Fidanzza flywheel and transmission 10W60 oil?

[zrss]

Originally Posted by FU2

Bear in mind that the transmission will "growl" loudly with a single mass on the highway when your lugging the engine.
This is my experience at least.

Mine as well. Accelerating from 1500 rpm to 2500 rpm in high gear under wide open throttle produces a loud "whine" or "growl" in both my single mass flywheel Z's. Marc confirmed that the noise is normal.

[Mika73]

Thats good to know. That sound just isnt so nice. Usually helps if rev higher, but problem is worse with cruise that try keep speed something like 50mph or at slow city stop/go traffic.

And 10W60 wont help to this? It helps only at idle?

[FU]

You are using 6th gear at 50 mph ?

[-=Jeff=-]

Originally Posted by A26B

I can maybe understand the possibility of the growl, but not the rattle under load. The rattle is due to the lash in the gear train and should only occur with the clutch out in neutral, NOT while driving under load.

When I first did the Zf swap in my 89, I had the same rattle noise under load.

it was due to the Single mass flywheel along with a NON-sprung hub disc..

the sprung hub disc helped quite a bit to quiet it down

[Mika73]

What's sprung hub disc? I have Centerforce clutch. Don't use 6th gear. Not even at 60mph.

[zrss]

Originally Posted by Mika73

Thats good to know. That sound just isnt so nice. Usually helps if rev higher, but problem is worse with cruise that try keep speed something like 50mph or at slow city stop/go traffic.

And 10W60 wont help to this? It helps only at idle?

10W60 will help a little, but not much. The sprung hub disc will do a lot more to quiet things down. The Centerforce disc you have is not sprung. McLeod used to make a sprung disc - you might check with them if the noise bothers you enough to get you to pull the clutch.

[FU]

A stock flywheel pressure plate and clutch are good till around 550 rwhp & 490 tq. Just FYI.
My LPE-LSV 385 had a Fidanzza flywheel etc. in it. IMO ruined the car. We put the stock setup back in the car. And now it's back to the sweet ride that it once was.

[-=Jeff=-]

Solid hub Disc:


sprung hub disc:

[mike100]

The 10w-60 Castrol BMW oil won't make the gear box sound any different than a 5w-30 based gear lube.

[Paul Workman]

I'm not familiar with the growl you are experiencing. However, upon recommendations from others at the time I installed the Fidanza, I also installed a sprung hub clutch disc as well.

As I recall, the purpose of the sprung hub was to quiet the transmission rattle at idle. I don't recall any discussion about quieting the engine impulses in the transmission when lugging at lower rpm too, but it makes sense, I suppose.

As it happens, the disc I'm using is the disc used on 93-97 LT1 Camaros.

Sprung hub disc part # 381039 (Centerforce) from Summit Racing @ $199.xx

With regard to the pressure plate bolts, the people on this forum that successfully installed the Fidanza also recommended using longer bolts from SRP. The reasoning for that is because the flywheel is aluminum and the longer threads spreads the holding force over more thread area - a good thing when bolting to aluminum.

In addition, the shank on the factory pressure plate bolts fit into a recess at the surface of the flywheel. This is to add a measure of lateral support to resist shearing between the flywheel and the pressure plate. Some have used longer grade 8 bolts from the hardware store, but the shank of hardware store bolts may or may not fit well enough to provide any additional support against shearing.

It is recommended (by the same people that recommended the sprung hub to go along with a successful Fidanza installation) to buy the longer bolts. SRP has the bolts with the proper thread and shank length, and mine came as a kit containing the proper drill bit and thread tap along with the bolts.

FWIW, I did NOT rebalance the flywheel after drilling and tapping it for the longer bolts. However, I did take care to drill the depth exactly the same on each hole. I don't believe I have any vibration issues (e.g., "buzzing") - at least none that I can feel. Maybe I'm just lucky on that one. But, if I had it to do over, I'd probably have it balanced...for peace of mind (at least).

So, to summarize the Net Registry's contributions to the Fidanza installation recommendations for quiet operation with the ZF and the LT5...

• Use a sprung hub clutch disc (mine is the Centerforce #381039 at Summit Racing)
• Use bolts with proper shank and thread length and hardness (SRP has them)
• Balance the flywheel after drilling and tapping the flywheel for the longer bolts (I didn't, but maybe got lucky)
• raise the idle by 100 rpm.
• Replace injectors if the least bit out of spec or marginal function

The result (for mine) is a car that idles and pulls as quiet as it did with the stock flywheel. Even Marc H commented on how nice my Z is to drive. If it is, it is because of the experiences and recommendations I followed from those on the Registry. Nothing against learning by the school of "Hard Knocks", but when possible, I'll try the proven path first.

So, if all this doesn't help, then at least you can probably rule out the Fidanza installation as the cause. That would bring us full circle - back to the transmission.

Good luck. Keep us posted.

P.