Switched to RAM dual-disc clutch, some questions

[A26B]

Originally Posted by Jagdpanzer

I've had the same experiences with the Ram DD I installed a few months ago. The ZF gear rattle became to much to live with so I'm replacing the aluminum FW with a heavier steel version from Ram. To address the high pedal and clutch smell I will be installing the pedal height adjuster dashpot Ram offers in the clutch line.

Phil,
I can special order the billet steel flywheel for the RAM dual disc clutch for you.

Let me know if I can assist.

[Pete]

No worries as you get older you won't hear as much

Have these on 3 FBI Z's
I have the prototype on my Z since i did the R&D on this with my friend Bob's connects this one is a bit louder and rattles a bit more but then i have big cams.

The other 2 are big inch LT5's w/cams same set up as yours and really not that bad, they are as if you installed Fidanza Alum flywheel.

If you have stock idle (650rpm) try raising idle a bit to 750

Pete

[XfireZ51]

I suspect part of the noise issue is the change in mass for the dual clutch mechanism etc. creates a requirement for re-tuning. At the very least, it would be interesting to datalog a before and after. Having installed 2 Fidanzas on different motors, the tune for idle needed to be changed. Interesting that you are also getting a rattle even when on throttle.

[c4koh]

I am not sure what the weight of the RAM Aluminum Billet flywheel is compared to the Fidanza, but in any case for sure it's lighter than the OE dual mass and pressure plate, so I imagine that there will always be some noise.

My questions were more about why I get a ticking when cold - it's a noticeable RPM-related tick-tick-tick that only happens with the clutch engaged (pedal out), and goes away 2-3 minutes into driving... it's get quieter, and quieter over a few minutes of driving, and disappears...

Seems like the noise through the ZF is just a factor of the change in mass, and nothing to be concerned about.

Slight clutch smell - is it a breaking-in phase or is it just a symptom of the new setup?

I should also have asked: in my stock application, the clutch was pretty much sealed, with the exception of the flywheel inspection cover, it was pretty airtight with the slave cylinder in place... now I have just the SS hydraulic lines, perhaps there's just less air-tightness, allowing the slight smell to escape... ??

Anyway, as I said in my first post, the clutch visibly (if I look at my inspection hole made to fix the hydraulic bearing onto the guide) engages and disengages, so other than my comments, I cannot feel / see / notice any problem...

Just learning the new setup, I suppose...

[Jagdpanzer]

Originally Posted by c4koh

I am not sure what the weight of the RAM Aluminum Billet flywheel is compared to the Fidanza, but in any case for sure it's lighter than the OE dual mass and pressure plate, so I imagine that there will always be some noise.

My questions were more about why I get a ticking when cold - it's a noticeable RPM-related tick-tick-tick that only happens with the clutch engaged (pedal out), and goes away 2-3 minutes into driving... it's get quieter, and quieter over a few minutes of driving, and disappears...

Seems like the noise through the ZF is just a factor of the change in mass, and nothing to be concerned about.

Slight clutch smell - is it a breaking-in phase or is it just a symptom of the new setup?



I should also have asked: in my stock application, the clutch was pretty much sealed, with the exception of the flywheel inspection cover, it was pretty airtight with the slave cylinder in place... now I have just the SS hydraulic lines, perhaps there's just less air-tightness, allowing the slight smell to escape... ??

Anyway, as I said in my first post, the clutch visibly (if I look at my inspection hole made to fix the hydraulic bearing onto the guide) engages and disengages, so other than my comments, I cannot feel / see / notice any problem...

Just learning the new setup, I suppose...

I also had a ticking noise, or to be more precise a screeching noise. Turned out to be the valley drain tube rubbing on the front side of flywheel. A few love taps with a hammer and piece of wood solved it.

[Bob Eyres]

I have had a Rippie 15lb. flywheel, (machined down GM stock single mass Camaro unit), for a long time. It has given good service, but rattles badly.

The reason I mention this is that I believe the rattle is not directly proportional to the weight of the flywheel, and getting a slightly heavier flywheel wouldn't necessarily cure it.
Mine rattles up to 2,500 rpm in 1st gear.

Q?- Do these dual disc units hold up to the big inch LT5's? (Not that I have to worry).

[5ABI VT]

I think dual discs by nature rattle twice as much as a single. The holding power is much greater though so it's a trade off. I have a McLeod street twin on my 93 and it rattles at low rpm on throttle but it sounds glorious with the B&B, solid roller valvetrain racket and big cam.

I also agree the weight of the flywheel in my opinion won't matter much. A smooth idle will help and raising the idle rpm will also help. Sometimes a very slight change in idle rpm is enough to keep things smooth and quiet down the gears in the trans. I know with my 93 I played with rpm at idle and the difference was from tank like ticking to totally quiet (700 vs 900)

[XfireZ51]

Has anyone ever put scantool on these to see if the rattle is inducing knock retard?

[Bob Eyres]

Originally Posted by XfireZ51

Has anyone ever put scantool on these to see if the rattle is inducing knock retard?

Great question. I'd like to know the answer to that.
I'd like to have a switch to shut off all knock retard when using 110 octane gas at the track. What could go wrong?)

As to the rattle, I don't think that can be attributable to the dual disc. The rattle is caused by vibration from the engine transmitted to the input shaft of the trans. This is only when the clutch is engaged and the whole assembly vibrates as a unit. So, vibration wise, the dual disc wouldn't react any differently than a single disc when engaged.
The only thing that can alleviate that rattle is a dual mass flywheel, (or a smoother idle).

[rkreigh]

you would think the gear knock would drive the knock sensor crazy but they seem to be tuned to a different frequency or something and I don't see any knock at all

does sound like a woodpecker trying to get out of the tranny though

I've contemplated going back to a stock dual mass as the gear rattle is beyond annoying on the big cam cars and having a bit heavier flywheel is better for driving on the street

especially with stock gears.

I do like the way the old LSV winds up when provoked with it though!