Race Clutch Options - Circuit Racing
 

Hey guys,

Did some searching and rolled a donut on this.

I'm rebuilding at the end of the season and looking to replace my clutch when the engine and trans come out. I'm after opinions and options on alternatives that won't cost a bomb (like less than $500).

Here are my needs:

• Car is atmo and has 170-190whp (hopefully closer to 190whp post rebuild)
• Using a Fidanza 1.8L flywheel
• Clutch needs to modulate as we do standing starts in my class and it is critical to get off the line well in a sprint race
• I'm running Hoosier R80 rubber and an OS Giken diff which will work it hard on starts
• Needs to be durable and survive repeated and regular trips to 8200rpm in a car with solid engine mounts and shitloads of NVH

With this in mind, I'm thinking of steering clear of a 4 or 6 puck as they aren't easy to get off the line consistently. I'm also concerned about springs in my clutch disk as I know they can fatigue and crack over time, especially in high NVH cars like mine.

I can't really afford a twin plate, and besides, I have driven a Giken and a Tilton twin plate in a Miata and they were both like an on/off switch with zero modulation.

I have been leaning toward a garden variety ACT HD organic, even though it is sprung in the disk. My power levels aren't that high, and I had one in my turbo roadie and it was awesome. Just not sure how it will cop racing conditions over a few seasons of pounding.

Thoughts? Options? What are the autocrossers using? I know you guys beat on your clutches.

I have the ACT that Trackspeed sells. I've had no issues with it, but IIRC Andrew was running one in his PTE car and he likes it as well. The pressure plate is rated to around 300 ft-lbs, and while stiffer than stock, it's still really easy to modulate.

I'm using the ACT XTSS and it modulates well and holds a lot of torque because it is a street style disc and a really strong pressure plate.

AT 170-200hp you dont need more than a FM1 or ACT HD (NOT XT)

If Emelio has any in stock I would recommend the 949 sport clucth. You might even be able to get away with the 1.6 version since you are NA.

I've won many a pro-solo with standing drag tree starts using a 7 lb 1.6l fadanza XT with an unsprung 4 puck. drive it on the street no problem as well. ZM1-XTR4 rated at 350 ft-lbs.

significant advantage using lighter smaller diameter 1.6L stuff. at your torque you might could get away with the SS disk. 195 ft-lbs whith HD pressure plate 270 ft-lbs with XT pressure plate in the 1.6l size.

With the SPM Sport clutch out of stock, my go-to clutch is the ACT HD. I put the 1.6 version in Thumper (my SPM) this year and it has been perfect. As streetable as a stock clutch, but holds 125wtq for a season without any trouble (a stock clutch would last 15-20 hours before letting go).

Awesome - ACT HD it is. Thanks guys.