Car was making a strange noise last weekend. Took it apart this morning and found that the aluminum flywheel was loose. The bolts were loose and it was crack around the bolt circle so its trashed.
Not putting it back together without a twin disk setup.
Car was making a strange noise last weekend. Took it apart this morning and found that the aluminum flywheel was loose. The bolts were loose and it was crack around the bolt circle so its trashed.
Not putting it back together without a twin disk setup.
this is the second time you've cracked one like that isn't it?
this is the second time you've cracked one like that isn't it?
I cracked a steel one like that but the bolts were still tight. After That I got a SFI harmonic balancer. I guess that was needed for the auto guys to stop cracking their flexplates. My clutch has been "slipping" for a couple months now. When it does it makes a crazy vibration throughout the whole car. When it slips it still pulls hard, the rpms would jump up over the torque curve then catch up and hold fine in the upper rpms. (if you can image that)
I think the vibration caused it. Unless I forgot to put loctite on the bolts which I would find very hard to believe.
Hmmm... it's possible the aluminum under the bolt heads experienced creep thereby relaxing the tension on the bolts. But it's also possible if you're truly running 800 lbft of torque with stock flywheel bolts and bolt torque that you may be close to exceeding the clamping force of the flywheel to the crank flange.
It was good and tight two months ago with I took it off after I broke the diff in my trans. I took it off because the insert was warped. (insert appears to be fine this time) The markings looked the same from the bolt heads. https://www.fiero.nl/forum/F.../103440-13.html#p490
How thick is the flywheel at the crankshaft flange bolts? With 8 bolt holes the smallish crankshaft pattern, there isn't much material left around the bolt pattern. Making the flywheel thicker around the crankshaft bolt pattern with the bolt holes as small as possible would help, but you might want to consider a billet steel flywheel.
At that power level, you might want to consider taking the engine apart and having everything balanced together.
Here is the one California Kid used in twin disk configuration - rated at 750 lb-ft:
I doubt there will be a button flywheel for a 3800 as an off the shelf item, but it wouldn't hurt to call Tilton or QuarterMaster to find out. Without a button flywheel, you will need to get a new flywheel (billet steel would be my recommendation) and have it drilled/tapped for the bellhousing pattern for the smaller clutch. You will need to check/verify stack height of the flywheel/pressure plate/clutch fingers as well and make sure the clutch surface on the flywheel has a smaller ID than 5 1/4" so the disk will make full contact.
If you have to step up to a triple disk clutch, you will likely have to add a spacer between the engine and transmission to gain enough space for it to fit.
You might also check out McLeod RST 9 1/2" twin disk clutches... I kinda doubt they will clear the F23 differential and they might still be too tall, but its worth a look.
I took some measurements. From the crank to the HTOB (fully compressed) I have 2.75". At that depth I have 9" until it will make contact with the diff. The diff slopes out of the way from there up. The 7.25" twin disk should fit nicely if I can get a flywheel made to accept it.
I do have this crazy custom looking flywheel that I found on a 3800. It measures 0.700" from crank to clutch surface but the ID of the flywheel surface is 5.75"...darn.
What do you guys think about have a button flywheel remachined or custom made with the 8 bolt 3800 pattern. I could bolt that to a factory flex plate to get the ring gear and the balance-offset that the engine requires?
Im not that big a motor guy on newer stuff. Out of curiousity why are you going to a 2 disk clutch ? Ive never had any issue at all with even V8s over 400hp using a stock OEM clutch. What kind of engine in a Fiero has 800 ft pnds of torgue ? My 454 7 ton motorhome dont have half that. Not to start any arguments, just interested.
Im not that big a motor guy on newer stuff. Out of curiousity why are you going to a 2 disk clutch ? Ive never had any issue at all with even V8s over 400hp using a stock OEM clutch. What kind of engine in a Fiero has 800 ft pnds of torgue ? My 454 7 ton motorhome dont have half that. Not to start any arguments, just interested.
he is running 10's. big turbo on a built-ish 3800, needs holding power if you're really gonna lean on it. a twin disc can also be more streetable than a comparable single.
Im not that big a motor guy on newer stuff. Out of curiousity why are you going to a 2 disk clutch ? Ive never had any issue at all with even V8s over 400hp using a stock OEM clutch. What kind of engine in a Fiero has 800 ft pnds of torgue ? My 454 7 ton motorhome dont have half that. Not to start any arguments, just interested.
What do you guys think about have a button flywheel remachined or custom made with the 8 bolt 3800 pattern. I could bolt that to a factory flex plate to get the ring gear and the balance-offset that the engine requires?
I would go custom made so you can have as much material as possible between the 8 bolt holes, unless you find one with a much larger pattern so the minimum material is still the same. Using an auto flex plate and button flywheel is pretty common with these twin clutches.
What do you guys think about have a button flywheel remachined or custom made with the 8 bolt 3800 pattern. I could bolt that to a factory flex plate to get the ring gear and the balance-offset that the engine requires?
Tilton has MUCH better engineering data on their clutches on the web than QM does.
QM used to make a bolt-in twin disk that fit the Muncie 4 speed and V6 (6 bolt crank pattern).
There isn't enough room inside the F23 or 282 bellhousings to stack a button on top of the stock flexplate. You'll have to bore the center out of the stock flexplate and WELD a button into it. MAKE a flywheel, basically.
I analyzed fitment of a Tilton 7.25" dual disk clutch in my Northstar/282 car. The bolts that hold the diaphragm spring to the pressure plate cover need to be flipped because there isn't enough room for the nuts on the outside. They hit the output shaft bearing boss inside the bellhousing. You end up with a max thickness of about .450" from crank flange to friction surface for the button. That's pretty thin. That will be slightly different for the F23, but will be in the same ball park.
Once you fit the clutch, you need to rework the hydraulics because it has a 500+ lbs throw out load, but only .250 throw out travel to disengage.
just a thought, I know L67's are crazy popular down under in Australia, any chance a flywheel already exists?
maybe... RWD bellhousings are typically deeper than the 282 & F23 bellhousings... more like the F40's, which means a lot more available thickness for a flywheel.
Ahhh, OK gotcha. Its a racecar. I thought they might be on street cars with like just a bolt in 3800 even supercharged. I know older Bonnevilles barely had 250 hp even with those. My 383 v8 auto always snapped axles...3 of them till Archie hooked me up...and those were also with 3 blown transmissions. . I know some go for the high end 'gimmicks' just for appearance like drilled/slotted rotors (on a 4 cyl Duke).
Ahhh, OK gotcha. Its a racecar. I thought they might be on street cars with like just a bolt in 3800 even supercharged. I know older Bonnevilles barely had 250 hp even with those. My 383 v8 auto always snapped axles...3 of them till Archie hooked me up...and those were also with 3 blown transmissions. . I know some go for the high end 'gimmicks' just for appearance like drilled/slotted rotors (on a 4 cyl Duke).
He races it, but my understanding is this car see a ton of street miles. which would be a distinct advantage to a twin disc, they can provide much more hold, with comparable or less pedal effort.
your 383 also ran low 9's didn't it...
[This message has been edited by ericjon262 (edited 08-27-2014).]
maybe... RWD bellhousings are typically deeper than the 282 & F23 bellhousings... more like the F40's, which means a lot more available thickness for a flywheel.
I was thinking that may be the origin of our mystery flywheel above.
I was thinking that may be the origin of our mystery flywheel above.
Mystery flywheel came from a 282 application, it seems to be custom made to some degree....
Although the aussy land cars may have solutions for us, they use a dual mass flywheel stock.. so most you'll find there is an overly thick billet flywheel. Even if you found something worthwhile, performance parts from aus cost an arm and a leg over what they would typically cost here... and there is the issue of extreme shipping costs.... It would be very hard to find something economical there when the machine work involved with grinding out a custom "button mount" and glueing a starter ring on it is not that tough.
I was thinking that may be the origin of our mystery flywheel above.
quote
Originally posted by darkhorizon:
Mystery flywheel came from a 282 application, it seems to be custom made to some degree....
It *looks* a lot like the QM flywheel for the aforementioned bolt-in dual disk for the Muncie. However, at .700 thickness, it's too thick to use a dual disk in the F23 or 282, but not as thick as the production longitudinal flywheels. Also, at 5.75" ID of the friction surface, it's too large in diameter for the normal 7.25". My guess is it's set up for an 8.5" single disk in a FWD transmission.
[This message has been edited by Will (edited 08-26-2014).]
The mystery flywheel had a stock organic clutch bolted to it.
I took some more measurements. The flexplate is .105" Crank bore 1.260" Crank to highest point in the bellhousing is 3.005" Crank to compressed htob is 2.780"
I put about 3500 hard miles on it in the summer and about 1000 miles in the winter. When I broke my first stage 5 clutch from spec they told me it wasn't for street use... I'm hoping the twin disk will be a lot tamer on everything.
Ahhh, OK gotcha. Its a racecar. I thought they might be on street cars with like just a bolt in 3800 even supercharged. I know older Bonnevilles barely had 250 hp even with those. My 383 v8 auto always snapped axles...3 of them till Archie hooked me up...and those were also with 3 blown transmissions. . I know some go for the high end 'gimmicks' just for appearance like drilled/slotted rotors (on a 4 cyl Duke).
Yes, I still am running the QuarterMaster 7.25 Pro Series in double disk configuration, flywheel is custom made steel w/tool steel insert at load surface, it has same holes in it that hold Clutch Assembly to flywheel. The only change I've made with it a couple years back was switching to their Metal Clutch Disks. The main reasons for changing to metal was that the organic didn't last too long (about 12,000 miles), secondly once there is some wear with organic it will slip just a bit, and that generates a lot of heat. That heat will permanently distort a flywheel insert plate, and also the steel floater plate between disks, either area can only accept .006" distortion before you torque holding is severely compromised.
The twin metal disks raise the torque holding power to slightly above 800 ft. lbs of torque, and because the grip so well, very little heat in generated. Even with more grip the metal disks setup is drivable on street with no chatter. By looking at pictures you posted, I'd say that you had severe heat generated by slipping that caused all the damage.
These are the Metal Clutch Disks that I use:
As Will stated, you would have to get a special flywheel built for the QuarterMaster setup (I don't believe a flex plate design would hold up in your case). Can't offer any advice on Tilton, have no experience with them. QuarterMaster will work with you, but it isn't going to be cheap. The main reason I have stayed with them is that it works and the 5 spd Getrag is tough to package a great clutch it.
Here's a picture of my old flywheel insert plate when I was using their organic disks. This is what happens once you start to notice just a little slip and drive it a little longer. Note slippage generated heat, warped plate, more severe heat caused heat fractures:
Edit to add: You'd better seriously think of adding a scatter shield behind your back seat.
[This message has been edited by California Kid (edited 08-27-2014).]
flywheel is custom made steel w/tool steel insert at load surface,
I think that's part of your problem, as you'll get less heat conducted away from the friction surface vs. a 1 piece unit. That results in higher temps and more distortion in the friction insert.
quote
Originally posted by California Kid:
(I don't believe a flex plate design would hold up in your case).
Since QM doesn't make the flywheel anymore, a modded flexplate with the button welded in is the only practical option for a 282.
However, since the F23 has more room in the bellhousing, he can stack a button on top of a flexplate and bolt everything together just fine.
I understand what you are getting at, but the heat issue was with the QM's Organic Disks which I don't use anymore, QM's metal disks grab a like glue, and don't generate heat experienced with the organic compound. That and I'd rather be replacing an insert plate when needed than having to replace flywheel, and re-balance the whole rotating assembly. So far I've had no issues with the new parts.
I understand what you are getting at, but the heat issue was with the QM's Organic Disks which I don't use anymore, QM's metal disks grab a like glue, and don't generate heat experienced with the organic compound. That and I'd rather be replacing an insert plate when needed than having to replace flywheel, and re-balance the whole rotating assembly. So far I've had no issues with the new parts.
I never said it didn't grab better. The major factor in how easy to modulate a clutch is, is the compressibility of the friction material. The metal friction material is much less so than the organic and makes the clutch more like an on-off switch.
. I know some go for the high end 'gimmicks' just for appearance like drilled/slotted rotors (on a 4 cyl Duke).
