Clutch Thoughts

[yellow rose]

Ram and Sam want to make sure their clutch isn't the weak link. Whatever abuse you might throw at their clutch, if the transmission breaks instead it won't be their problem. Typical clutch customer wants a clutch that doesn't slip when they put the power to it, they don't understand that a clutch NEEDS to slip a little for the whole package to come together.

2600 is just too much clamp for a metallic disc behind a mild 383. It will be hard to launch, also hard on parts. Before the NMRA Coyote Stock guys discovered the ClutchTamer, they were all the way down to 1100-1500 lbs of diaphragm pp clamp using the same basic Ram 900 series disc that's used in the Powergrip HD. They run 10.0's @ 3175lbs.

Those guys were that low on plate load with a metallic disc and it didn't smear the lining off the disc? All those discs like that I slipped would make one good run and then buy the 2-3 shift on the second run it would have folded over the lining and taken up all the air gap.

 

[weedburner]

Ram 900 series is puck style sintered iron, I think 8 pucks per side.

 

[yellow rose]

Thanks for the info. It used to be that there were few options for clutches. Now there are tons of options and its hard to decode what and what not to use with limited experience. Thanks for you help.

I hate to come off like a prick (although my wife says I do it very well and she has to live with me so I guess she knows) but I've been doing this crap since 1980 and it frys my *** to see them saying the same crap they were saying back then.

Weed burner is correct. They are more worried about you having a clutch slip than you crunching 3rd gear, killing U joints or twisting axles. You need to be able to control clutch engagement. They say slip, but I don't call it that. You are controlling how fast the disc goes 1:1 with the flywheel and pressure plate. The quicker it goes 1:1 the harder it is on parts.

Think of plate load as the size of a hammer and RPM is how fast you swing it. The higher the plate load, the bigger the hammer. Turn the RPM up and you hit it harder. I could wreck a set of slicks in a few runs. I'd beat the sidewalks out of them. Also, you need to remember that as the surface area of the clutch disc gets less, the specific loading of the disc goes up. Just using imaginary numbers...let's say you have a disc with a full face and it's 50 square inches and you are spreading your 2600 pounds across 50 square inches. Now look at they disc they want you to run. Let's say it only has half of the face area. You now have 25 inches that you are spreading that 2600 pounds over. You double the clamp load.

I know lots of guys run that stuff and swear by it. It's quite likely they are smarter than me and can make it work. It's also just as likely that just by the shear number of failures I've been forced to learn what not to do.

Before you buy anything take some time and make sure you get what you need. I hate to see car beating, parts breaking clutches still being used today. I started in 1980. That's 37 years of watching most of the clutch manufacturers doing the same dumb **** over and over and over again. Drives me absolutely flaming nuts.

 

[684door]

Sams clutch is the puck style metallic on both sides. I can see what you mean about surface area. Never thought of it.
Now the RAM Powergrip HD is a metallic sintered bronze not iron and is a full disc. It os the metallic bronze on both sides of the disc. It says it is set up to slip a bit.
The RAM Powergrip (not HD) uses a combo disc. It is the metallic on the pressure plate side and organic on the flywheel side.
Both the RAMs are 10.9".
I dont want to break something that is for sure, but dont want to beat up the clutch roo much if I run it at the track 20 runs a year also.
These damn things are all 450 bucks and I cant afford to go through a clutch everyother year either. Why is there so many choices? Ha ha ha

 

[weedburner]

Now the RAM Powergrip HD is a metallic sintered bronze not iron and is a full disc. It os the metallic bronze on both sides of the disc. It says it is set up to slip a bit.

Here's a snip of the Powergrip HD description from Ram's catalog, it says sintered iron...

 

[weedburner]

FYI, the regular Powergrip has organic on one side, but the same sintered iron as the Powergrip HD on the other. Both the regular Powergrip and the HD version use the same polysprung hub, and both use the same marcel style carrier as well.

I have a used dual friction regular Powergrip on the shelf, it has a couple years on it and both the iron and organic sides appear to have about the same amount of wear.

 

[yellow rose]

FYI, the regular Powergrip has organic on one side, but the same sintered iron as the Powergrip HD on the other. Both the regular Powergrip and the HD version use the same polysprung hub, and both use the same marcel style carrier as well.

I have a used dual friction regular Powergrip on the shelf, it has a couple years on it and both the iron and organic sides appear to have about the same amount of wear.

I would say if the OP is going to use one of the above clutches that he invest in your screen door clutch thingy. At least he will have some adjustment to tune the hit out of it.

OP...please tell me you have an aluminum flywheel. You don't need a bunch of FW bashing on parts either.

 

[684door]

I have a Ram Billet Steel Flywheel.

I saw that ClutchTamer online. Before even looking for a new clutch, I thought about using or making a product like that.

 

[684door]

Weedburner, I didnt realize till now that you designed the ClutchTamer. Man that is such an ingenious product. It is such a simple design and makes adjustments fairly easy. My father has a 55 Chevy 4 speed ,of course, and both of us thought about purchasing it.

 

[yellow rose]

Weedburner, I didnt realize till now that you designed the ClutchTamer. Man that is such an ingenious product. It is such a simple design and makes adjustments fairly easy. My father has a 55 Chevy 4 speed ,of course, and both of us thought about purchasing it.

Personally, I'd rather have an adjustable clutch. But...if you're not wanting to spend that kind of money, I'd seriously think about his clutch tamer. Damn if I could think of the name of it but you did. You need to have some way to adjust clutch lock up. And his way is relatively inexpensive and simple.

 

[ChargerST]

What would you recommend in my situation (600hp 500" stroker)? I have a B&B/Long pressure plate (2400 base pressure and counterweights) and a McLeod 100 series organic disc (still on the workbench). Should I rather get a 500 series dual friction disc?

 

[yellow rose]

What would you recommend in my situation (600hp 500" stroker)? I have a B&B/Long pressure plate (2400 base pressure and counterweights) and a McLeod 100 series organic disc (still on the workbench). Should I rather get a 500 series dual friction disc?

If you actually have that pressure plate...Id call Cale Aronson at Black Magic Clutches. If your pressure plate isn't adjustable (for base pressure) he may still have the parts to make it adjustable. You won't get a whole bunch of adjustment like you will with a Long pressure plate but you can have some adjustability. I think I can set my base pressure as low as 400 and as high as 990 and then I can add CW which I think is about 8 grams right now.

If you are going to use the rag disc...IMO I think you can drop the base load down to ~1500-1600 and work with your CW to get it locked up at max RPM.

You're only a disc and a tune up away from running a Sof-Lok style clutch. That's what I run in mine.

 

[ChargerST]

Thanks! Just curious how you actually convert a regular clutch to an adjustable clutch? Do you have to change the springs and add adjusters (bolts that preload the springs when turned)?

 

[yellow rose]

Thanks! Just curious how you actually convert a regular clutch to an adjustable clutch? Do you have to change the springs and add adjusters (bolts that preload the springs when turned)?

Yes, you need a different spring, the adjuster and levers with an outboard hole (some levers have an inboard hole as well) and then you can adjust for plate load and counter weight.

The difference between and Borg & Beck cover and a Long cover is that the Long cover is taller. Therefore you can use longer springs and have a much wider adjustment range than you can get with a B&B cover.

For example, and Long cover can go from 300 pounds to about 1800 or even a bit more.
The B&B cover I run is from ~400 to 995 pounds. And I run a Long lever in the B&B cover.