'Machined Stock' vs 'Store Bought/Billet' Lightened Flywheel

[juicersr]

Want to use a lightened flywheel in the process of my rebuild, and was wondering if anyone could tell what what benefit, if any, there is to spending several hundred bucks on a lightweight flywheel (Patrick Motorsport, Fidanza, etc) vs just having my stock 3.0 flywheel machined. It is a (mostly) street car which will see some track time. Is a machined stock flywheel weaker? Thanks

[1980 911 sc]

A light wt. flywheel is FUN, it revs up / down so much faster it feels like a race car.... I cant really explain it any other way, when most people shift they just time it, i have to blip, i cant help myself.

now as for machining it yourself.... i dunno, I don't think the would be heat treated or anything, but you better make sure you have no runout and that you can really balance it... if you don't know what I am saying, I would not do it.

my lame 2c.

[juicersr]

I'm already sold on the lightweight part.

I am not machining myself. EBS, the same guys who are doing all of the machine work on my engine parts, will be the ones to machine the flywheel to 'lightweight' if i wish . Just wondered why anyone would spend 300-400 bucks on a 'lightweight' flywheel when u can get one machined for about 100 or so. That's all.

[BURN-BROS]

Originally Posted by juicersr

I'm already sold on the lightweight part.

I am not machining myself. EBS, the same guys who are doing all of the machine work on my engine parts, will be the ones to machine the flywheel to 'lightweight' if i wish . Just wondered why anyone would spend 300-400 bucks on a 'lightweight' flywheel when u can get one machined for about 100 or so. That's all.

Can you verify the amount for me? It seems pretty low for the work involved.

[juicersr]

Aaron, the $100 figure was based on Competition engineerings website. Don at EBS quoted 'about 200' depending on how much the flywheel would be lightened. Even he, however, couldn't clearly tell me if there was any benefit to buying an aftermarket flywheel vs lightening your own. Still confused. Anyone on the board had issues with a machined lightened flywheel? I have seen a post about light flywheel failure, but those were aftermarket.

[RWebb]

there are numerous but scattered posts on various issues...

lightened flywheel overall - may mess up DME or just on BMWs
- hard to start from stop

Fidanza bonded types alloy smears; comes unbonded

Cutaway types - rip thru clutch real fast

-- above off top of my head -- you7need to uy some effort into searching/reading to get all the comments

[Formerly Steve Wilkinson]

I think the stuff about lightened flywheels being hard to start from a stop is an urban legend. I have a Truman in my well-modified SC, and I stall our stock Boxster far more frequently.

[BURN-BROS]

Originally Posted by juicersr

Aaron, the $100 figure was based on Competition engineerings website. Don at EBS quoted 'about 200' depending on how much the flywheel would be lightened. Even he, however, couldn't clearly tell me if there was any benefit to buying an aftermarket flywheel vs lightening your own. Still confused. Anyone on the board had issues with a machined lightened flywheel? I have seen a post about light flywheel failure, but those were aftermarket.

Thanks, I have lightened a few and priced them around $200.00 beacause of the time involved and I have never checked what others have charged. One customer prefers a lightened stock one because he likes the material/performance it provides.

[juicersr]

Thanks for the input guys. Think i will just have mine lightened by EBS, as Don there said they could 'customize' it so that it is lighter, yet would allow better street drivability than one of the 'RSR' types. That being said, i may have found the answer to my own question.

[Mahler9th]

I know John and Don at EBS and they are great. Many of my engine parts come from them. I have a race car (3.8 liters, about 360 bhp, and 2000 pounds), and I have not been able to justify the Fidanza. Someday if/when I do, it will really be all about dead weight, not rotating weight, and even then it won't be that much compared to a cut stock flywheel. I don't think EBS cuts them down in house... if not I am sure that they use extremely experienced machinists.

For an application as described, I's spend the money on something else, and ask EBS to cut down the stock unit and head on down the road.