Clutch Masters 89-98 Nissan Skyline 2.5/2.6L RB25DET/RB26DETT 850 Series Street Clutch

A built RB26DETT or RB25DET Skyline that slips the moment the turbos come on needs more clutch than a single disc can give in the space under that bellhousing. Clutch Masters 06045-TD8S-X is the original FX850 twin disc in its Street stage for 1989-1998 Skylines with a push style release, aimed at owners who still drive the car on the road but have outgrown the stock or Stage 2 clutch.

What the FX850 Street twin disc does in an RB Skyline

The FX850 is an 8.5 inch (216 mm) twin disc, sized for gearboxes with smaller bellhousings like the RB cars use. Two discs double the friction area without a bigger diameter. In the Street stage (TD8S) Clutch Masters connects one sprung ceramic disc directly to one rigid Fiber Tuff disc, so the sprung hub damps both discs while the softer second disc keeps engagement friendlier than the all ceramic Race stage. The cover is machined billet aluminum with a Type 3 hard anodize, which Clutch Masters says flexes about .003 inch against as much as .030 inch for a cast cover, so pedal travel goes into releasing the clutch instead of bending the cover. Their QR quick release pressure plate uses three spring loaded bolts to engage evenly and cut internal chatter by up to 50 percent. Expect roughly 50 percent more pedal effort than stock, depending on the car. The background in our twin disc vs single disc guide explains why a twin is easier to live with than a huge single.

Symptoms that say the clutch is the limit

• Tach flares in third, fourth or fifth when boost builds, with no gain in speed
• Hot friction smell after a pull, roll race or a few hard launches
• Stage 2 or puck single disc wearing out quickly on a high boost car
• Judder and chatter as a worn single disc and hot flywheel glaze over

How to confirm before you buy

On a 25 year old import, rule out the hydraulics first. A tired master or slave cylinder, old fluid or a sticking release fork can mimic slip or prevent a full release. Bleed the system and check for oil leaking from the rear main seal, because oil on the friction surface will ruin any clutch. Our clutch slipping guide shows how to tell real slip from other problems, and our manual transmission repair cost guide helps you budget the whole job.

Fitment

Clutch Masters lists 06045-TD8S-X for the 1989-1998 Skyline 2.5L RB25DET and 2.6L RB26DETT with a push style release, plus the 1989-1993 2.0L RB20DET. Release style is the critical check: if your RB26DETT car still runs a pull type clutch, this kit is not the right one, so confirm what is in your car or send us the chassis code and any conversion history. The -X version is sold without a flywheel. Clutch Masters offers this Street stage with aluminum and steel flywheels under different suffixes, and a twin disc needs a flywheel made for it, so confirm the flywheel you will run before install. If you would rather have a complete kit with flywheel, the FX850 PRO twin disc with steel flywheel and the FX725 PRO twin disc cover the same cars. More options are in our clutch and rebuild kit collection.

Install notes

• Replace the pilot bearing whenever the gearbox is out; a pilot bearing puller gets the old one out without damaging the crank.
• Stack the discs and floater exactly as the instructions show, center them on the alignment tool and torque the cover in a crisscross pattern.
• Flush the clutch hydraulics with fresh brake fluid and bleed thoroughly; a vacuum bleeding kit helps on cars with a remote slave. See how to bleed a hydraulic clutch.
• Some rattle at idle with the pedal out is normal for a twin disc. Break it in gently before boost; see clutch break-in.

Does 06045-TD8S-X include a flywheel?

No. The -X version is the clutch assembly without a flywheel. Clutch Masters sells versions of the same Street stage with aluminum or steel flywheels, and a twin disc needs a flywheel made for it, so confirm your flywheel before install.

Will this fit an R32 or R33 GT-R with a pull type clutch?

Clutch Masters lists this kit for push style RB25DET and RB26DETT applications. If your car still has a pull type release, it needs a different kit. Send us your chassis code and details and we will help you match it.

What is the difference between Street and Race stages?

The Street stage pairs a sprung ceramic disc with a rigid Fiber Tuff disc for smoother engagement. The Race stage uses ceramic on both discs for more bite and less street manners.

Is a twin disc noisy?

Twin discs can rattle at idle with the pedal released. Clutch Masters uses its QR pressure plate design to reduce internal noise and chatter, but some sound is normal.

What else should I replace with it?

Replace the pilot bearing and release bearing, inspect the release fork and pivot, and flush the clutch hydraulics with fresh brake fluid.

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