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Jeff20B · 01-17-2009, 06:18 PM

I've given it some thought and I think I'll go with the Racing Beat SS 225mm pressure plate because, as you said, it's a 3/4 ton truck and needs a stronger pressure plate than say a small coupe; also it needs good grip at a low RPM so centerforce is out. The RB SS pressure plate will mimic the decent grip of a stock REPU pressure plate. Pedal effort is also acceptable to me. It feels fine in my friend's REPU with the same pressure plate.

The flywheel is going to be a Racing Beat light steel. I'd have gone with a GSL-SE flywheel if NA, but since I'm going with a 5" SC, I feel the reduced weight of the flywheel will be made up for with the extra rotational weight and drag of the SC. Besides my friend's REPU does well enough with the same flywheel.

The one and only question I have for you is about the clutch disc itself. My two choices are an HD 225mm and a stock 225mm. You said something about using an HD disc and to put up with the shuddering. It shudders because it has no springy marcels between friction surfaces. However it is plenty strong enough to handle towing and other heavy duty use in an REPU. My only gripe, I guess, is that it might shudder from time to time.

Now we take a look at a stock disc. It's one of those common '83-'92 Daikin discs with the rubber spings (sprung center) and springy marcels. This disc has a lot of buffer. I put one in my '76 Cosmo with a GSL-SE flywheel and the silly disc seems to take forever to grab. It's not an issue of grip, because it has plenty to spin the rear tires, but what I'm taking about is how long the "buffer zone" is while you're letting the clutch pedal out. If I had the engine or tranny out right now I'd have swapped in an HD disc because I'm really not very happy with the long friction point of this type of disc after having driven HD discs for any length of time. It's smooth as silk though, which I must admit does suit the character of the Cosmo. I could get used to it.

So what's the question then? Well, we know the pedal travel of an REPU is shorter than a Cosmo or 1st gen, and we know a stock REPU disc does have marcels between disc friction surfaces. I was merely wondering whether a stock Daikin disc, with its wide friction point would suit the REPU better than an HD disc. I'm starting to think no it wouldn't. The way I see it, the Daikin disc is lightest duty or stock duty (I've seen the aftermath of one used really harshly in some guy's FC; the rubber spring things popped out of the center lol), the REPU stock disc is probably closer to heavy duty like the HD, but with marcels helping to add buffer. Then finally the HD is, I guess should be considered extreme duty as far as 225mm organic friction type discs go. To get anything stronger or more reliable you'd need a solid center, and there goes the rest of your buffer. I don't know of any discs like that and I certainly won't use a puck disc in the truck.

Wow, just having a chance to type it all out has helped a lot. I now know that I'll be best off using the HD disc in the REPU. If it shudders a little on take off, who cares? I'll be employing two competition motor mounts to help steady the engine if and when it shudders, to help minimize the effects.

All three clutch components are either brand new, hardly used (less than 5 miles) or in the case of the flywheel, less than 200 miles. I'll scuff it up just to be sure the disc breaks in on a roughened surface. This should help prevent the conditions which produce shuddering from even begining.

Thanks Dave.

01-17-2009, 06:18 PM	#40
Jeff20B Rotary Fanatic Join Date: Mar 2008 Posts: 215 Rep Power: 18	I've given it some thought and I think I'll go with the Racing Beat SS 225mm pressure plate because, as you said, it's a 3/4 ton truck and needs a stronger pressure plate than say a small coupe; also it needs good grip at a low RPM so centerforce is out. The RB SS pressure plate will mimic the decent grip of a stock REPU pressure plate. Pedal effort is also acceptable to me. It feels fine in my friend's REPU with the same pressure plate. The flywheel is going to be a Racing Beat light steel. I'd have gone with a GSL-SE flywheel if NA, but since I'm going with a 5" SC, I feel the reduced weight of the flywheel will be made up for with the extra rotational weight and drag of the SC. Besides my friend's REPU does well enough with the same flywheel. The one and only question I have for you is about the clutch disc itself. My two choices are an HD 225mm and a stock 225mm. You said something about using an HD disc and to put up with the shuddering. It shudders because it has no springy marcels between friction surfaces. However it is plenty strong enough to handle towing and other heavy duty use in an REPU. My only gripe, I guess, is that it might shudder from time to time. Now we take a look at a stock disc. It's one of those common '83-'92 Daikin discs with the rubber spings (sprung center) and springy marcels. This disc has a lot of buffer. I put one in my '76 Cosmo with a GSL-SE flywheel and the silly disc seems to take forever to grab. It's not an issue of grip, because it has plenty to spin the rear tires, but what I'm taking about is how long the "buffer zone" is while you're letting the clutch pedal out. If I had the engine or tranny out right now I'd have swapped in an HD disc because I'm really not very happy with the long friction point of this type of disc after having driven HD discs for any length of time. It's smooth as silk though, which I must admit does suit the character of the Cosmo. I could get used to it. So what's the question then? Well, we know the pedal travel of an REPU is shorter than a Cosmo or 1st gen, and we know a stock REPU disc does have marcels between disc friction surfaces. I was merely wondering whether a stock Daikin disc, with its wide friction point would suit the REPU better than an HD disc. I'm starting to think no it wouldn't. The way I see it, the Daikin disc is lightest duty or stock duty (I've seen the aftermath of one used really harshly in some guy's FC; the rubber spring things popped out of the center lol), the REPU stock disc is probably closer to heavy duty like the HD, but with marcels helping to add buffer. Then finally the HD is, I guess should be considered extreme duty as far as 225mm organic friction type discs go. To get anything stronger or more reliable you'd need a solid center, and there goes the rest of your buffer. I don't know of any discs like that and I certainly won't use a puck disc in the truck. Wow, just having a chance to type it all out has helped a lot. I now know that I'll be best off using the HD disc in the REPU. If it shudders a little on take off, who cares? I'll be employing two competition motor mounts to help steady the engine if and when it shudders, to help minimize the effects. All three clutch components are either brand new, hardly used (less than 5 miles) or in the case of the flywheel, less than 200 miles. I'll scuff it up just to be sure the disc breaks in on a roughened surface. This should help prevent the conditions which produce shuddering from even begining. Thanks Dave.