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-   -   Purchase a new clutch for my fd???? (https://www.rx7club.com/rotary-drag-racing-167/purchase-new-clutch-my-fd-1045628/)

Samito Built 09-07-13 01:39 PM

Purchase a new clutch for my fd????
 
2 Attachment(s)
Well I just bought a Act pressure plate with a solid full ceramic disk clutch and have never seen this clutch before. Thought Id ask you guys first since it was used for drag racing? This clutch is pretty beefy and heavy as well. The part numbers is very hard to read so I'm stumped. Regardless its in great shape and I plan to use it for my FD since I'm into bracket racing need something that can hold up to the task. Any input will be appreciated.:)

C. Ludwig 09-07-13 02:07 PM

May actually be a RAM disk. Do you see the numbers 5135 on it? If so, it's a RAM. This thread outlines the differences pretty well. https://www.rx7club.com/rotary-drag-...sk-fd-1008973/

We just got a new RAM. They don't list a 9.5" disk on their site, but they put one together for us with a Chevy 26-spline. No additional cost for the non-off-the-shelf part. It was $190 to our door.

ArmyOfOne 09-07-13 02:32 PM

Sammy, how thick is it?

Samito Built 09-07-13 03:26 PM

7.47 mm thickness on the pads. I verify the #5135 and its on the disk so I'm assuming its a Ram. So do I need shims in order for this to work?

Samito Built 09-07-13 03:46 PM

Well doing some research looks like this is a overkill for my car. Since I'm using a stock synchro tranny it sounds like these clutches don't help with fast shifting. They also need to be shimmed since the pad is thicker might just sell the clutch and down grade not sure.

Bacon 09-07-13 04:10 PM

Yep that looks like a ram (I've had 2)
On brand new press plate yea you will need to shim, to much thickness = too much preload and takes clutch out of sweet spot for peak pressure, mc master car sells shins, think .065 was correct thickness to shim off the bat.
I just went all new this year with clutch and to get the diaphr to sit correct it needed .080
But the beauty is now that it all worn in, I can start stepping down shims and have full clutch life to wear down (compared to act/stock thickness)
Easy to change through clutch window

But if your using a used pp/ not resurfed fw chances are you don't need to shim, last year my end of season disk replacement didn't need any shims

Will shift fine on syncros, it's not the clutch but the syncro's that limit you

Samito Built 09-07-13 04:31 PM


Originally Posted by Bacon (Post 11567701)
Yep that looks like a ram (I've had 2)
On brand new press plate yea you will need to shim, to much thickness = too much preload and takes clutch out of sweet spot for peak pressure, mc master car sells shins, think .065 was correct thickness to shim off the bat.
I just went all new this year with clutch and to get the diaphr to sit correct it needed .080
But the beauty is now that it all worn in, I can start stepping down shims and have full clutch life to wear down (compared to act/stock thickness)
Easy to change through clutch window

But if your using a used pp/ not resurfed fw chances are you don't need to shim, last year my end of season disk replacement didn't need any shims

Will shift fine on syncros, it's not the clutch but the syncro's that limit you

Oh I see! The clutch and pressure plate I have are used but in good shape.:scratch:

Bacon 09-08-13 11:05 AM

ok, so when you see .062- .065 your gonna be like really, that makes a difference
heres my clutch setup 201, its all about the fins of the diaphram, they should be perpendicularly flat, not in not out
if you install all new stuff the fins will be pushed out, (throw out retainer) , if its right it the fins will sit flat
tough to describe typing, but if the disk is thicker than the sweet spot of the clutch (.315 new to .270 replace) so the sweet spot is .045 of a inch, so now that .062 shim can make the world of difference
so it depends how worn flywheel is, and how worn pressure plate is,but once you install it without shims, the fins will tell you if you need shims, theoretically once you have the math really the disk thickness can give you your base line for shim setup.
all i shim is the bolts, not the pins, this way you don't have to fully remove clutch to change shims down the road. like you can loosen all 6 bolts through inspection window, then remove one bolt at a time and change shims.
but initall setup not as hard as it sounds, just buy a few thicknesses so you can make a few thicknesses

Samito Built 09-08-13 12:40 PM


Originally Posted by Bacon (Post 11568204)
ok, so when you see .062- .065 your gonna be like really, that makes a difference
heres my clutch setup 201, its all about the fins of the diaphram, they should be perpendicularly flat, not in not out
if you install all new stuff the fins will be pushed out, (throw out retainer) , if its right it the fins will sit flat
tough to describe typing, but if the disk is thicker than the sweet spot of the clutch (.315 new to .270 replace) so the sweet spot is .045 of a inch, so now that .062 shim can make the world of difference
so it depends how worn flywheel is, and how worn pressure plate is,but once you install it without shims, the fins will tell you if you need shims, theoretically once you have the math really the disk thickness can give you your base line for shim setup.
all i shim is the bolts, not the pins, this way you don't have to fully remove clutch to change shims down the road. like you can loosen all 6 bolts through inspection window, then remove one bolt at a time and change shims.
but initall setup not as hard as it sounds, just buy a few thicknesses so you can make a few thicknesses

Appreciate it bacon thanks for the descriptive detail it really helps.:icon_tup:

Bacon 09-08-13 10:48 PM

1 Attachment(s)
11/32 ID

13/16 OD

Save you some time with McMaster

ArmyOfOne 09-09-13 11:33 AM

Thanks for the info on this Bacon. Much appreciated!


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