General Jack

iTrader: (4)

So correct me if I'm wrong, but the stock LS1 flywheel weights about 24 lbs, and the lightest aluminum flywheels are 12.5 lbs, with billet steel coming in around 18 and chrome moly around 15.

Obviously, there is a huge difference between stock and aluminum, relating to quick revs and launching at the track, since aluminum weighs only half or so of stock

But how noticeable is the difference between the billet and the chrome moly, assuming its about 3 lbs (18 versus 15, respectively). Will the 3 pounds make a noticeable difference in the quick revs and/or launching? I'm talking seat of the pants. And will the 18 lb billet steel rev noticeable quicker than stock?

Nightrydass

take a 7lbs dumb bell in your hand and rotate your wrist; take a 10lbs dumb bell and do the same thing.

you tell me

Aetos

iTrader: (4)

I tried, but I'm too weak to pick up a 7lb dumb bell




If what I've read is correct, 10lbs of rotational mass(ie: most things on the drivetrain) is equal to 100lbs of static weight. Meaning, if we take the theory that 100lbs is equal to .1 seconds on the quarter then every loss of 10lb rotational mass should theoretically gain you .1 seconds at the strip.

68birdls1

iTrader: (46)

is this right?

Black02SLPSS

iTrader: (5)

Yeah that sounds right to me

teke184

iTrader: (5)

i went from stock to the fidanza flywheel.

while i could tell a difference it was NOT a night and day difference. it did rev faster but as far as feeling it SOTP in a race situation, i just barely could tell.

so the difference from a 3lb change probably would NOT be noticable.


although there are guys who say they can fell the power difference from doing a throttle body bypass.....3hp

BarneyMobile

iTrader: (4)

Agreed, I have the Fidanza 12.5lb fw and what I notice the most was the motor rev'd quicker but seat of the pants was almost unnoticed. It will show a difference on the dyno though.

teke184

iTrader: (5)

i'm hoping i get an idea of gains from the light flywheel when i get dynotuned next month.

granted there are other mods...but i think my torque will jump more from the flywheel than it would with the other mods.

seems i remember the dyno comparison of the alum driveshaft resulting in more torque but nearly 0 hp gain.

General Jack

iTrader: (4)

Thanks, this is kind of what I was looking for... So it sounds like:

• probably not a discernable difference between the 18 lb and 15 lb
• maybe some difference between the stock and 18 lb
• probably a noticeable difference between the stock and 15 lb

ghettocruiser

iTrader: (17)

My donor car/motor/trans was set up with a spec 3 and aluminum fly wheel. Im now running an LS7 which has a HEAVY flywheel compared to the alum. I noticed a pretty big difference in motor response. The alum. flywheel set up was a lot quicker to snap to redline...like if the tires lost traction. They'd spin up fast as lightening. While my car still revs great, there is a definate difference.

As far as the SOTP for power...I didnt notice anything substancial. Nothing worth noting.

As far as SOTP for drivability...BIG difference. The alum. flywheel made driving in traffic alittle touch and go. Launching required more revs than with the heavier wheel. There was no way to just ease the clutch out and start moving with the alum. I mean..you could, but it was a pain. Now, I can pretty much start off from a light with no gas.

I liked the alum...but ILl never go back. If anything, Ill find a middle ground somewhere because the LS7 set up is definetly a boat anchor. Heavy as heck.

J.

teke184

iTrader: (5)

agree with the above

stock i could just let the clutch out easy, and it would pull out from a stop. but the alum fw just stalls out. some of this could also be due to having a race oriented clutch disk (stg 4 with no sprung center hub).

you most def have to give more revs to pull out

and i also agree with how fast the car runs to redline once the tires break free. i guess without really thinking about it much i assumed it was due to the power i was making. but the faster reving of the light FW makes sense too.

down shifts are nice, if you like to throw it through the curves. a light tap of the throttle to rev match and release the clutch. not as much of a jolt when dropping gears at above normal speeds/rpms.
i notice it alot more when i drop 4th to 3rd to pass someone...i generally don't rev match then since i'm in a hurry...it just snaps to speed and i'm pinned to the seat. ....with the TDs wailing!!!



if you are really in tune with how your car feels under WOT, or in a drag race situation, you probably will notice a considerable difference going from stock to any light flywheel setup. say if you hit the track weekly, but i've never had my car at the track in almost 6 yrs. and all i do around town is slow starts...and fast shifts for 1 or 2 gears.

SuperSport01

I used a billet steel flywheel in my SS due to having issues with the fidanza aluminum one in my boosted honda.

ghettocruiser

iTrader: (17)

teke184 good call on the downshifting. I forgot to mention blipping the throttle was effortless. Just a tap would send the RPMs where they needed to be.

I might be crazy here...but I felt that my trans was alittle smoother with the light set up. Could just be the perception from the snappier revs...or my hydraulic issues etc etc. Just something I noticed when I did my second build and installed the LS7 clutch.

teke184

iTrader: (5)

something to add...

i did notice a slight increase in high frequency vibration after my clutch/flywheel install.

not sure it was the fw's fault...but with less mass to soak up vibration...its possible.

then again i've got poly motor, trans, and torque arm mounts

fortmyerspolice

iTrader: (7)

Did you get it balanced?

Viper

iTrader: (6)

Good question:
"Did you get it balanced?"

I had mine balanced and it was off quite a bit. I have poly motor, trans, and torque arm mounts too and it's very steady now, and the trans feels smoother. I'm running a Fidanza aluminum and SOTP was not noticeable but revs are lightning fast now; you have to be on your game to nail a shift at redline in 1+2.

MeentSS02

iTrader: (11)

I went from a 58 lb Ram Powergrip/Ram billet steel flywheel setup (as weighed by me - full assembly) to a 37 lb RPS setup, and I noticed a BIG difference. It was harder to take off from a stop (just had to relearn how to drive it), and it was noticeably quicker just cruising around when giving it some gas just to putt around.

Dropping 3 lbs? Probably wouldn't notice that as much.

teke184

iTrader: (5)

didn't balance it, but contacted fidanza and they said it was balanced.

that doesn't mean it couldn't have been balanced better....but oh well.

when i pull it out again...i'll have it redone...by that time it will be time for a new friction plate...