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California Clutch

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#41 distributorguy


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Posted 01 February 2018 - 05:28 AM

Everyone worries about a clutch, but how many people here admit to not having the flywheel ground when you replace it because it "looks good"?  

You can have the flywheel step ground to increase clamping pressure as well - any decent machine shop can do this.  Personally, I made up a rig with a bathroom scale and my shop press to test clutch release pressures and shoot for 310-315 lbs of force (measured on the scale) to release the disc.  You can play with hydraulics to reduce pedal pressure, but this system has always proven effective - even on custom setups like a Mustang clutch on a flathead Ford attached to a T5 with all mechanical linkage.  We use a .015" step ground flywheel with a stock '80 truck clutch in our race truck, although clamping pressure are a moot point when you never get traction.  

#42 scooter



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Posted 04 February 2018 - 10:35 PM

my flywheel is ground with a .005 step, which is pretty insignifigant. im using basically a ka 240sx clutch. 225mm stage 2 ACT pressure plate with a sprung 6 puck. i feel like the pedal is soft but it grips. 

if your in traffic on and off lots it does start to chatter when it gets hot, but it doesnt seem to lose grip. on drag slicks it doesnt seem to slip when i launch it either... 5500 rpm launches is doing some serious 60 foot times on the bottle.  this clutch is rated to 400 ft/lbs and i believe it.  milage wise.. well it Is a metallic clutch so I don't expect it to last super long but it has been in there for a few years now.


if I could find the flywheel to run a 7.25 inch twin disc, it would be in the car.

#43 G-Duax


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Posted 04 February 2018 - 11:43 PM

The RB20 flywheel bolts right up to the KA crank, and there are plenty of OS Giken multi-disk setups floating around on Yahoo-Japan.


Here is one closing in less than 3 hours:


"All of a sudden it started making noise, then started losing power. I limped the car home and tried to get it up the driveway, the engine just died."


Why do people do this?

A $100 tow bill is never as much as the extra damage you cause by trying to "limp the car home".


Don't be that person !

#44 datzenmike



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Posted 05 February 2018 - 06:19 AM

Get a 240mm flywheel from a D21 and a 300zx pressure plate.

Posted Image

#45 Stoffregen Motorsports

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Posted 05 February 2018 - 10:00 AM

I've only ever driven multi disc setups with discs that had no springs, and they were completely undriveable on the street. Or more accurately, they worked well if you basically dumped the clutch. If you let it out normal, the discs would last a month.


I didn't know anybody offered those setups with spring dampened discs. That's probably the difference.