I am planning a new clutch and have a few questions.

I want this car to be street comfortable and eliminated ceramic "Puck" type clutches to avoid the usual chatter. I am thinking either an organic disc or a carbon Kevlar as in most stage 2 clutches.

I have been looking into a few, and now wondering what the differences are between the C5 and C6 clutch. Is the Slave cylinder the only difference? Will a clutch with a C6 slave unit fit into a C5 car? Generally THE c6 Clutches are rated for higher torque capacity. This is probably the result of greater pressure applied to engage the clutch. I am considering clutches by several manufacturers but have narrowed my choices to PPC and XTR.

Both have clutches for C5 and C6. the differences seem to be higher torque capacity and the C6 has a heavier flywheel, 20 lbs. compared to the c5 AT 15 LBS. both are Forged one piece Chromoloy. I think the flywheels are interchangeable and I'd like the heavier flywheel because the car will be driven on the street and cruising down Gratiot Avenue during Cruise week and also the Woodward Avenue Cruise. These are the two largest automotive events in North America.

Since I may modify or replace the LS1, I'd like to install a clutch that will handle more torque. XTR is clutch kit PN XTR82058R1FX and PPC is either 382058cf or 3820581.

Are these good clutches to use now? What recommendations can you make?

 

For a street car, the heavier the flywheel the better its street manners are going to be.

Never heard of either of those 2 companies.

No real difference in the clutch assembly between a C5 and a C6 unless you are talking a LS9 clutch which has a different flywheel.

If you are looking for a decent price in a twin disc from a reputable manufacturer, the LS9 clutch is going to be the best option. If you are going to step up to an aftermarket clutch from a well known company you are not going to get by for cheap....Personally I prefer Monster clutches.

 

Thanks for your reply. I have the engine out of the car right now, so clutch choices are logical.

I am also checking ACT clutch kits and GM9 HDSS at $500 with 745 ft lbs of torque. The ACT Prolite flywheel is 14.6 lbs and the cost is $350. FX Racing also has a nice stage 2 clutch kit with a forged flywheel but very light at 15 lbs. Stock flywheel is about 23 lbs, so I am leaning towards the 20 lb F.W. that I see with many C6 clutch Kits. Not sure why C5 kits have lighter F.W.s.

If the slave cylinder and the release bearing are not an issue and will work in my C5 car, even though the clutch kit says it is for a C6 only. I may get this. My other choice is to stay with OEM type clutch and plan to replace it if I modify or replace the engine.

 

use what gets used a lot. very little experience anywhere on the web with the c5 and anything from ACT or the others you mention. ACT typically is a good company, but, more solid choices exist, the 3 i would look at are

1. the ls7 clutch from scoggin dicky with the ram aluminum flywheel. complete set is something like 580. this keeps the weight the same as stock. an iron ls7 flywheel adds about 10lbs

2. the monster level 1 or level 2

that's it. all of those fit, won't have weird clearance issues or anything else. no clutch with a 745lb rating, if it's a single disc will drive well. twins can be another story

 

Whatever clutch you use, you need to use the C5 slave cylinder. The C6 slave cylinder doesn't work in the C5.

 

Thanks John for the answer to my final question about the slave cylinder. I still had my doubts about whether the C6 Slave would work... which it evidently won't. It is difficult to compare pictures and some differences are cosmetic, so John helped with that info.

I am now considering using the OEM GM flywheel instead of ordering a Chromoloy FW. The OEM looks good to me and I save at least $100 by re-using it.

I suspect that higher torque ratings for C6 clutches are obtained by applying more pressure, and the need for a different slave cylinder. Different doesn't always mean it doesn't work, so I needed knowledgeable advice.

I've had several Corvairs stripped down to the bare chassis (Including Spyder and Corsa) but this is the first time for a Corvette. With a little help from my friends.

This is a Z19 Coupe with Z51 Sport package. Options are the GU6 3.42 Axle, LS1 5.7L Eng, FE3 H/D Susp, MM6 Manual Trans, NV7 Var Stg, XGG YGH QD4 WHEELS AND TIRES. And it is 7OU Torch Red, arguably the best color ever for a Corvette.

 

the car is stock? if it is you really don't need to go too crazy with the clutch

you easily could reuse your flywheel, order the ls6 pressure plate and disc and be good to go. would suggest having the machine shop balance your new plate to the same offset as the old one though. GM in final assembly counterbalanced some pressure plates and flywheels to decrease vibration in the drivetrain. what you do is take your old flywheel/plate out, mark TDC. have the machine shop spin it and note where it's xx grams out of balance, have the flywheel turned as little as possible or not at all if it's smooth and there's no hot spotting. then bolt on the ls6 pressure plate and set the balance offset to the same as your old combo

 

Thanks, I appreciate the good advice. I was coming to the same conclusion about using the old flywheel. But thinking of using a stage 2 clutch kit and they usually recommend replacing the flywheel with the clutch. An LS6 disc and plate are worth looking into. I want to get the engine installed soon after cleaning and repainting the frame etc. with satin black.

Another topic for long range plans. Someone told me that because there are few Z19s, I should keep it stock, but I am thinking the value wouldn't hurt by installing an LS3 or LS7 shortblock. I don't want to maximize HP, just increase reliability and torque. Can I use the LS1 heads, fuel injection, ignition coils, oil pan, water pump etc.?

 

the ls2 bolts up with ls1 or ls6 heads but the ls3 and ls7 do not.

the ls6 clutch is fine for a stock ls1 engine. if you plan on any mods you want to use a clutch that can handle them and that clutch really imo is good for about 375rwhp. guys have pushed more but they get sticky and start having issues. the ls7 clutch you can add 100hp onto that number. the ls7 clutch drives exactly like stock too. it will however require an ls7 flywheel and or the ram or fidanza ls7 flywheels

i'd figure out your mod plans before you buy a clutch. if it's staying stock the ls6 is fine. more than that, well, the clutch should match the power, tires and driving habits

 

Thanks Racebum. I had thought of the C6 clutch but not of the LS7 clutch. An LS3 or LS7 short block is a near future project, so I've been keeping this in mind for things like the clutch. I am not sure if the LS1 oil pan, injectors, and coil packs will work on an LS7. So I had put out the word that I was looking for an LS3 engine to use for parts on an LS3 or LS7 short block. Most yards rebuild or strip bad engines. No luck yet.

 

We do have all of our monster clutches on memorial weekend on sale for $125 off! Any level, any clutch! They work great and Monster is a stand up company. Let me know if we can be of more help!

Every clutch in the C6 cars (minus zr1) is the LS7 clutch...

 

I'd assume the flywheels are different weights in the C5 and C6 options because the stock clutches are of different weights from the factory in the C5 and C6. As far as them holding two different amounts of power, the slave cylinder will not change that though the diameter of the disc and pressure plate can. If you have any questions about a Monster Clutch, don't hesitate!

 

Thanks for all the information. I appreciate the advice. I'll check out the web links you provided also.