My Northstar killed its first clutch, a DF201502, the clutch Archie recommends for use with his kits.
I was driving home and turned onto my street. Almost nobody lives on it, and it was a cold day with everyone inside so I didn't have any qualms about romping on the car. I shifted into 2nd and put the pedal on the floor. As the RPM was getting to about 6000 a noise like a handful of ball bearings in a paint mixer erupted behing my head. I popped it into neutral and let the engine come down to idle. The noise was still there, and matched the engine's RPM. Thinking I might have grenaded a lifter I killed the engine and coasted into my driveway. After saying !@#$ to myself for several minutes, I got out the stethoscope and cranked the engine back up. To my relief (sort of) the noise was coming from the bellhousing.
Conveniently, I have this week off. I just got the clutch out this morning and found that one of the straps that holds the pressure plate casting to the pressure plate cover had snapped right at the pressure plate casting end and pulled its rivet out with it, or possibly vice versa. The strap was out a little bit and folded over on the end as though it had been dragging the inside of the bellhousing, and the rivet had been bouncing around inside the bellhousing.
I shipped it to Centerforce for them too examine.
I have pictures, but they're too big for PIP. If anyone is willing to re-size them for me, I'd be happy to post them.
------------------ '87 Fiero GT: Northstar, Getrag, TGP wheels, rear sway bar, rod end links, bushings, etc.
[This message has been edited by Will (edited 01-21-2003).]
IP: Logged
05:48 PM
PFF
System Bot
PBJ Member
Posts: 4167 From: London, On., Canada Registered: Jan 2001
Kewl. Not to make light of it, but it sounds like a mess. This issue is of real interest to me, as I'm going with the exact setup. I already have the CF DF clutch you recommended (201502). Post pics and keep us informed.
So then, does the N* have more punch than the SBC?????
IP: Logged
07:57 PM
LoW_KeY Member
Posts: 8081 From: Hastings, MI Registered: Oct 2001
Kewl. Not to make light of it, but it sounds like a mess. This issue is of real interest to me, as I'm going with the exact setup. I already have the CF DF clutch you recommended (201502). Post pics and keep us informed.
So then, does the N* have more punch than the SBC?????
Northstar might have a little more umph then a LM1 (240 HP) you figure SBC are endless power if you want them to be along with $$.
I was thinking about this clutch setup as well with the 3800SC.
------------------ -KC
1988 Formula 3800SC performance build up begins Feb 15th AIM: FierFormula88, Yahoo!: low_key_02
IP: Logged
08:19 PM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
Years back two different high performance Centerforce clutch setups were tried in my car and both had their centers tore out in under 500 miles. Went through 5 different manufacturers before finding QuarterMaster to hold up to the torque of my beast.
I was thinking about this clutch setup as well with the 3800SC.
"Northstar might have a little more umph then a LM1 (240 HP) you figure SBC are endless power if you want them to be along with $$."
I think a fair more than a motor w/240 hp. Isn't anything capable of endless HP/torque with enogh $$? CHRFAB sells 'em (N*'s) with 1200 hp for several thousand $$.
IP: Logged
08:57 PM
I'm Back Member
Posts: 3780 From: Phoenix, Az, USA Registered: Oct 2002
Sounds more like it was the revs that killed it, not necessarily the power.
Can't wait till the results come back from CF to see what the problem was. Could well have been the revs though. A dual clutch setup is definately the clutch of choice for the N*, as its smaller in diameter and less susceptable to high revs.
IP: Logged
09:01 PM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
PBJ: pictures sent. Hope you have a lot of bandwidth Thanks.
Torque killed it. The straps are under tension when forward torque is applied to the clutch, and it sure looks like the strap just experienced too much tension. I wasn't even turning much RPM. 6000 really isn't that extreme, and my engine is currently limited at 6400. It does see the limiter daily, though
The clutch had been in for 13 months, driven hard for 8 months and had accumulated about 15,000 miles. I don't know what Centerforce is going to say about it.
On the plus side, it never slipped
Considering I'm "only" putting 267 ftlbs to the ground, I doubt it's anything but a manufacturing defect. However, I'm very familiar with Murphy's law, and am currently solving my non-linear waterfowl problem so that if this happens again I can just plop a Quartermaster Carbon V 5.5" clutch. I haven't decided if I can fit the 3 disk in, or if I'll have to stay with the 2 disk. Decisions, decisions...
[This message has been edited by Will (edited 01-21-2003).]
IP: Logged
09:31 PM
Fierobsessed Member
Posts: 4782 From: Las Vegas, NV Registered: Dec 2001
Yep, those straps get pushed on, the harder you step on the gas the more those straps push the pressure plate into the clutch disk. If one bends slightly when enough torque is applied, snap. Note to self: be weary of centerforce pressure plates.
------------------
"How do I get one of those Smileys that rolls back and forth accross the screen?" -Archie
IP: Logged
09:40 PM
PFF
System Bot
Her86GT Member
Posts: 1173 From: Ontario, Canada Registered: May 2001
PBJ: pictures sent. Hope you have a lot of bandwidth Thanks.
Torque killed it. The straps are under tension when forward torque is applied to the clutch, and it sure looks like the strap just experienced too much tension. I wasn't even turning much RPM. 6000 really isn't that extreme, and my engine is currently limited at 6400. It does see the limiter daily, though
The clutch had been in for 13 months, driven hard for 8 months and had accumulated about 15,000 miles. I don't know what Centerforce is going to say about it.
On the plus side, it never slipped
Considering I'm "only" putting 267 ftlbs to the ground, I doubt it's anything but a manufacturing defect. However, I'm very familiar with Murphy's law, and am currently solving my non-linear waterfowl problem so that if this happens again I can just plop a Quartermaster Carbon V 5.5" clutch. I haven't decided if I can fit the 3 disk in, or if I'll have to stay with the 2 disk. Decisions, decisions...
[This message has been edited by Will (edited 01-21-2003).]
Ya, the stock motor turns 6k, so what's the biggy with that? It seems the 3.8SC guys are always looking to run down the N*. I would love to get a race going with representations from all motors.
I figure that's about average for a 5-speed Fiero N*; 1 year, 1 clutch assy.
IP: Logged
10:40 PM
I'm Back Member
Posts: 3780 From: Phoenix, Az, USA Registered: Oct 2002
The pics are pretty self-explanatory. The strap did not slice the head off the rivet. The rivet is intact, although abused. It just pulled out of its hole.
IP: Logged
11:50 PM
Jan 22nd, 2003
wcapman Member
Posts: 208 From: Gulfport, MS USA Registered: Dec 2001
One more word. I'm running the quartermaster dual disk clutch with a N*/Getrag. It doen't slip, hasn't failed. Its been running since 1998. Gets autocrossed and hard street driven. No problems. Probably 20,000 miles.
Don't think the three disk clutch is necessary or will fit. You want to be able to feel the clutch and the 3 disk is much more in/out.
Dan has the same setup as I do and has been running since 1999. He now has 25000 miles on his and I KNOW he runs it hard. He did replace the clutch disks about 5000 miles ago because the tranny leaked oil on the clutch. But there was plenty of disk left.
One other word on the QM, it is VERY light weight. Revs come fast. Smaller diameter also means it is less likely to grenade at hight r's.
I say we should all thank Getrag. That the tranny holds up is to me the miracle.
IP: Logged
12:06 AM
StansGT Member
Posts: 914 From: Schoolcraft MI, USA Registered: Jul 2001
Centerforce will probably say that there was no fault in the clutch assembly and will fix the problem once, but if this happens to the clutch again, they will not warrenty the problem. My 3800sc Grenaded a DF clutch that was the archie version, and they basically found no fault in the pressure plate and sent a new one to me, but along with the new plate, they included a note saying they wouldnt cover anything that happened in the future unless they felt it was the fault of the assembly!
One more word. I'm running the quartermaster dual disk clutch with a N*/Getrag. It doen't slip, hasn't failed. Its been running since 1998. Gets autocrossed and hard street driven. No problems. Probably 20,000 miles.
Don't think the three disk clutch is necessary or will fit. You want to be able to feel the clutch and the 3 disk is much more in/out.
Dan has the same setup as I do and has been running since 1999. He now has 25000 miles on his and I KNOW he runs it hard. He did replace the clutch disks about 5000 miles ago because the tranny leaked oil on the clutch. But there was plenty of disk left.
One other word on the QM, it is VERY light weight. Revs come fast. Smaller diameter also means it is less likely to grenade at hight r's.
I say we should all thank Getrag. That the tranny holds up is to me the miracle.
Would you happen to have some info on the quartermaster unit you used?
Thanks! JM
[This message has been edited by Slammed Fiero (edited 01-22-2003).]
IP: Logged
09:56 AM
LS1swap Member
Posts: 1181 From: McHenry,IL.USA Registered: Jan 2001
Hey will sorry to hear that at least it did grenade the clutch. Say while it is apart could you take a pic of the starter. Just curious what they look like sitting in the valley.
If they'll send me a new one, I'll put it in, but getting the QM setup ready just got bumped up on my priority list. The next time this happens, I'll just change it out for the QM and start my own "Wall of Shame"
I know the 7.25" organic setup is in use and is a known quantity, but I'd like to try the Carbon 5.5" just to be different, and because carbon clutches are cool Comparing setup heights listed by QM to the setup height I measured for the stock clutch, I don't think I'll have enough thickness left over for a button on which to mount the 3 disk clutch, but I should have plenty of room for the 2 disk. The remaining questions are whether or not that clutch can use the Getrag throw out bearing, and whether or not the hub for the carbon clutch is available with the Getrag spline.
IP: Logged
10:23 AM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
Hey will sorry to hear that at least it did grenade the clutch. Say while it is apart could you take a pic of the starter. Just curious what they look like sitting in the valley.
I emailed you a pic. If you look at the pics of the Getrag bellhousing, you can see the mod I had to make to clear it. Can't see any more of it than this because it's under the intake manifold, and I'd just as soon not remove that.
IP: Logged
10:37 AM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
I talked to a Centerforce tech today. They're going to send me a new pressure plate with doubled straps and a new disk. My old disk was serviceable, but the rotation stops which prevent the hub springs from coil binding were pounded down by 1/8" or so.
They're NOT going to replace it again, however.
And I've got ANOTHER 500 mile break-in to suffer through.
I used to recommend this clutch because of its streetability and ability to hold power, but now I'm not so sure. Now that I'm experienced with it, I've found that it engages gradually, but it chatters. It can hold the torque, but it can't take abuse. It's obviously at its limits with even a moderate V8 like the Northstar.
I don't have any personal experience with the SPEC cluchtes, but I've heard good things about them.
Originally posted by Will: I used to recommend this clutch because of its streetability and ability to hold power, but now I'm not so sure. Now that I'm experienced with it, I've found that it engages gradually, but it chatters. It can hold the torque, but it can't take abuse. It's obviously at its limits with even a moderate V8 like the Northstar. I don't have any personal experience with the SPEC cluchtes, but I've heard good things about them.
Will, sorry to hear you blew up your clutch already. As far as the SPEC goes, if a Stage 3 can stand up to me and the motor in my car--I can't break the mofo for the life of me and it doesn't chatter or slip--with three more stages available above that......
There's currently three of us with SPECs on the road (jimmy & gtbastard), and last I heard four more are under construction (tesmith, chester, fierolt1, rbeaubien).
Will, I know the QM is the typical high powered fiero thing to do but, I would give Tilton a call before ordering that. They're just on a whole other level and I found them to be very helpful. QM's reps didn't seem to even want to talk about their product.
IP: Logged
07:05 PM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000
I'm keeping my options open. I'm also considering the Tilton carbon multi-disk clutch.
I'd go with the SPEC, except that I'd have to pay for it, while the CF replacement is free, and should last me long enough to get the Tilton/QM unit installed.
Even if I paid for the SPEC, it wouldn't be a final solution. The SPEC might not come apart at 8500+ RPM, but I have no faith in the stock cast iron flywheel's ability to turn that fast and stay together. That's why I'm set on the Tilton or QM.
[This message has been edited by Will (edited 01-22-2003).]
IP: Logged
07:08 PM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
Will, regarding the QM 5.5 setup, look closely at the clutch surface inside dimension of 3.90". Don't know what the flywheel bolt circle dia is on the "N" flywheel, but know it would require a special steel ring insert to cover bolt heads on SBC flywheel.
Wish they made the 7.25 setup with single hub design, would save the frustration of lineing up two disks to install trans (no pilot shaft available for custom setup).
IP: Logged
07:20 PM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
The thing that attracts me to the carbon/carbon setups is that the flywheel is NOT a friction surface. It just supports the end floater disk, which takes the wear.
I just took some measurements from the Getrag TOB. It looks like it won't fit inside the cover of anything but the 7.25" models from each manufacturer.
Perhaps the easy solution is to use the matching 4T80E 4 speed auto tranny with the Northstar. It was designed for Northstar compatibility and should last a long time.
IP: Logged
07:58 PM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
Originally posted by Dennis LaGrua: Perhaps the easy solution is to use the matching 4T80E 4 speed auto tranny with the Northstar. It was designed for Northstar compatibility and should last a long time.
Damn, I didn't even see that stupid yet oh-so-predictable remark from Dennis coming that time!! Where's the "Ignore Dennis" button on these transmission/clutch threads, Cliff??
IP: Logged
08:26 PM
California Kid Member
Posts: 9541 From: Metro Detroit Area, Michigan Registered: Jul 2001
Perhaps the easy solution is to use the matching 4T80E 4 speed auto tranny with the Northstar. It was designed for Northstar compatibility and should last a long time.
Actually, the easy solution is to slap a new clutch in and put the car back together Using the 4T80E at this point would require fabricating mounts, setting up axles, rewiring, rechipping, changing the shifter, steering column, pedal box, etc. and would not be easy at all.
IP: Logged
09:26 PM
Will Member
Posts: 14249 From: Where you least expect me Registered: Jun 2000