Clutch :-(

[Harvie]

Call RAM Clutches, take out the dual mass flywheel and get a steel flywheel with a dual disk clutch/ pressure plate sys with a new HD throwout bearing.

Those will solve all your problems until torque levels exceed 800 ft lbs.

After looking at the pics you can repair that bell housing with Devcon, it does not need to be welded. I could do either and would just use Devcon because it looks like the structural integrity has not been compromised and both would be permanent OEM approved repairs.

If you want to have the bell housing bead blasted and send it to me (Maryland) I will repair it for you for just the cost of the Devcon. You will have a very hard time telling where it was repaired. I have repaired about 15-20 al bells over the years and have a spare ZR1 bell on the shelf to use as a pattern/mold if need be.

or just do it your self.

If the BH is just scarred or chipped repair it with Devcon titanium and it will last forever. Grind the area about 1 inch around the repairable area wit 24 or harsher disc clean off then apply the Devcon low or as close to level as possible.

One or u can smooth the Devcon right after after applying it by using wd40 and a hard steel or plastic surface to make the repaired surface smooth. Then use a clean rag soaked in wd40 wrapped around your finger and gently tap the top to dimple the surface to make it look factory. Once it goes off and sets it takes 24 grit high speed grinder to remove the stuff. It is a perm repair and harder lighter than al.

[Shrek]

Had the same exact problem 3 weeks ago in my wife's track car (stroked LT4)
She was shifting to fourth on the front stretch at VIR when it came apart.
She shut it down immediately and got a tow back to the paddock with no further damage.
I had just installed it from Carolina Clutch and it lasted just over 200 track miles.
The clutch I removed was an 8 year old Carolina Clutch with thousands of track miles on it.
Tom at CC explained the problem (quality issue), apologized, and took care of a correct replacement disc.
BTW we are running an aluminum Fidanza.


From what I understand, the quality issue pertains to the backing plate.
There needs to be a solid backing plate ring, not just the segmented spring steel shown in the photo of ours below.

[Fully Vetted]

Originally Posted by ZZZZZR1

...Downside to the lightweight flywheel, NOISE!! (sounds like a rattle can)...

Mine is dead quite. Corey waved his magic wand over it and that was it.

[c4koh]

All,

Finally had a chance this weekend to remove everything to have a look. Only the clutch bellhousing bolts got me using some bad words, and I expected as much... the rest was fairly straightforward.

Well, for starters, here is what remains of the clutch disk:



The scoring around the outside of the bellhousing is restricted only to the bottom (as already shown in the earlier picture), and is basically a slim, 1mm slice. I'm going to devcon that up and smooth it off with my dremel.

The flywheel (original dual mass) is pretty spotted, and with various scratches ... as would be expected with that amount of broken clutch and back plate spinning around...



And the clutch pressure plate also didn't fare much better:



So.........

I spoke with Tom @ Carolina Clutch and explained it, and I'm going to replace the flywheel (OE DM) with the lightweight aluminum FW, and add to that a Stage 2 clutch kit.

Questions:
Can I re-use the existing 8 bolts from the original flywheel with this new flywheel? Reason I ask is that I saw this:

Originally Posted by Hammer
Thanks to all that have posted regarding the flywheel and clutch. I just got flywheel bolts today. Only thing left for the clutch is the speedometer gears. I'll be ordering them from Marc Monday. I'm installing them and the Hurst shifter while the trans is out on March 13th-14th, then the rear gears April 19th or so.

I had to buy a whole bag (25 ea) of the bolts and washers for the flywheel. I'll be putting up a separate post to sell two sets of them. Probably $12 shipped a set.

This will include 8 - 7/16"x20-1 1/4" Grade 8 Bolts and 8 washers.
Marc Haibeck recommends these as the bolts that come with the Fidanza are too short, 1", and the ones that are stock are too long 2". He also stated the washers are too thin also.

This is the only mention of it...

If I hadn't of read that, I wouldn't have even thought about it... I'd just planned to remove, and re-apply with Loctite 262 Red for those 8 bolts... but that statement got me worried!!

The stock bolt for my 1992 is PN# 10085334 which is 7/16" head (why not a metric size??) and being 2 inches long... ???

Also - flywheel balancing? Tom at Carolina advised it, though with a *maybe* ... I see plenty of posts mentioning folks using the Fidanza who didn't balance it at all (this may not be the same as Carolina's Aluminum flywheel - see here http://www.carolinaclutch.com/ShowIt...0Flywheel.aspx)

I won't get back to the car until the weekend to take the flywheel off, but Tom mentioned if it's balanced with only a few (1 or 2) weights, then likely I'd be fine using the new FW as-is... but if it has 3 or more, I'd need to balance it...

So - any info on whether I can re-use the 8xFW bolts and new LW FW balancing appreciated...

[Harvie]

1) I would rec you research the differences between steel and al flywheels very carefully. I use a single heavy steel with center force clutch sys currently in the LT5 and will repalce with dd when it fails.. Reason: In my 8.5 bracket car we tried AL and after 3 failures we went back to a heavy steel NON FACED . WE ALWAYS BALANCE ANYTHING THAT SPINS FASTER THEN 4500 RPM. 3 seaons later not one more flywheel failure. We shift at 9200 and have dual discs and the flywheel failures have been 100% eliminated. Ram makes our flywheels currently. Hayes also makes great clutch system for the LT5.

A dual disc system with a bullet proof tob is the current tech for these cars now..Ram or Hayes make the complete systems

You will find that a car with a heavier spinning flywheel vrs a lighter weight faced flywheel will maintain the rpms better when starting and between shifts. The dics will take the beating instead of the crank and thrust bearings, as all clutch systems are designed to accomplish.

2) Also get new higher grade flywheel fastners then even the vendors rec, ARP and Crower make them, these are one of the weak points in all the systems. The vendors default down to grade 8 and it is a cost saving that is not worth the gamble. ALSO GET HIGHER GRADE PRESURE PLATE BOLTS most forget those. My flywheel bolts are grade higher than grade L9 but those L9 (all the way) should do for a small block Chevy and will never fail.

PS I never reuse any high grade fastner after it is torqued (the bolt stretches) and can never give the same strentgh bond. Cheap Ins...

I play around with a 3400 lb cars with 850-900 FT lbs of torque with 1150+ HP to 1400Hp punishing clutches and have learned a few expensive things about clutch systems. Now lets talk about air shifters.....

[Daniel_Mc]

I would not reuse the bolts. See "torque to yield" for me it's cheap insurance to just change the bolts.

Going back in my notes on the Z I installed ARP #230-7303 (had to order 3 packs), the bolts came with the washers needed. Lots of miles later and no issues thus far. BTW the ARP's are torque converter bolts but are what you need.

Best of luck in your repairs!

-Daniel

[Harvie]

Originally Posted by Daniel_Mc

I would not reuse the bolts. See "torque to yield" for me it's cheap insurance to just change the bolts.

Going back in my notes on the Z I installed ARP #230-7303 (had to order 3 packs), the bolts came with the washers needed. Lots of miles later and no issues thus far. BTW the ARP's are torque converter bolts but are what you need.

Best of luck in your repairs!

-Daniel

If you would like you may always call ARP and get the product code for the single fastner you need along with THE HARDNED STEEL WASHERS, then call any speed shop or jugs/Smuuit and order just what you need...

OR


The scrounges like me, get the numbers then check the nascar guys or arp bolts.com / ebay, they sell them a whole lot cheaper.

[c4koh]

Harvie, Daniel,

Thanks for this info. The ARP bolts are shorter than the 2 inch bolts that I have, but shorter of course will fit... 3 packs... that's nearly $50 for 8 (or well, 9!) bolts....

[c4koh]

OK, I've used boltdepot before to good use.

Looking at the spec of the ARP Bolts... these:

http://www.boltdepot.com/Product-Det...px?product=758

look correct - Grade 8, 7/16"x20 (fine thread) 1.25" ... and way cheaper (even buying 25...)...

[Harvie]

Originally Posted by c4koh

OK, I've used boltdepot before to good use.

Looking at the spec of the ARP Bolts... these:

http://www.boltdepot.com/Product-Det...px?product=758

look correct - Grade 8, 7/16"x20 (fine thread) 1.25" ... and way cheaper (even buying 25...)...

Grade 5 or used ones off ebay are even cheaper, after all its only a chevy....

You guys are lucky you have those little bitty bolts, just one of my Crower TI rod bolts costs more than all your flywheel and pp bolts combined.

Yup $116 each rod bolt.....that is 2 of those into the about $900 each connecting rod. But they are pretty.

If you do use grade 8, just bookmark this page so when it blows, you have direct link to all the part numbers to get the new stuff....