MAGK944

Reading on here it seems that lightening the flywheel on our cars has a negative effect, less torque and drivability issues at low rpm's. Great for a track car but not for a mainly street driven car.

Those that have lightened the stock flywheel or fitted an aftermarket lighter flywheel have any feedback?

Techno Duck

Non issue on my 951. Rev's drop a little faster but i like it. Havent noticed it being any harder to work the clutch in traffic either.

Only downside i have noticed is if you are on it hard at high RPM and clutch in without shifting (coasting), the car will stall on occasion.

choinga

...my PO put a Fidanza in my car when he swapped the clutch and I hate it. 3 years later it's still a PITA to drive. In my car it's either on or off...no one...and I mean no one that has driven it has gotten it out of first without stalling it once. The other thing I don't like is the downshift clutch chatter...

If I had it do over again, I wouldn't do it - for street driving I just don't see the point and with a setup like mine it makes the car undriveable for anyone who doesn't have some experience with it. I won't let anyone drive my car (wait, this might actually be an upside... ) because I know they'll get themselves in trouble with it.

When I bought it - I drove it back from DC...so I had about 1400 miles of experience with it by the time I got home...but I stalled the damn thing about 10 times before I made it to my driveway.

YMMV...I'm not 100% sure of all the particulars but it's a SPEC clutch and a Fidanza flywheel - no idea what weight, etc...

Techno Duck

BTW, i should mention i am using a lightened stock flywheel. Weight came in around 9lbs i think. the ~6lb Fidanza is overkill i think.

951Saga

I found this one on ebay a few years back… lightened to about 9lbs. The only problem I had was dropping it on my big toe!

On my 951 its great combined with the stock PP and a 930 disc. No stalling while coasting issues for me. I can’t speak for the N/A group though.

MAGK944

I should think on an na you would want to keep all the momentum in the flywheel as possible, so heavier is better. Except maybe on a track car when your working the 4-6k rpm range most of the time and need the faster response. That seem about right?

thirdgenbird

ive got a fidanza flywheel teamed up with a sachs clutch.

in my experience the combination is good for aggressive/fun driving but maybe not ideal for a daily driver. ive not had any issues with it stalling but the rpms do drop quickly and if you are lazy it can throw you for a loop. ive had a few other experienced drivers drive my car and they didnt have any problems but i could see someone just learning how to use a manual struggling.

acorad

I have a lightened Fidanza and a kevlar clutch in my DD. I'll be swapping them both out soon for "normal."

Red1

Aluminum SPEC flywheel, cup disc and KEP stg 1 pressure plate. I wouldn't go back to stock if you paid me.

black944 turbo

choinga, I think you are having clutch issues (spec possibly?). What you are describing sounds look to aggressive of a clutch rather than the flywheel.


I have a buddy who put a fidonza in his car and they loved it. I personally will be doing this on my next clutch job.

ninefiveone

I'm running a fidanza fw and spec clutch.

Pros: the engine revs up (in neutral) a lot quicker which makes for slightly easier heel toe downshifts, etc. The faster response is a nice touch in those kinds of situations and adds to a feeling of a "free revving" motor. In gear I doubt it's making much difference to how fast the revs climb, esp since I'm running a 3.0 turbo.

Cons: you definitely need to pay more attention in town. Coming off a stop, etc. Its certainly drivable but as the traffic gets worse, the feeling of annoyance starts to creep in.

I'm neutral on it but my car is a long way from stock now.

choinga

no, it's fine. It's the setup - there's nothing wrong with the clutch. I make it out worse than it is - it's 'supposed' to drive like that. My point is - it sucks for DD... That's IMHO, of course...

pjburges

I turned my flywheel down in a lathe - made it to 9.6lbs. Sachs clutch. No issues.

The N/A has higher compression than the turbo - so low RPM stalling should be less of an issue.

You know....semi-truck drivers power shift every gear and never use the clutch in those big rigs except to get it moving....

Become one with the clutch Obi Wan.

acorad

I have no idea how semi-truck drivers shift, I always thought they double-clutched alot, but if you want to shift w/o the clutch I would think that a larger mass FW will help immensely.

On both upshifts and downshifts the longer time the heavier FW's greater momentum keeps it spinning at around the right rpm for the clutchless shift, the easier it will be to snick it into the next gear w/o the clutch.

While clutchless shifting is mostly something I've done for personal entertainment, the technique has come in handy a few times when something in the clutch system breaks and I'd have been stranded w/o it.

For me, around town, where I do most of my driving on my DD, the lightened FW becomes more of a pita than anything else. Granted, the chattering of the spec kevlar clutch sure doesn't help any either...

pjburges

I think a lot of the 'rough clutch' when it comes to people modifying them is that the springs are much higher pressure, and they get a crazy disk that tends to grab and chatter.

You're right though - the increased mass in the flywheel makes it much easier to do a clutchless shift and I should imagine it does keep a turbo spooled a little better.