ACT Technical Center / FAQ | Technical ~ ACT / Performance Clutch Kits, Clutches and Flywheels

At ACT our best customers are people that know what they are buying and why. Every clutch design has benefits and tradeoffs so explore all the resources available to make the best choice for you.

Most performance enthusiasts relate more to horsepower rather than torque, but clutch capacity is best measured in terms of torque. Think in terms of comparing a high rpm 250hp Honda Civic versus a Dodge Cummins turbo diesel which has the same horsepower. The diesel will need about three times the clutch capacity because the engine produces about three times the torque. We started rating our clutches years ago so people will have an honest estimate of what to expect. We provide the percentage of clamp load increase and the estimated torque capacity right on our application chart.

ACT Outperforms
Take a look at the graph and you will see that our pressure plates will provide a higher clamp load for a longer distance than our typical competitor. This exclusive ACT design translates into longer clutch life, a more positive feel and better shifting. There will be an increase in pedal effort ranging from slight to heavy depending on application.

	Quality Through and Through ACT clutches and flywheels offer proven performance for both street and full race applications. ACT employs vehicle testing, dynamometer results, laboratory testing, and the latest in CAD, 3D modeling, and FEA (Finite Element Analysis) software to develop many of their products long before they come to market. There is no guesswork and very few surprises.
	Power to the Pavement Calculated results are given for each clutch by publishing the increase in clamp load and estimated torque capacity in our catalog and on our website. These are not mere marketing claims, but accurate estimates based from solid engineering principles, confirming what we already know from the track. Each pressure plate is load tested and cycled to ensure parts meet ACT's strict quality standards.
	Added Value Extra steps are taken with virtually every ACT part to provide added value. Some of these steps include improved designs, hardening on critical wear points, computer balancing and SFI certification. ACT products not only out perform the competition, but out last them as well. Rather than take shortcuts to cut cost, we insist on quality. ACT adds value that you may not initially notice, but you will appreciate thousands of miles later.
	ACT Designs ACT designs and manufactures their parts using unique engineering ideas that include proprietary trade secrets. This is especially true when it comes to diaphragm spring technology and what separates ACT from other brands. As a result, ACT clutches are unequaled for their consistent feel, high torque capacity, good durability and long wear life.

If you have any questions or need assistance, please contact ACT’s customer service department. WE WILL BE GLAD TO SERVE YOU. (661) 940-7555

	How much does an ACT clutch weigh?
	The weight of the ACT clutch assembly will usually be the same as a stock O.E.M. clutch assembly.

	My ACT clutch looks different than the previous clutch. Do I have the right parts?
	There are many manufacturers and designs for clutches. We do our best to use the best parts for your application. Check the part numbers and compare what is listed on our application chart for your vehicle. If the components fit properly without modification, chances are you have the right parts. If it appears something needs to be modified to make it work, stop and contact our tech department.

	Is it necessary to use the alignment dowel pins on my clutch?
	Yes! The alignment dowel pins properly locate the pressure plate to the flywheel. Without these pins severe vibration and engine damage can result. The alignment dowel pins should always be replaced if they are damaged, broken off, or missing from the flywheel.

What clutch bolts and torque specifications should I use?

When using stock clutch bolts, refer to the manufacturer's service manual for proper torque specifications. New bolts are highly recommended. ACT suggests using SAE Grade 8 or Metric Grade 10.9 fasteners and increasing the torque specifications (5/16 or 8mm bolts can be tightened to at least 30 ft. lbs. of torque). Lock washers or thread locking compound is also recommended. Proper torque is crucial to your safety, take the time to get the correct pressure plate assembly and flywheel bolt torque specifications and tighten the bolts correctly using a high quality torque wrench. Also be sure to tighten bolts using a diametrical pattern as indicated in your vehicle's repair manual. Never use air tools for installing or removing clutch bolts!

	Are there any special modifications necessary to install an ACT clutch?
	All ACT clutch assemblies are designed to be a direct bolt in replacement for the stock clutch assembly. Pedal height adjustments are sometimes necessary depending on application. Please refer to our technical bulletins for further information.

	Are ACT clutches balanced?
	Yes! All ACT clutch assemblies are computer balanced to help ensure smooth operation.

	Is changing the pilot bearing recommended when installing a new clutch?
	Yes, if your vehicle is equipped with a pilot bearing or bushing, it is recommended to replace and properly lube the pilot bearing/bushing when changing the clutch.

	Do ACT clutches require a break in period?
	For organic street discs "00 and SS" we recommend breaking in the clutch for 200-300 miles with mild engagement such as stop and go city driving prior to racing or spirited driving. ACT race discs usually only require a few hard slips to lap in the surfaces prior to normal driving or racing. Do not overheat the clutch during the break in period.

	Can an ACT disc be purchased separately?
	ACT discs can be purchased separately, however because of the labor involved in changing a clutch we do recommend replacing the entire clutch at the same time.

	Does ACT make anything for automatic transmissions?
	ACT only offers components for manual transmissions. The automatics use a totally different setup all together and nothing is interchangeable.

	My new throwout bearing appears to be off center on the bearing retainer and wobbles. Is it defective?
	There is nothing wrong with the bearing. Vehicles that have a self-centering bearing may appear to be off center or improperly manufactured, however, rest assured, the bearing will align and center itself properly during normal usage.

Can an ACT Race Puck style disc be used for daily driving, and is it recommended?

The race disc is a very aggressive disc that offers a no nonsense performance action. The engagement is so harsh that taking off from a stop can cause chatter and or an uncomfortable noise. The chatter and noise has no affect on the performance on the clutch and no affect on the drive line components. This type of disc should only be used in a professional race setting, and never used on the street. ACT always recommends using an organic disc on the street because it offers a smoother engagement and a longer lasting performance value for everyday drivers.

What is a flywheel step?

The flywheel step is extremely crucial for the clutch to work properly. The flywheel step determines the proper working range of the pressure plate. The step is the distance between the friction surface, and the pressure plate mounting point on the flywheel. Depending on the make and model of the car it can either be an UP step or Down step, and sometimes the flywheel will be flat. Check the manufacturers specifications about the proper flywheel step for your application.

	Are ACT clutches repairable or rebuildable?
	Rebuild or repair may be possible in some cases, after inspection of the clutch assembly. Please contact our technical department for further information. Because of special modifications we do not recommend servicing by a general clutch rebuilder.

	How do I purchase an ACT product?
	ACT has many distributors around the globe feel free to contact an ACT customer service rep for the nearest one to you. ACT products can also be ordered online at www.advancedclutch.com/store

	What parts in the clutch system linkage should I inspect before installing a new clutch?
	If you are having clutch trouble prior to installing an ACT clutch, find the cause of the problem before installing the new clutch. There are many problems caused by worn or faulty linkage, oil contamination, and misalignment or transmission damage. Please see ACT's installation instructions and your vehicle's repair manual.

	Can the XACT Flywheels be resurfaced, and is there a special process?
	Yes, ACT XACT flywheels can be resurfaced just like a stock flywheel and there is no special process. Make sure that the proper flywheel step is done, as this will affect the clutch function if it is not correct.

	What could cause poor shifting quality?
	Improper clutch release caused by faulty linkage and/or improper adjustment.

	What could cause clutch slippage?
	Improper clutch adjustment, lack of freeplay.

What would cause inadequate clutch release?

Inadequate clutch release can be caused by many problems. Possible causes may be as follows: Clutch linkage not properly adjusted or reset. Flywheel not resurfaced before new clutch installed. Flywheel surfaced improperly (I.E. Incorrect flywheel step). Flywheel machined too thin or not manufactured to stock (O.E.M.) specifications. Lack of lubrication on linkage or release bearing collar. Linkage worn or damaged. Hydraulics defective, leaking or air in the system. Cable stretched or damaged. Pilot bushing binding due to improper bellhousing alignment, bellhousing damaged, or loose. Clutch disc installed improperly. Clutch disc hub rubbing against flywheel bolts. Clutch disc binding on input shaft, damaged splines. Input shaft bent causing clutch disc runout. Pressure plate assembly and/or clutch disc bent or damaged. Clutch disc is too thick or has excessive Marcel (Too much cushion between the friction facings). Pressure plate has defective or damaged torque drive straps. Damaged, worn, or improperly installed pilot bushing/bearing. Oil or grease contamination on clutch facings. Damaged or worn throwout bearing collar. If you have any further questions, please call (661) 940-7555 and ask for the tech department.

What could cause clutch chatter?

Chatter is when the car shudders as the clutch is being engaged. Possible cause may be as follows: Flywheel has excessive run-out. Flywheel was not resurfaced or improperly resurfaced before the new clutch was installed. Damaged or excessively worn CV joints. Bad U-Joints in drive shaft or U-Joints misaligned. Excessive backlash in differential. Excessive driveline angle. Bad leaf springs, bushings or mounts. The use of an aggressive clutch disc designed for racing. Defective pressure plate and/or disc. Disc has inadequate Marcel (Not enough cushion between the friction facing.). Oil or grease contamination on clutch facings. Worn or damaged clutch linkage. Bent pressure plate assembly and/or disc. Improperly tuned engine. Worn or damaged engine mounts or transmission mounts. If you have any further questions, Please call (661) 940-7555 and ask for the tech department.

	I just ordered an ACT product. How do I check to see if the part is right for me?
	ACT customer service can answer many questions concerning fitment and custom applications feel free to contact us at 661-940-7555

Is flywheel resurfacing necessary before installing a new clutch?

A smooth, flat flywheel surface is essential for proper clutch operation. Flywheels are subject to heat, scoring and warping during use. If upon careful inspection there are signs of scoring, heat damage or warpage the flywheel should be resurfaced or replaced to assure good clutch performance. Resurfacing should be done on a flywheel-grinding machine only. Refer to your factory service manual or ACT information for resurfacing specifications (Flat, Step, Etc.). WARNING: IF YOUR FLYWHEEL SHOWS ANY SIGNS OF CRACKING, REPLACE IT! Never roughen the flywheel clutch surface with sanding as this reduces clutch life. The surfaces are designed to rub against each other (Producing Friction), not tear into each other (causing abrasion). If you have any further questions, please call (661) 940-7555 and ask for the tech department.

	Can I use an aftermarket flywheel with an ACT clutch?
	The ACT clutch system is designed to work with both stock and good quality aftermarket flywheels. Inferior aftermarket flywheels may have trouble with warpage or high wear. If you are replacing your flywheel, be sure that the new flywheel meets the same specifications, such as proper step, ring gear tooth count, flywheel thickness, ring gear offset, Etc.

	Will an ACT clutch increase pedal effort?
	ACT pressure plates are specifically designed to handle high torque applications. With ACT's durable design you can expect to have an increase in pedal effort between 15-80% depending on application. We could design our clutches with less pedal effort but longevity, torque capacity, or engagement quality would suffer.

	How long can I expect my new ACT clutch to last?
	All ACT products are designed with longevity in mind; however, clutch life will greatly depend on the vehicle, your type of driving and output of the engine. For example a vehicle driver in heavy stop and go traffic will have a shorter clutch life than the same vehicle that is driver on the open highway.

	Which ACT clutch assembly is best for my vehicle?
	It is important to match the proper ACT clutch system with the vehicle and its intended use! Knowing what characteristics you want in a clutch and the power capability of the engine is important.

	What components are in an ACT clutch kit?
	All ACT kits contain a pressure plate and clutch disc, release bearing and alignment tool. Pilot bearings are in selected kits that call for a pilot bearing and have it available. Kit component parts are listed on our application chart.