hi guys im about to leave for work so im gona make this as to the point as posible, I just bought a Centerforce Dual friction Clutch for my 95 GSX. what Flywheel would you guys recomend buying to go with the clutch??? Thanks in advance.

Depends on how the car is to be used and how you drive it. The most common aftermarket options are most likely ACT for steel and FIdanza for aluminum. There are others though, like SBR, RPS, Spec, etc. The main criteria is friction surface (aluminum FWs will have a bolt on replaceable friction surface, while ACT will be machined when necessary) and weight. The lighter the weight the better for road racing and autox, but it can get harder to launch. Heavier is better for drag racing (launching). ACT offers two different weights, most others only one.

There are some other issues to consider, like some confusion from multiple types of replacement friction surfaces for fidanzas, ACTs friction welding themselves to the crank or the clutch disc, etc. But to get into that here would be a daunting task... I Would do some research on tooners, nabr, and the like. If you have no need to pass SFI certification (drag racing below 11.99 seconds, road racing, etc), it may be best to just stick with stock ;)

I use the Fidanza flywheel and a centerforce duel friction clutch. Very happy with it. The clutch does not take alot of launching but if you let it cool down after each race its great.

i dont plan on raceing it consistanly everyday.....just when once ina while at the track or when im at a stoplight an some guy in his Mustang wants to get owned. :smile:

In that case I would personally stick with a properly machined stock flywheel. But thats just me! Everyone has his own opinion about this topic...

In that case I would personally stick with a properly machined stock flywheel. But thats just me! Everyone has his own opinion about this topic...

That is what I did. I am not sure if it was worth the money or not to go to something else.

so my stock flywhel will be fine then ?.....and while im at it is their anything else i should look at replaceing while im doing the clutch ?

im trying to build my car starting fro mthe bottom....Clutch...guages...BOV.....brakes suspension......so while im at the bottom is their anything i mite overlook as important to do while at the bottom of the MOD ladder ?

Center diff? Thats probably the number one major driveline failure. Because it typically takes out the rest of the tranny, it pays to fork over the ~500 bucks now, and save the 2000 bucks later. Good list otherwise, but I would add a center diff to it.

what do you mean center diferential ?? how does it get messed up ? how and why ?....and how should i go about protecting it ?

no kidding! a stock properly machined flywheel perfomes better then a lighter aftermarket flywheel when drag racing? i figured the lighter the friction points the less powertrain loss would occure.. i knew it takes stress off the crankshaft increasing revolutions per min, helping things run smoother. But i had no ideah that a stock flywheel would correctivly provide better responce off the line durring drag racing then a light weight wheel. intresing..

sorry i've been drinking.

Yes, center differential. It has two spider gears that take the load whenever the front or rear tires spin more than the other end. Usually its the fronts spinning, since weight transfers to the rear on launch. Check out some of my older videos, you may be able to see the fronts spinning more than the rears. The most common upgrade is a Speed Design (I think Shepperd does his own now?) 4 spider diff. With double the number of spider gears, each one takes half the load. The two gears are small, and when they break the pieces go out into the tranny and destroy it before you can even get the car to a stop. Its about 500 bucks. A tranny rebuild after a broken diff is usually over 2000 because you are replacing at least one shaft and gear set, and odds are you are going to a 4 spider diff for obvious reasons ;)

A lighter flywheel can make launching harder. Remember that the whole purpose of a flywheel is to store energy. Its a battery for mechanical energy really. When you launch the motor wants to stall. The FW will use its stored energy to try to keep the motor running (inertia). With a lighter flwyheel you tend to have to slip the clutch more to get the car moving without dragging the RPMs down too far. So many people have said that this is an issue on the street, but you get used to it quickly and learn to drive around it.

The theory that a lighter FW reduces rotational mass and allows the motor to accelerate faster is correct. But people overestimate the effect ;) When in nuetral, or while shift, all you have is that rotational mass from the motor, flywheel, and input shaft (in the shifting example). So in this case the FW is a sunstantial percentage of this mass. You will notice a differnce, and shifting becomes easier, hence the conclusion that this is a good mod for road race and autox. But consider the drag racing example, or any time you are accelerating in gear. Now you can only rev as quickly as the car can acclerate. So add the weight of the enitre car to the equation this time, and the flywheel becomes a very very small percentage of the total mass ;) In my humble opinion, bearing in mind that I have never perosnally launched with a lightweight flywheel, the .01 seconds you shave off your ET just isnt worth any loss at all in launch capability. LAunching has such a massive effect on ET I refuse to do anything that will hinder my cars performance in that area. ;) But dont take my word for it. Try it, test it, measure it, and come to some conclusion. I dont want one on my car though. The problem comes in where I have to have a SFI certified flywheel. Infortunately they all come in version lighter than stock. Most manufacturers will make one in steel, but its a one off so its not cheap. Still undecided on what I will do about this.

so you think i should just stick with my OEM flywheel?? and you said somehting about having it machined ? what does that mean and what will it do ?

wouldn't machining a flywheel reduce it's weight and thus reducing rotating mass causing the same effect as a lighter flywheel but on a less serious note?

so i should just use the stock flywheel ?? with the Center force dual friction clutch an it will work rea well ?

Machining the FW is done for two reasons. One, for a nice flat surface for the clutches friction material to ride on. The other is to get the proper step hieght, the height between the friction surface and the raised mounting pads. ACT requires a .610 step height. Check whats needed for whatever clutch you use.

I'm saying that I would stick with the stocker, but that doesnt mean its what you should do. Look at all the pros and cons, ask yourself if thats where you need to be spending money at this point in your buildup, etc, and make an educated decision. :)

so will each flywheel need to be machined specifically for each clutch?

Yes. I think most come in .610, since I believe that is also the stock spec. The ACT FWs come stepped correctly for ACT clutches, etc.

so i need to find out what step hight the Centerforce dual friction needs then....does anyone know what kind of shop i would goto to have my clutch machined to the right step hight ? and about how much in usualy costs to do it ?

Its the flywheel that needs to be machined. A matter of terminology perhaps, but its important to use the right terms. Any machine shop will do it. Even the NAPA autoparts stores around here do it. Its 35-40 bucks typically. Just be sure the guy knows that its really important that its cut right. Usually no one pays attention to the step height. If they take 5 thousands off the friction surface, they take 5 off the pads. That leaves whatever wear difference you have accumulated over time. I ask them to measure it for me before I will pay for it. I finally found a guy I trust to do it right, and I have been happy ever since. Nice finish on the surface, and the step height is always balls on.

As far as what is the right height for that clutch, Its probably 610, but ask the manufacturer/vendor what it needs to be. Or try searching tooners, I'm sure this question must have come up dozens of times.

wouldn't machining a flywheel reduce it's weight and thus reducing rotating mass causing the same effect as a lighter flywheel but on a less serious note?

*SHOULD* be a much less serious note.

When you machine the flywheel with a standard clutch install (that is, you're not trying to shave 5 pounds or whatever off your flywheel weight), all you are doing is removing the irregularities in the flywheel so that the clutch plate mates smoothly with your flywheel--just like turning your rotors when adding new brake pads--so you are talking a negligible loss in weight. If you are removing enough metal from your flywheel to effect rotational mass with a standard clutch job, you should probably be REPLACING the flywheel, not machining it :iceslolan

If I can ask a question of my own now, I'm in the middle of a clutch rebuild on my 92 Talon NT. I'm putting in an ACT "Street and Heavy Duty" (that's the 2100, I believe) clutch disk, throwout bearing and pressure plate, so while I'm in the engine, I've replaced vacuum hoses, I'm replacing motor mounts, I've inspected the clutch fork (despite 90K+ miles, it looks ok). The fuel filter was replaced ~6 months ago. Is there anything else I should be inspecting/replacing while the engine is in pieces? I'd be really torqued if I got it all back together again just to discover that the <insert widget here> should have been replaced while I had the tranny out :p

Thanks!

--Mike

the center force is the same as the act i have that clutch

ok.....so far ive got my clutch....my flywheel machining......anything else??....the car has like 84,000 miles on it just incase that helps determine anything. thanks this topics helping alot. keep it up please :iceslolan

...and about how much in usualy costs to do it ?

I just had mine machined today. Here in Anchorage, NAPA wouldn't do it, but they referred me to a shop that would. Grand total was $35, and they did the job in an hour and a half -- I was a happy camper. I probably could have got by without having it machined (it looked to be in pretty good shape), but doing it right the first time is well worth the price, IMO, considering how much effort it is to drop the tranny in the first place.

Absolutely. When the FW is not flat, you usually can't tell by looking at it. Using a FW that is not flat can actually damage the new clutch disc (reduced surface area in contact, more heat). Not worth the risk, well worth the 35 dollars :)

To answer your question, I think you hit all the important stuff. Maybe pull back the boot on the slave and look for fluid, same with the master, check inside the firewall. Any hyrdraulic shortcomings will be made aparent any time you raise pedal pressure. Also check the fork picot ball/stud for wear and clean/lubricate it with some grease, if you havent already.

...Maybe pull back the boot on the slave and look for fluid, same with the master...

'Kay. I'll check those.

...Also check the fork picot ball/stud for wear and clean/lubricate it with some grease, if you havent already.

I haven't done that yet, but I did pick up the grease to do it earlier today. The fork looked to be in good shape--you can see the polished area where it's been making contact, but it doesn't look like there was any appreciable wear.

Thanks for the suggestions!

--Mike