[lust4speed]

Moot point on the external balance since you mention that the engine will be zero balanced - which is good, but that means that the flywheel also needs to be zero balanced. So forget about any flywheel advertised with external balance.

All Pontiac V8's from the factory were external balanced with a six inch-ounce variance in the flywheel or flexplate. A stock engine can use any flywheel meeting the Pontiac spec as externally balanced. Once you have the machine shop neutral balance the engine then the external flywheel option is off the shelf and the neutral balance flywheel must be used. While I have machine shops change the balance of flywheels, at the current labor cost it is usually better to go with a new flywheel. By the time the flywheel is resurfaced and neutral balanced you are adding up costs pretty quickly.

[scott70]

Thanks for the update. I’m also trying to understand the whole thing. I’ve always run my gto with the original m21 trans and flywheel and centerforce clutch but last summer installed a tkx..new billet McLeod FW,, PP and disc. The engine had been rebuilt and balanced with the oem FW. The spun balanced the oem flywheel and tried to match the balance of the new billet to the oem which the added a screw on small aluminum weight. Now the car had a small but noticeable vibration. I removed the weight and it seemed better. As soon as I can drive it again I will add the screws that held the weight on and see how that feels. Not very scientific if you ask me. I wish I had added a new neutral balanced FW back in the day and had them neutral balance the motor

[HWYSTR455]

Yeah, not sure i understand this whole thread either, but as a generic comment, it is best to have a zero internally balanced engine and use zero balanced flywheel and balancer.

Which brings the question of, is your balancer an OE type or aftermarket?

I went through something like this early on with my 'bird, and I went the painful expensive route to fix it. Wish I would have done that from the start, just to add.

I saw a comment about the register too, and know that '76-up has a smaller register. That's important to know when purchasing new.

No way shape or form would I EVER go back to a cast FW, I've been in 2 cars when they came apart. Just do it, go steel.

Several companies make 11" PP & disc setups that fit on a 10.5 (10.4) bolt pattern, another just to say, McLeod I know is one of them.

On balance, always have the FW and PP balanced, even if they claim/advertise as zero. Many are not as the advertise, and it's always possible somewhere along the way it got switched in a box.

Machine shop I used to use would use a punch and put 3 dots on a leg of the PP and on the face of the FW for easy indexing. If the shop you use does a sharpie mark, back it up with the punch method. You will be glad at some point that you did.


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[grivera]

My 64 had an internally balanced engine and the prior owner bought a TKO600 from MDL with neutral balanced FW and pressure plate. I noticed there was a slight vibration and after several attempts to fix it, I checked the FW and noticed it had a series of holes in it. It turned out MDL sent a FW for an "externally balanced" engine . I sent it back to them and they zero-balanced it.

[scott70]

So it sounds like if you are building an engine today you should really have it neutral balanced. With a neutral, balanced, flywheel, pressure plate, balancer, etc. that way if you ever have to replace any of these parts, they were already neutral balanced, and should be a direct bolt on. Except for the case of a supposed neutral balanced item and it actually isn’t like my MacLeod pressure plate that was supposed to be neutral balanced, but when they checked it, it wasn’t. When I bolted it on, it had to be indexed to a certain position. But it doesn’t sound like there’s a great way of adding a neutral balanced item to a motor that wasn’t neutral balance to begin with

[Formulas]

Zero / Internal balance at this point in time just makes life easier now that you cant run to a Pontiac dealer and get a useable flywheel

[HWYSTR455]

Originally Posted by scott70

.. When I bolted it on, it had to be indexed to a certain position.

Yes, make punch marks on PP and FW for future reference.

Did they just use a sharpie to mark it?

Clutch setups being friction material and true surface should be treated just like a brake job, no oily finger prints and spray down with brake cleaner before final assembly. If the index marks are made with a sharpie, guess what?

(EDIT): Diaphragm PPs are basically once-and-done, BB, Long, and multi-disc clutches you can reuse/rebuild the PPs, and marking the index is more critical.
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[scott70]

Originally Posted by HWYSTR455

Yes, make punch marks on PP and FW for future reference.

Did they just use a sharpie to mark it?

Clutch setups being friction material and true surface should be treated just like a brake job, no oily finger prints and spray down with brake cleaner before final assembly. If the index marks are made with a sharpie, guess what?

(EDIT): Diaphragm PPs are basically once-and-done, BB, Long, and multi-disc clutches you can reuse/rebuild the PPs, and marking the index is more critical.
.

They used a dab of yellow paint stick looks like to me. The marks weren’t left on a friction area.I cleaned the surfaces well with brake clean. After only a few miles I also have a chatter I’m hoping will go away after some more driving. I’ve never had one act like this out of the other clutches I’ve replaced.

[MPKind]

Originally Posted by scott70

They used a dab of yellow paint stick looks like to me. The marks weren’t left on a friction area.I cleaned the surfaces well with brake clean. After only a few miles I also have a chatter I’m hoping will go away after some more driving. I’ve never had one act like this out of the other clutches I’ve replaced.

What material is the clutch disc and flywheel? Ceramic can chatter at low RPM and they will chew up cast iron since it's softer than steel. I had the McLeod Super StreetPro with the stock cast FW. It chattered and beat it up too. So a mismatch for sure. That set is no longer in play.

[Schurkey]

Originally Posted by MPKind

Ceramic can chatter at low RPM and they will chew up cast iron since it's softer than steel.

Steel and iron are both nominally a "4" on the Mohs scale But we know that either can be hardened via heat-treatment, cold working, and other processes including alloy elements.

[scott70]

Originally Posted by MPKind

What material is the clutch disc and flywheel? Ceramic can chatter at low RPM and they will chew up cast iron since it's softer than steel. I had the McLeod Super StreetPro with the stock cast FW. It chattered and beat it up too. So a mismatch for sure. That set is no longer in play.

I believe its the super street pro? Disc is ceramic one side organic on the other. All my other clutches have been full organic. Centerforce was the last one and the only time it would chatter was sometimes in reverse but not bad with stock FW...This Mcleod clutch will chatter pretty bad if you try to take off slowly. If you let it out quickly its ok but thats not reality in all around driving. And thats with a new billet mcleoed instead of my OEM FW.

[MPKind]

Steel is more than nominally harder than cast when it comes to flywheels. For daily drivers there's no upside to using steel vs. cast, but with more HP and torque you get more heat. Cast is markedly more brittle than steel and has limits on what it can handle for heat. Ceramic clutches can handle up to 1000F, but a cast FW cannot deal with that extreme coefficient of friction and heat. Micro cracks can occur.

Scott, do you have a cast or steel flywheel?

[scott70]

Last summer I had the set up I’ve always had… original FW, original m21 and centerforce 2 clutch. It went good but I did know for a long time there was visual spider cracks in the FW. End of the summer I installed a new tkx trans, McLeod billet FW and McLeod super street pro clutch. I had the machine shop surface the FW like the instructions said and try to match the balance of the new FW to the old FW. They screwed a weight to the FW that actually came in the clutch kit. When I first started it seemed to have a very slight vibration compared to before. Also noticed it while driving. I took the weight off and it seemed better but I’m still playing with that as soon as I can drive the car again ( spring time). Also I have a chatter now if I try to take off easily riding the clutch normally. I noticed in the McLeod paperwork there’s no warranty on chatter but keep driving it so to see if it gets better. When the chatter starts I throw the clutch in because it’s pretty bad.

[HWYSTR455]

Clutches need to bed just like brake pads, give it a little time before you think about swapping it.

Ceramic takes longer to bed, would have to homework that to determine that.

Discs 'shed' as they bed, and sometimes stuff builds up. If you suspect that, old-timers used to say disengage and lightly slip the clutch a few times to help clear shedded material. No sure if that's true or not, or if it applies to current discs or not.

Marcel also has to cycle a few times before taking a 'set'.

Believe I've had PPs surfaced in the past, even new ones, but a little foggy on that, it's been a while for me.

Hopefully newer parts have better tolerances, but I may be dreaming there.

If a clutch does start to chatter, you should disengage asap. Chatter can cause (or make worse) low, high, and heat spots.

A number of things can cause chatter, contamination, weak springs/uneven clamping, roller/spring hang, uneven surfaces, damaged marcel, worn clutch forks/linkage, incorrect TO for PP, just to name a few. The most common cause is contamination. Or used to be with organic discs.



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[scott70]

Definitely going to try it for awhile this summer before I do anything drastic. If it doesn’t come out of it I’ll have to go through the whole process again with trans removal and all that goes with it. Not looking forward to that since I’m a one man show with no lift. Not sure which maker I’d go with but probably would go back to full organic.

[HWYSTR455]

Originally Posted by scott70

Definitely going to try it for awhile this summer before I do anything drastic. If it doesn’t come out of it I’ll have to go through the whole process again with trans removal and all that goes with it. Not looking forward to that since I’m a one man show with no lift. Not sure which maker I’d go with but probably would go back to full organic.

Which clutch setup do you have now?


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[scott70]

McLeod super street pro… half ceramic half organic 11” diaphragm. Might have 100-150 miles on it since installation

[HWYSTR455]

Well, I'm not a fan of the McLeod diaphram PPs, I think they are hit or miss, and even w ceramic I've heard folks having them slip at even moderate HP levels in the 400s.

Yeah, run it for a while, it may bed and the chatter go away, it's a good course of action.

I'm def curious how you make out, follow up if you can.


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[MPKind]

I purchase the new flywheel and clutch. RAM Billet Steel and a LUK stock clutch. When selecting a new clutch I searched on the forum and discovered to my surprise, that several here on the forum have skipped the metallic/ceramic HD clutches that cost 3X more for a more streetable stock clutch that has been pounded on and held up quite well. Engine will be pulled at the end of the month. Crank will be zero balanced, and that's the end of it.

[scott70]

Originally Posted by MPKind

I purchase the new flywheel and clutch. RAM Billet Steel and a LUK stock clutch. When selecting a new clutch I searched on the forum and discovered to my surprise, that several here on the forum have skipped the metallic/ceramic HD clutches that cost 3X more for a more streetable stock clutch that has been pounded on and held up quite well. Engine will be pulled at the end of the month. Crank will be zero balanced, and that's the end of it.

I’d like to see a update when completed please.