Question: Clutch Replacement

[Bolisk]

So collapsed my clutch last night. No amount of adjustment allows the clutch to work. Trans will shift with the car off. . .but when the car is running, I can not get the trans into any gear. I'm guessing the springs broke.

I have a 1970 Coupe 350/350, modified to pseudo LT-1 specs. So she puts on a good amount of horse power.

So I have some questions pertaining to replacing the clutch.

1) Do I have to re-surface the flywheel when changing the clutch?

2) What is the best Center-force clutch to use for an aggressively driven street car. Centerforce-I or II, or Dual Friction?

3) what are the normal componets that you replace when you replace your clutch? (other than pilot bearing, throwout bearing, and the clutch)

Thanks
JonR

 

[jims427400]

On my 68 last fall I also replaced the fork due to broken spring, changed the teeth ring on the flywheel( getting worn possibly the starter wasn't lined up properly)did resurface flywheel and new bronze pilot bushing.
good luck

 

[Hib Halverson]

(snip)
1) Do I have to re-surface the flywheel when changing the clutch?

It depends on how many miles are on the wheel since the last clutch change and on the condition of the flywhee's friction face, but generally, you surface the flywheel when you change a clutch.

2) What is the best Center-force clutch to use for an aggressively driven street car. Centerforce-I or II, or Dual Friction?

In my experience, McLeod is a better choice in clutches for that car. I have McLeod clutches in all three of my Corvettes and one of them, the clutch in my 71, has been in service for over 15 years. Their performance has been outstanding. As to what specific McLeod clutch to use, that depends on the torque output of the engine and how the car will be used.

3) what are the normal components that you replace when you replace your clutch? (other than pilot bearing, throwout bearing, and the clutch)

Well, again, it depends on mileage, but in addition to the pilot and the T.O. bearing, you want to inspect the clutch pivot ball and the clutch fork. If they are worn, I'd replace them, too.

 

[Crimson Thunder]

Whatever brand you decide to use,don't overclutch it. Your leg will get tired of driving a car with super-heavy clutch in traffic. I made this mistake years ago in my 75 V8 Monza.

 

[glen242]

I use a CF II with my non-stock 383.

I have been happy with it, for the last 4 years. No race just street.

 

[tracksnblades1]

I would recommend to verify balance of components before installing. Especially if any machine work is done to any part of the rotating assembly. There are Mondays and Fridays at clutch and flywheel shops too.

 

[Bolisk]

So ultimatly, I went with a Centerforce Dual Friction. Several friend have them and are happy. I've got the car all back together. . .and took it for a test drive.

Sadly. . .the car is nearly un-driveable. I don't know if I did something wrong. . .or if its a bad clutch adjustment. . .or if it's normal after a new clutch is installed.

1) when I first tested the car, I burned rubber at IDLE comming out of the garage. THe clutch just when from free to fully engaged in a hair trigger. Almost went flying into one of my parked other cars. So I figured I got the adjustment wrong. . .re-did it.

2) After the second adjustment.. .I cured the insto-grab. . .and was able to take it for a spin arround the block. Not sure I had the adjustment right again. . .and the clutch started to smell. Not sure if that is normal during first break in. . .or if the cluch was not fully dis-engaging.

3) Back to adjustment again. Called a buddy. . .got him to sit in the car, until it felt "right" but still had about 1 inch of free play. Haven't drove the car since. . .afraid it will kill me. Or I will burn out the new clutch.

So. . .I was trying my damnedest to have everything fixed by today. . .so I could take it to Bloomington Gold. . .but not sure the car will make the 40 mile trip . . . a little nervous.

Can anyone tell me what to expect within the first few miles of driving on a new clutch?

Thanks.
-Jon

 

[Bolisk]

Oh by the way. . .

Turns out I collapsed the diaphram on my old clutch. . .and litteraly blew the clutch disc apart! WONDERFULL!!!! The old clutch was an old asbestose Hays.

 

[c3vette]

Not sure about Centerforce twins, but I had installed A MCleod Street twin in my 94Z28 and it came pre setup with shims for correct clearance between the discs (which was critical). I expect Centerforce may be similar. I has engagement issues when I set mine up and after pulling it again, found the disc clearance was in-correct, because I had lost a shimnat some point. I also went with a New Flywheel.
I'd give Centerforce a call and explain your situation to them.

 

[Bolisk]

To close off this thread.

It took me three nights (7pm to 11pm) to get everything apart, and two nights to get everything back together.

I installed a centerforce dual friction clutch. At first I found this to be VERY touchy, but once I broke it in . . .it was indistinguishable from my origional clutch (from a pedal feel perspective). Very happy with the new clutch.

I did find that my car had the wrong length clutch fork pivot stud, which probably caused the failure in the first place.

-JR

 

[c3vette]

Good to hear!