There has been some discussion on the 5th gen board regarding whether a lightened flywheel helps or hurts 1/4 mile performance.

Apparently, stored energy in the flywheel actually helps in drag racing and lightening the flywheel reduces that stored energy and hurts 1/4 mile performance.

The real question is do you gain enough power from the flywheel to offset that loss.

Anyone dyno or have any experiences with the lightened flywheel. I have to replace my clutch and am trying to decide whether to go with the lighter flywheel. But I don't want to lose et at the track.

 

Strange I've never heard that theory...

The only thing I can think of that is negative with a lightened flywheel is the rpm's dropping too fast in between shifts.

I was under the full impression though that the 'freed up hp' would compensate though.

...discuss...

 

It makes getting a good time that much harder. Because of the energy storage losses. So if you can drive well, it should improve your times(in theory). But if you aren't as good as a driver(bog launch, wait too long inbetween shifts) you may increase your 1/4 times.

But then again, I don't 1/4. The increase in revability for everydriving is priceless.

 

My thoughts are posted in the 5th gen fourm thread.

 

jeff92se is right, that stored energy is called momentum, and if you have a lighter flywheel, you have none of that, therefore the rpms fall that much quicker (not to mention rising quicker as well). But another bad thing i've heard, from my manual trans ase prep class, is that a lightened flywheel makes everyday driving unbearable because of the hard shifting. Is that true, also, would that hold up for an automatic as well?

 

Ah well you are right in a odd sort of way. The stored energy might better be described as kenetic energy( I could be wrong)


Actually is is very false. A lightened unit "might" make everyday driving more difficult. But it depends greatly on how much lighter the unit is.
Um.. auto trannies don't have flywheels per say. They have a sheet metal plate with a ring gear for the starter. Torque convertor is what takes the place of a flywheel in an auto.

I guess it's early in the semester

 

I have a lightened flywheel...I got the 5 lb flywheel from stillen. It actually uses the stock ring gear...just replaces the wheel attached to it...I remember lifting the two while I was comparing and it is a big difference. Supposedly I gained about 6whp with it. It definitely does raise the revs very quickly but about the revs falling...it's not an issue...even if you aren't that quick on shifting...it won't hurt you unless you purposely wait to shift.

 

I just got the Stillen flywheel installed myself and I'm very happy with it. I don't think it effects driveability at all... in fact I think it makes it easier to drive. The car revs up and down much faster, and while it takes a little getting used to, I find it easier to shift and much easier to rev-match when downshifting. I can't really tear into it yet because I'm breaking in a new clutch, but I can feel it's quicker down low. Overall the car feels much more responsive.

 

I think buying a mustang would help 1/4 performance ..

 

Bingo

The Fidanza flywheel is probably the best compromise for street driving because they don't shave a huge amount of weight off the plate. The Stillen flywheel is pushing it, IMO. It is possible to be quicker in the 1/4 mile with a Fidanza/Stillen flywheel, but it requires you to be VERY good at throttle/clutch modulation off the line. The lack inertia could possibly slow you down because the first 100' of a 1/4 mile race is the most important. If you bog, you're done. I even noticed a harder time launching with the my UDP. It's far easier now to hang the rpms at 4000rpms on a launch without the UDP. Wiith the UDP, I was required to rev the throttle up and down to hang the rpms. I did some calculations for the Fidanza unit and you're looking at ~.04-.05 seconds in the 1/4 mile.

Lightened flywheels are far more ideal for true track racing like auto-X and such.


Dave

 

non sequitur

 

Tell that to all these guys on here with a max that are smoking Mustangs in 1/4 mile.

 

Leave...

 

Ha, true that you can go faster for cheaper with a stang, but it's kind of bad judgement to say that here. It'd be like going to a Geo forum and telling them your max is faster than they are. They're going to tell you they have modded storms or something that'll smoke a maxima, and they'd be right, comparing the fastest of their cars vs the slowest of another. Not much respect, so keep it quiet.

 

what we need is about 5-6 maxima peeps that actually have the lightened flywheel and run the track regularly.

I30tMikeD is about the only person I know of that fits into this category. dig up his post !

i also would like to do this mod, since im doing the clutch and tranny in a month or so, but at present i dont feel confident about this one.

 

Im no help because Ive never run the 1/4 with the stock flywheel. But I am one of those with the 5lb one and I think its money well spent though it did make the gas pedal more sensitive!
In time, I doubt its something that can't be made to work as well or maybe better than stock at the 1/4, IMO. Just a tougher task to learn the fine art of the launch.
Im rally looking forward to the next journey to the 1/4 track (my 2nd). Was going to go tomorrow but it was cancelled

 

keep me updated ..

 

did you say buy a stang?

http://twotone.ghostspace.com/limaxi...ang%20Kill.avi (sorry 56k)

 

buying a mustang is the worst thing you could ever do. Junkstangs are the biggest waste of machinery ever invented

 

Yeah right.

I've driven lots of Stangs, modified lots of Stangs, and I've watched Stangs own cars on the track and auto-X. They're not unreliable either. If I were to keep my Maxima, I'd be looking at a 90-93 LX 5.0 notchback. Talk about fun and fast cars. I've owned plenty of Stangs at the track, but for every 5.0/4.6 I beat, I get owned by 3 of them.


Dave

 

This is how I'm thinking about it. You supply the energy that is stored in the flywheel during acceleration and benefit from the stored energy when you let of the gas. The time you spend with your foot on the gas during a 1/4 mile race is definitely more than the time off. Therefore you are supplying energy for a longer period than you are recieving. If you can reduce the amount of energy(by using the lighten flywheel) that you have to supply then you should expect to see gains. Another factor to consider is that your rpms rise faster so your shift points would be earlier.

 

that was a huge waste of a download, i was expecting something alot better at 96mb! yikes

anyways as far as the flywheel issue, i dont think its possible to know just what we can get from it. what it all comes down to is comfort/driver/driving style. for some it may help, for some it may hurt.

 

I need Advice, My current Mods are
Intake
Y-pipe
B-pipe
ECU (next week)
I have to replace my clutch in the near future so i was thinking about getting a flywheel. There is currently a GD goin on $334 for Fidanza. If i decided to get this Flywheel would i notice the same increase like the Y-pipe and ECU. what the ~horsepower gains?

THANKS
Mo

 

Buy it, you'll like it.

 

I must say I agree with all you said.
I don't really like them as much as my Maxima, but I would own a 5.0 in a heartbeat. They are a blast to drive, and easy to fix up.
They are not crap, well at least not some of them.

 

Thanks JeffesonM, I need more opinion on wheather or not i should get a flywheel.

 

Bump it up to the top

 

i just installed the unorthodox flywheel, an ACT 4 puck clutch and UDP's (I installed the clutch and FW a week before i put the pulleys in to see th difference). Without the pulleys i can chirp third gear. I could barely, just barely get second before. Now, if i drop down to second at like 40mph, i can boil the tires. Just so there is no arguing about what kind of tires i have and how worn, I have yokohama AV520 225/45/ZR17 with about 4k on them. As for 1/4 mile times, the flywheel and clutch are probably the best mods ive done to my car (.3-.5 off the 1/4). And for a daily driver, the clutch/FW/UDP mods are nothing that a little getting use to can't cure. I have about 1k on my new setup and it's like driving a brand new car. I love it. I say go for it...it's well worth it!

 

Hi guys I have a Fidanza flywheel and I drive it every day honesly for the
money is not worth it but I guess if you want extra ponnies investen on a
N.O.S kit not on a flywheel .....

 

Wow, I'd always written off lightened flywheels as reducing drivability, but now that I actually have a Maxima I've found that passive rev-matching can be a pain. I especially find it hard to do a fast 1-2 shift without jerking into 2nd too much. It may just take more getting used to the clutch sweet spot, but now I'm thinking a light flywheel would be a good mod.

I have one concern: on my car (as seems to be the case with most MT cars), when you let off the gas while cruising in gear, there's a little jerk when you let off. When you depress the pedal again, there's that jerk again. (This point would logically be where the engine stops pulling the car and the car starts pulling the engine.) Would a lightened flywheel make this more pronounced? If so, I don't want one because the little jerks p!ss me off enough already. With skill you can minimize them but never eliminate them, unless someone here knows how to (or what's wrong with my car...).

 

Hey thanks for your advice. How would you compare the Flywheel to y-pipe, or is it comparing apples and oranges.

 

You can't compare the two. A y-pipe will help acceleration in every gear. The lightened flywheel will be VERY noticible in 1st gear, noticible in 2nd, barely noticible in 3rd and so on. It only makes a difference in gears where the engine has a chance to wind out quickly.

 

I wouldn't suppose you have any timeslips or dynos available to show us how your gained over 30-40whp to drop .3-.5 in the 1/4 mile with a clutch, pulley, and flywheel?

The reason you're ripping the tires is because of the clutch. It grabs incredibly hard therefore the load is transferred to the weakest link, your tires. You're walking on egg shells though because that puck clutch is going to spell the end of your tranny very soon. I'm guessing 3rd will be the gear you shred.


Dave

 

Nobody knows?

 

Yes, I've also ran a few GT's on the track and layed the smackdown on a few, but a lot of that was driver. Mustangs aren't near the best of vehicles, but they're definitely not junk. It's the cheapest way to go if all you ever cared to do was step on a gas pedal in a straight-line for a few seconds. Believe it or not, the maxima is capable of a lot more than just pedal mashing, but if your sole purpose is to go fast in a straight line only, why not get the cheapest alternative? However, it is pretty darn fun to surprise a few pony owners how your stock frontwheel drive 4-door kept up with the v8's.

 

Okay, you speak of this "stored" energy. Did anyone ask where that energy came from?
That angular momentum must be created somehow.the "horsepower" is freed up by eliminating the excessive power necessary to develop extra angular momentum in a heavy flywheel. that is what makes the lightened flywheel a performance mod. In retrospect, It's this angular momentum that keeps the flywheel spinning between shifts. So, its a matter of driving. if the driver can keep the rpms in a close to perfect range with the lightened flywheel, it is obviously faster. A slower shift that doesnt utilize the stored energy will cauwe a lightend flywheel to slow down a 1/4 mile time significantly. So in lehmans terms: bEyatch, you get that thur thingy, you better know how to drive!

 

to your post jlsund. But to add to what you already said, probably the trickiest thing is going to be relearning how to modulate the gas/clutch to prevent the engine from bogging at launch.

 

the "jerk" you speak of is your motor moving around in the engine bay, cant stop that, but it can be reduced by some stiffer motor mounts such as the PR mounts

 

Hm, I didn't think of that. I'll have to consider stiffer mounts. I'm just worried about excessive vibration at idle.

 

That "jerk" you feel can also be attributed to the space in between the gears themselves.