.
Bill
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Release bearing is the same as throw-out bearing. It's the one that gets pushed, from the action of your pedal, against the pressure plate fingers to force the clutch to disengage.
My experience with a lightened flywheel is this: you can go too light, and you will hate driving it on the street. However, the stock clutch is too heavy for my tastes. If you cut, say, 10%, 15% ... even 25% off the weight of the stock clutch, you are likely to be happy after you get used to it. 10% will feel better but you get used to it in three minutes; 25% will take a bit more getting used to. Realistically, you can go down to, eh, probably 18 pounds before you really have to adjust your driving habits much more than what'll take a day or three to get used to it again.
Personally for your power level I might recommend an LS6 clutch with a lighter flywheel. A monster setup can do you fine too. Make sure, absolutely make sure, to balance any setup you get from monster.
Be honest with your goals today and in the future. No point installing, say, an LS6 clutch today and adding a 250 shot of nitrous tomorrow. But also no point spending $1000 on a clutch kit to hold 700 lb-ft of torque and then never add more power than you already have. Better to do the latter than the former, but best to get the kit that's just right for your application.
If you are drag-racing your car, well, the rear driveline has to come down to do a clutch, so install a trans/diff brace. Also, strongly consider changing out the motor mounts - the only available replacements, really, are ones that are harsher on the street but better on the strip.
Beyond that, you are not really likely to break _much_ on the strip at your power level. Stuff does inevitably break, especially if you run a grabby clutch and super sticky tires on a prepped surface ... but it'll be okay.
Don't forget to change out the prop shaft couplers and bearings (usually referred to as torque tube couplers and bearings.) I recommend OEM components, not super cheap.
My experience with a lightened flywheel is this: you can go too light, and you will hate driving it on the street. However, the stock clutch is too heavy for my tastes. If you cut, say, 10%, 15% ... even 25% off the weight of the stock clutch, you are likely to be happy after you get used to it. 10% will feel better but you get used to it in three minutes; 25% will take a bit more getting used to. Realistically, you can go down to, eh, probably 18 pounds before you really have to adjust your driving habits much more than what'll take a day or three to get used to it again.
Personally for your power level I might recommend an LS6 clutch with a lighter flywheel. A monster setup can do you fine too. Make sure, absolutely make sure, to balance any setup you get from monster.
Be honest with your goals today and in the future. No point installing, say, an LS6 clutch today and adding a 250 shot of nitrous tomorrow. But also no point spending $1000 on a clutch kit to hold 700 lb-ft of torque and then never add more power than you already have. Better to do the latter than the former, but best to get the kit that's just right for your application.
If you are drag-racing your car, well, the rear driveline has to come down to do a clutch, so install a trans/diff brace. Also, strongly consider changing out the motor mounts - the only available replacements, really, are ones that are harsher on the street but better on the strip.
Beyond that, you are not really likely to break _much_ on the strip at your power level. Stuff does inevitably break, especially if you run a grabby clutch and super sticky tires on a prepped surface ... but it'll be okay.
Don't forget to change out the prop shaft couplers and bearings (usually referred to as torque tube couplers and bearings.) I recommend OEM components, not super cheap.
100% on the mark!Bill
Racer
Joined: Jul 2015
Posts: 420
Likes: 17
From: Helotes Satx
Hey buddy I just want to give you my opinion based of of my real world experience. When it comes to clutches make sure the clutch is light like the stock ls6, ls7 is heavy and will I mean will also you down at the track! So many have in installed and liked its clamping force and strength for basic na applications but hated it cause they can almost tell its immediate heaviness. My car has the McLeod RxT. I've helped install 3 RsT by McLeod and is my go to clutch recommendation, just take the stock flywheel to the local machine shop and spend $20-40 and have it turned. I have installed 1 spec 3+ not the 3 but the 3+ the 3 is a puck clutch and kinda a on off clutch driveability sucked. The 3plus is very nice but for 150$ you can have a twin disc that has more than enough strength for a built na car or stroker na and a shot or a simple boosted ls1/6. I have pulled the vette drivetrain more than enough times on my garage floor or buddies garage floor it is a simple science for me now and can almost 100% coach it over the phone and can go from rolling on the floor to in the air and the torque tube out in 1.5hrs.
Here is my next serious recommendation I mean serious. If this is a fun toy and you dont mind sometimes breaking somthing because you wanna play hard ie.. you have to play to pay. Do not put stronger stub shafts in the rear end I repeat do not!!! I've spent to much money on braking to next part. The c6z shafts are strong some will say stronger than the 300m and others. The reason I say dont upgrade is for this reason. Your car will find the next weakest link. The diff case can/will crack, the pinion support can/will crack, the trans mainshaft can/will crack. I broke 1 diff after c6z shafts install. The diff cracked and the pinion support cracked then took out the mainshaft. So I found a used c5z diff for 500$ keep in mind that this was a c5z diff that broke. Then I put a stock 27spline mainshaft in which was $200used in great shape inspected by the best Texas vette drivetrain builder, most guys charge 200-400 just to swap the main shafts. I had the trans rebuilt with upgraded keys and pads and new syncros and a slider assembly or two. Wanted a new trans since it was out again and figured few owners wouldn't hurt. Wow is all I could say it was smooth as butter. Back to the track I went lol. More drivetrain shake and BAM broke again. Man them c6z shafts are strong!!! Snapped the mainshaft again and cracked 2 ears off the pinion support. I ordered a 30spline mainshaft from thegearbox.com, picked up another c5z diff and had the pinion gear machined for the 30spline mainshaft for the trans. Picked up the c6 or c6z I can't remember pinion support which is way larger than the c5 pinion support had that installed and properly shim along with the 30spline mainshaft in the trans. No I'm thinking alright I've got what rpm calls a stg 5 or 6 trans and a badA diff. Installed a cage and diff mount. Lasted 5months and snapped the 30spline mainshaft but everything else was intact. No my power level does not matter. Stock can break upgrades and high hp cars can run stock parts. All depends on driver and left and right foot!!!!!!!!
Moral of what I'm telling you is if I would have installed a nice diff mount and learn to watch for shake and keep my release foot slower I fell I would have been ok. KEEP THE STOCK OUTPUT SHAFTS FOR 1 REASON, THEY DIRT CHEAP AND CAN REPLACE YOURSELF VERY VERY EASY AND FAST! BEEF UP THAT WEAK LINK AND THE NEXT WEAK THING WILL BREAK. Big money for the business that do the work so keep it simple and work on driving skills.
Now I have a c6z drivetrain in my current 01z. With a c6 base long stub shaft for if/when I snap it!!! Lol lol. I can call my ins comp tow me home have the diff out and long shaft installed and diff back in and on the ground in 2-3hrs. And save so much money!!!
On your car I would recommend a rst clutch. Get some used 799/243 heads off of clist/fb have them rebuilt and milled and either bowl and valve job or full port. With a used fast and run your 11s on street tires. Then when you want more install a small shot or then sell your heads and intake and install some stock 317 heads and a ecs/a&a kit and make 600rw.
But enjoy the car!!! Good luck
Here is my next serious recommendation I mean serious. If this is a fun toy and you dont mind sometimes breaking somthing because you wanna play hard ie.. you have to play to pay. Do not put stronger stub shafts in the rear end I repeat do not!!! I've spent to much money on braking to next part. The c6z shafts are strong some will say stronger than the 300m and others. The reason I say dont upgrade is for this reason. Your car will find the next weakest link. The diff case can/will crack, the pinion support can/will crack, the trans mainshaft can/will crack. I broke 1 diff after c6z shafts install. The diff cracked and the pinion support cracked then took out the mainshaft. So I found a used c5z diff for 500$ keep in mind that this was a c5z diff that broke. Then I put a stock 27spline mainshaft in which was $200used in great shape inspected by the best Texas vette drivetrain builder, most guys charge 200-400 just to swap the main shafts. I had the trans rebuilt with upgraded keys and pads and new syncros and a slider assembly or two. Wanted a new trans since it was out again and figured few owners wouldn't hurt. Wow is all I could say it was smooth as butter. Back to the track I went lol. More drivetrain shake and BAM broke again. Man them c6z shafts are strong!!! Snapped the mainshaft again and cracked 2 ears off the pinion support. I ordered a 30spline mainshaft from thegearbox.com, picked up another c5z diff and had the pinion gear machined for the 30spline mainshaft for the trans. Picked up the c6 or c6z I can't remember pinion support which is way larger than the c5 pinion support had that installed and properly shim along with the 30spline mainshaft in the trans. No I'm thinking alright I've got what rpm calls a stg 5 or 6 trans and a badA diff. Installed a cage and diff mount. Lasted 5months and snapped the 30spline mainshaft but everything else was intact. No my power level does not matter. Stock can break upgrades and high hp cars can run stock parts. All depends on driver and left and right foot!!!!!!!!
Moral of what I'm telling you is if I would have installed a nice diff mount and learn to watch for shake and keep my release foot slower I fell I would have been ok. KEEP THE STOCK OUTPUT SHAFTS FOR 1 REASON, THEY DIRT CHEAP AND CAN REPLACE YOURSELF VERY VERY EASY AND FAST! BEEF UP THAT WEAK LINK AND THE NEXT WEAK THING WILL BREAK. Big money for the business that do the work so keep it simple and work on driving skills.
Now I have a c6z drivetrain in my current 01z. With a c6 base long stub shaft for if/when I snap it!!! Lol lol. I can call my ins comp tow me home have the diff out and long shaft installed and diff back in and on the ground in 2-3hrs. And save so much money!!!
On your car I would recommend a rst clutch. Get some used 799/243 heads off of clist/fb have them rebuilt and milled and either bowl and valve job or full port. With a used fast and run your 11s on street tires. Then when you want more install a small shot or then sell your heads and intake and install some stock 317 heads and a ecs/a&a kit and make 600rw.
But enjoy the car!!! Good luck
