Tips on whiteblock flywheel lightening?

[the poi]

I guess there's the first question to answer: should I bother lightening my 850 flywheel in the first place? I'll be using a 6puck Clutchnet clutch, on a 2X pressure plate, the car is pretty fat (I'd say 3800lbs now?), and I want it to be reasonable to drive ("reasonable" being a relative term, of course). That said, I'd really love to have this thing rev like a motorcycle, but who wouldn't.

Anyway, some analysis:

Stock flywheel (20 lbs even):



Cross section:





Easiest modification, cutting with a lathe. 16% lower moment of inertia (it's 17lbs):



Cross section:






And the most time consuming, and expensive, as I'd have to buy a rotating table for the Bridgeport at work. This one results in a 25% lower moment of inertia from stock (and its 15lbs):

(This is the friction side, this one includes the big lathe reduction from the previous version)


Cross section:




So ya. It's a 2 hour drive to the big lathe I have access to, is even the Phase 2 flywheel worth that kind of effort?

[Lord_Athlon]

The question is, are you going to be happy if you dont do everything in your power to make the pimp-mobile more pimp?

[Karl Buchka]

For your car and what you intend to use it for I would keep the flywheel completely stock. You don't have a race car, and lightening the flywheel will do nothing to help driveability.

But then again you only ever drive your car for about 10 minutes before tearing it down for some other ridiculous modification.

Also, damn you must be bored to draw up a copy of the flywheel in SolidWorks and do all kinds of math and **** on it.

[the poi]

Originally Posted by Karl Buchka

For your car and what you intend to use it for I would keep the flywheel completely stock. You don't have a race car, and lightening the flywheel will do nothing to help driveability.

I'm kinda leaning towards this, Justin likes his stocker, and his hooptie doesn't weigh as much as a bus like mine does

But then again you only ever drive your car for about 10 minutes before tearing it down for some other ridiculous modification.

I can't help that I have an insatiable lust for modzzzz

Also, damn you must be bored to draw up a copy of the flywheel in SolidWorks and do all kinds of math and **** on it.

[kildea]

yeah you'll like it as it is i bet ... it's got such a monster crank anyways, it'll not likely rev like a z car or anything once lightened, even if you drop the 25%

seriously that 6 speed is going to be the balls ... moar movies please!

[Gabe244]

I'd be afraid of the slim slim slim chance of it fragging. Some scary pics have been posted in one of JV's threads.....

[Johann]

This is wat I did,

Stock,



Modded,



Weight went from 9.4 kgs to 8 kgs (~17.6 lbs)

The difference in drivability is slightly noticeable, engine feels a bit more snappy.

Personally I would reconsider the 6 puck when going for drivability. Might become harsh engaging overtime.

[volvorsport]

http://homepage.ntlworld.com/mj.slater2/101_0121.JPG

$300 .

[Captain Bondo]

I didn't see any need- I did find it strange that you're looking at using a 707 pressure plate and some sort of T56 spline'd disc though.

Having the flywheel drilled for a 7.25" twin or triple plate clutch would reduce inertia, increase torque holding, and be easy to get with a T56 spline, and they're meant specifically for the hydraulic throwout bearing on the tranny.

When I do mod mine it will be for that sort of path, with a 600-800hp capable setup in mind.

[the poi]

Gah, I was all content and then both you guys come in here and ruin my morning . I think I'll lean away from the off the mother****ing chain aluminum flywheel (I completely forgot you had those, gah!), because I want some sort of driveabilty.

That said, Kenny, I do intend to drive this thing regularly (it certainly ain't no weekend racecar), will the 7.25 twin be too light when combined with a stock flywheel? And SPEC at least, makes a 800ftlb rated twin disc organic for the Camarobird. That is exactly what I want. Everyone just sells them in packages, so I'll have to see if I can get them to sell me just the pressure plate back (and hopefully there isn't anything special with their flywheel). All of these clutches though have unsprung hubs obviously, is that going to suck? I will most likely go this route if it's going to be a) driveable and b)short enoguh to fit in the aw3040 bellhousing.

edit:// Fidanza's is 8 3/4, same 800ftlb rating. SPECs and Fidanza are using strapped floaters, and apparently larger size than the conventional 7.25. It's the right market though, driveable and strong...

edit2:// currently getting semi re: fidanza and spec twin discs. Seems absolutely perfect when combined with a stock flywheel...

edit3:// and exedy sells a sprung hub/strapped floater/800ftlb! 8.5" making it effectively just a way to avoid using the 6 puck...

[kildea]

honestly, a good light/strong approach might be a button flywheel w/ clutch, attached to your flxplate ... i know i already mentioned it, but for the next guy maybe

... or you could always kick it like this bad larry ...





... no i just read your post above ... that sounds like the way to go, just sucks you'd need the presure plate face off of the 'maro plate ... are you sure you'd need it? my 850 pressure plate and 6puch rx7 clutch disc work well together, no problems yet ...
maybe i'm misunderstanding your plan though.

[the poi]

Originally Posted by kildea

... no i just read your post above ... that sounds like the way to go, just sucks you'd need the presure plate face off of the 'maro plate ... are you sure you'd need it? my 850 pressure plate and 6puch rx7 clutch disc work well together, no problems yet ...
maybe i'm misunderstanding your plan though.

Most likey, I should be able to just bolt the twin-disc system to my flywheel just fine. It's just that most of these are sold with a flywheel, so as long as there isn't any weird interface, I will be fine. It's just that I want to find a distributor that will split the package, cause I have no use for the 400$ flywheel.

edit:// and who is that bad larry pictured above? If I do go with one of these El es Juan twin-disc setups, it's not going to be all that much lighter. And since it means I can get easy-to-modulate organics material, I could probably go with a lighter flywheel then. An aluminum flywheel might just be ticket then.

[Captain Bondo]

Lots of kits afound without flywheels- check the John V thread about bllet redblock wheels, I posted some links there.

The other thought is that with the Hx35, you will top out between 400hp and maybe 450hp as a maxiumim anyways, so maybe you want to just try the 707 PP and a standard disc to start with anyways, since that will hold as much power as the current turbo setup is capable of- unless and upgrade is on the horizon on that front as well. Just depends on the long term plan I guess.

[kildea]

Originally Posted by the poi

edit:// and who is that bad larry pictured above?

google image search for: mettler nissan

[the poi]

I may have figured out why some stuff comes with it's own flywheel. The contact surface ID may be smaller than the stock flywheel. Hopefully I can find this out from the manufs next week. All the 7.25 stuff I'm finding is all very thin unstrapped floaters and cerametallic clutches. SPEC's LS1 thing seems to be the best bet, as they're really good about custom crap, it's close to the 850 clutch diameter (so it may fit on the 850 flywheel), and it's a strapped floater with organic discs--designed for precisely what I'm using it for.

That said, if it's too small for my flywheel, I'll bite the bullet and make a "mini flywheel" and bolt it through my flexplate, sandwich style (and then I can keep my T6 starter!). Just to keep me occupied, would I be best with iron or steel?

[volvorod85]

For your amount of torque a 2 disc setup may not be a bad idea...as far as lightening, i wouldnt...youve got 6 cyl, thats a help first, you should have no problem revving that thing to launch as a stock flywheel...youve got a T56 with a low first and a 4 soemthing rear end....when id worry about is the clutch slippign before the flywheel having to be lighter
Mark

[Kuikka]

For anything producing power I would not go with stock flywheel, specially lightened one. But as John V said about 7.25" 3 disk trasferred to 2 disc with organic discs I'd bet my money on it. I liked mine that was built like that.. Now that you draw so much with CAD anyways just make an steel flywheel to combine, you can't install new legs if something goes wrong with lightened flywheel anyway...