FastAzzEvo

iTrader: (11)

I agree. I am still making phone calls, but the shop that quoted that amount also quoted me 900$ just for labor to replace the clutch. So that is clearly out.

What would you recommend for an Evo owner with lets say 350-450 flywheel torque? The HD or the XT?

elhalisf

iTrader: (171)

some napa part stores have machine shops. i just did a clutch job this weekend, and it cost $29 to get the flywheel resurfaced.

btw, this is a flat flywheel, make sure you tell them that. they probably gave you a quote for a step flywheel.

ACTman

iTrader: (5)

I think our HDSS kit unless you intend on more upgrades later to take you over 500 (honest numbers). If you are at 450 and beat on the car or often run it at the track, then yeah get the XT just for the cheap assurance.

Carlos4g63

iTrader: (1)

Dude I just got a ACT Xtreme Street Disc with a Fidanza Fly Wheels works awesome as hell I got it done at TTP in orlando they installed it for $550. I had they some problem as you and I drove from Jacksonville on a SUnday to get it done worth the money man let me know if you need more info.

TTP Engineering

iTrader: (465)

We would be happy to both hook you up with the ACT line of clutches which we stock 3 Evo versions as well as install it for you for far less $ than you are finding elsewhere.

You will be hard pressed to find an installer that has done more Evo only clutch swaps than us.

uglyevo

iTrader: (8)

I just did my clutch on the cheap and used a resurfaced stock flywheel and the stock pressure plate with an act 6 puck. works great for me

Mr. EvoVIII

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Mr. EvoVIII

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FastAzzEvo

iTrader: (11)

Does anyone know what the clamping force is for the XTSS and the HDSS ?

I read somewhere the stock unit (oem) was around 2000

So the hdss is 2100 and the xtss is 2600?


I read exedy is 3010.


I know this has a direct impact on pedal stiffness as wheel as how much the clutch can hold. The less the number the less ft lbs your clutch can handle correct?

TTP Engineering

iTrader: (465)

They are about 2900 for HDSS and 3250 for XTSS.

I am sure Dirk will follow up also.

The old DSM's used to be about 2100 and 2600.

And NO the pedal stiffness has less to do with holding capacity than the friction coefficient of the disc material and disc type.

FastAzzEvo

iTrader: (11)

thanks for the info, so the pedal stiffness doesn't have nothing to do with the clamping force, or lil to do?

so the the pedal would be stiffer for the xtss than the hdss

ACTman

iTrader: (5)

Stock EVO is about 2200lbs
ACT HD is about 300lbs, XT is about 3400lb
Exedy Stage 1 or 2 is about 2700lb. Exedy advertises their twin at 2205. Not sure about their HD version.

Clamp load is not directly relational to pedal load but it is directly relational to what power the clutch will hold. What you feel on the pedal is the strength of the diaphragm spring and the leverage built into the geometry of the diaphragm. The clamp load is determined by both the diaphragm spring and the leverage points of the pressure plate that the spring is acting upon.

There are a few things we juggle to gain the compromise we are looking for in a clutch. A couple of these are the diaphragm spring load and leverage through the pivot points. When done properly a stronger diaphragm will offer both increased clamp load and increased working range (added clutch life). One tradeoff is stiffer pedal effort. When changing the leverage, we can gain clamp load with no increase in pedal effort. The main tradeoff is a reduced working range (clutch doesn't last as long). By combining the two methods in the right proportions you can get the best of both worlds.

Going back to my opening statement: Clamp load is... directly relational to what power the clutch will hold. There is a simple formula for determining torque capacity of a clutch (it is on our website in the tech section). It is simply multiplying the clamping force in lbs, times the coefficient of friction (approx .25 for organic and .32 for cerametallic), times the number of surfaces (single disc is 2), times the radius of gyration in feet (stock EVO is .328). This will give you a general idea. The problem is getting the correct values for clamp load and friction to start with. You cannot simply take information from one source and compare with another source since the numbers will vary a lot depending on a number of factors.

FastAzzEvo

iTrader: (11)

Ok, so what would be the main differences between the xtss and the hdss other than the xtss holding more tq? Would the xtss last longer or no since it uses the same disc? How much different is pedal pressure of the two?

I'm trying to get the one that will offer me longevity as well as future modifications. I'm only at 300WTQ on a dyno dynamics dyno, but I plan on having close to 400WTQ in the future. If I stay at the 300WTQ for awhile would the xtss take more abuse than the hdss? Or are they the same in that aspect?

ACTman

iTrader: (5)

The main difference is that the XT will hold more torque than the HD because of the additional clamp load. There is a small increase in pedal effort and adjustment required at the pedal. They have about the same life expectancy and will take roughly the same amount of abuse.

FastAzzEvo

iTrader: (11)

decisions decisions!!!