aluminum flywheel 89sc

Douglas Walker

Registered User
I am looking for information on our options for aftermarket flywheels. I have looked alittle at Mcleod and Spec. Im looking to go towards the aluminum style. For people that have taken this route what are your thoughts and suggestions.

Doug
 
SPEC Stage III

Douglas Walker said:
I am looking for information on our options for aftermarket flywheels. I have looked alittle at Mcleod and Spec. Im looking to go towards the aluminum style. For people that have taken this route what are your thoughts and suggestions.

Doug
I have an '89 XR-7. I went with the alum. SPEC flywheel. One of the things I like about it is that it has a replaceable friction surface. Instead of cutting the flywheel, you simply replace the steel friction plate. I have no idea of the cost difference between replacing the SPEC plate vs. resurfacing a cast or steel flywheel. Also you won't have the trouble of shimming the slave cyclinder when the flywheel is cut.

Several years ago, some Gear Head Rag did a dyno test between OEM cast flywheel & alum flywheel. It showed conclusively that the alum. flywheel made (actually Released) more hp than the heavy cast flywheel. The ONLY place where the cast flywheel was superior, was DURING the shift. The heavy flywheel was able to store more kinetic energy & release it back into the drivetrain when the clutch was let out. Also, because the alum. flywheel is lighter, it rev'ed a couple of hundred rpm higher During the shift, than the heavy flywheel did. That's merely a factor of weight.

On SPEC clutches! I have the Stage III, which I LOVE!!!!! One thing though, the SPEC clutch is VERY HEAVY!!!!!!!!!!! I wish now that I had got the lightened clutch. I think that the weight I saved with the alum. flywheel, was offset by the heavier pressure plate.

Here are the weights I measured from my UN-lightened SPEC Stage III & alum flywheel:

Pressure Plate: 389.9 oz. = 24 lb. / 5.9 oz.

Aluminum Flywheel: 187.6 oz. = 11 lb. / 11.6 oz.

Stage III Clutch Disk: 64.4 oz. = 4 lb. / 4.4 oz.

Throw Out Bearing: 6.8 oz.

Pilot Bearing: 1.8 oz.

68COUGAR
 
the spec stage2 to a CFDF in weight was less then 2-3LB so that not to much at all. when I was ordering my clutch I talked to spec and they said for a car such at the SC that puts down a lot of TQ your better off with out doing that.
 
Doing What?

Jason Wild said:
the spec stage2 to a CFDF in weight was less then 2-3LB so that not to much at all. when I was ordering my clutch I talked to spec and they said for a car such at the SC that puts down a lot of TQ your better off with out doing that.
Doing what? SPEC 2? CFDF? Lightened? UNlightened?

Connfused 68COUGAR
 
I've got the 13.5lb McLeod flywheel too. I looked at Specs and it looks the same. I dunno of mcleod makes these or Fidenza or who.....but I'm betting one company sells for everyone.

Just make sure you get one with the dual bolt patterns for both early and late style clutch. It gives you more flexibility.

With the 13lb flywheel, the car revs freer. YOu'll notice the gas is touchier....and you have to adapt when you take off. A blimp of the gas will get the revs up to 1500 rpm right away. The car pulls a little better in all the gears too. I dynoed an old combo at 263 HP and then added a 10% ESM jackshaft (with my 5% SVO pulley) and the aluminum flywheel. I then dynoed 270 HP. So the flywheel must be working. Jumping from 5% to 15% OD shouldn't really have picked up much if any HP.

Micah
 
The McLeod is an exact image of the stock flywheel (all aluminum flywheels have a steel friction surface) whereas the Spec is slightly lighter. Big deal.

I don't think either will have an advantage over the other.

I do know that several people have complained about the abruptness of engagement with the Spec. I find the DF to be much more progressive. Either one should be able to withstand whatever you toss at them.
 
Me and one of my buddies was talking about this tonight. I asked him about the Alum. flywheels and he said that he bought one and it sucked. The way he explained it to me was : Where the gear is for the starter will want to go in torwards the center, there for taking friction surface away from the clutch and making it less freindly. Hes in to the VW bugs and all that stuff, which in mean, hell, he made a few bugs in his day (hes 65) that would smoke quite a few cars in this day and time, granted they dont weigh a whole lot, but if any of you have ever seen a VW bug motor tore down and actually PICKED up the BLOCK!!!!! then they can be a powerfull little motor. He told me that taking it to a machine shop and see if they can lighten it any, well i guess if thats possible.

Derek
 
SPEC vs. OEM

XR7 Dave said:
Spec is slightly lighter. Big deal.

I do know that several people have complained about the abruptness of engagement with the Spec. I find the DF to be much more progressive. Either one should be able to withstand whatever you toss at them.
About the abruptness of the SPEC! Hey! If you Want an OEM, 'not sure if I'm stepping on the clutch or not', then Don't by a SPEC.

But....................If you want to feel when the clutch engages & disengages, & if you value Drive-able Performance, before OEM (I don't know if I've shifted, or not), Get the Spec.

It all comes down to how much clutch disk slip you want!

The SPEC III disk that I have, is a puck design. It's Perfeftly driveable, BUT, you can not let your grandma let the clutch out. Any Guy who Rows his Boat, can live with a SPEC III. But if you what to whine about clutch pressure, Buy a RICER!!!!!!!!!!!!!!!!!!!

68COUGAR
 
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i have a an el cheapo clutch and i can sure ~~~ hell feel when it engages... it will kick you back into the seat with the front wheels almost coming off the ground... didnt understand the last part about a RICER?
 
68COUGAR said:
About the abruptness of the SPEC! Hey! If you Want an OEM, 'not sure if I'm stepping on the clutch or not', then Don't by SPEC.

But....................If you want to feel when the clutch engages & disengages, & if you value Drive-able Performance, before OEM (I don't know if I've shifted, or not), Get the Spec.

It all comes down to how much clutcht disk slip you want!

The SPEC III disk that I have, is a puck design. It's Perfeftly driveable, BUT, you can not let your grandma let the clutch out. Any Guy who Rows his Boat, can live with a SPEC III. But if you what to whine about clutch pressure, By a RICER!!!!!!!!!!!!!!!!!!!

68COUGAR

Relax man, the point is that there is a difference in how they engage. Several very high HP people including myself have put the CF DF to some serious abuse and can testify that it is plenty strong.

As for the "abruptness" of engagement of the SPEC, if you like to break parts by all means get the most abrupt clutch you can find. However, if you aren't into changing tranny tailshafts you might want to consider that an easier engaging clutch might have a benefit.
 
I am into the shelby dodge cars, and for us

the aluminum flywheels are popular and worth it because they are alot lighter and provide a little better performance shifting and all that

but for the guys that make there cars purely for the track, they stick with the stock flywheels because they are heavier and made of a harder metal, which most OEM flywheels are regardless or make and model

so i would suggest sticking with a stock style flywheel if you are doing ALOT of hammering on the clutch from a stand still and the aluminum flywheel for every other type of driving
 
Gerber....I figured most guys who took their turbo dodges to the track didn't buy the aluminum flywheels because of the cost. Most of those guys seem to focus on the mean and potatoes of going fast.

For the Centerforce guys.....do any of you keep the pressure plate weights attached or do you remove those when installing. Some people say you should ditch em and others say to keep em.

Micah
 
Everyone keep in mind that aluminum flywheels have STEEL ring gears for the starter and STEEL friction surfaces for the clutch.

They are a multi-piece design allowing aluminum to be used for the main mass of the assembly.

If you're planning on a performance oriented car, putting a steel flywheel back in a Thunderbird SC is a waste.

If you're a member you can see more feedback on the aluminum flywheels here:
http://www.sccoa.com/forums/showthread.php?t=32137&highlight=aluminum+flywheel+weight
 
With all that is said. Im gonna stick with my CF DF clutch and go with the spec aluminum flywheel.

My next questions since I had my motor balanced am I gonna need to balance the new flywheel to match the old or will it matter.

As for the reply from Micahdogg is there any other info out there on this?

For the Centerforce guys.....do any of you keep the pressure plate weights attached or do you remove those when installing. Some people say you should ditch em and others say to keep em
 
I've got a Fidanza Aluminum flywheel. It's drilled for the 11" and 10.5" clutch. I had to use the F150 starter with it. I've been running that flywheel with the stock LUK clutch and I've got no issues with it. I like how the engine revs noticably quicker. It takes some getting used to taking off slow from a stop. I stalled it out all the time when I first got it. It either wants to launch or stall, not take off slowly.
 
Flywheel and pressure plate should all be zero balanced if for our cars.

I'd check with the shop doing the balancing to see what all they can work with. Ideally the harmonic balancer is with the crankshaft when everything is being balanced. I haven't heard or flywheels also being attached, but it wouldn't hurt if they can support it.
 
Dan, do you mean 11 and 11.5 inch clutch?

Again, on the CF pressure plate weights.....they have this goofy string of weights that wraps around the "fingers" in the middle of the pressure plate. They claim it's a crucial part of the set up, but others say after 2000 rpm they are pointless for any kind of balancing so go ahead and rip em off.

I would probably remove them as they just look retarded....seems more like a gimmick than anything else. Oh, and I'm almost positive CF used "Luk" pressure plates, but just painted them orange. I think they are even stamped "Luk." So if luk doesn't use the weights that's even more reason to ditch em IMO.

Micah
 
Micah, from what I understand, the weights on the CF pressure plates are there to assist the clamping force of the diaphragm fingers at higher RPM. The idea is that they can have relatively light pedal effort, but still have enough clamping force with the weights adding some centrifucal force. I have no tech on how well that actually works.

And I'll agree with Dave, the SPEC clutch is very grabby, and quick to take up. Mine is attached to a McLeod aluminium flywheel, it's the early 11" size clutch. When I was chatting with several people with the same clutch at the Shootout, they concurred. Makes it tough to launch the car, it seems to be either on or off. Hopefully with more practice I can get better with it.

cheers
Ed N.
 
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