Should I do a LW flywheel?

[Reason]

I don't really know If I want to or not. Last build I stayed stock and just had it resurfaced. I'm thinking If I do get one it will be a 14-15 pounder, talk me into getting one or not.

My car has a LW crank and alt pulley. The car is a daily driver, but also needs to be fun to drive. I'm leaning on going LW but want to here some personal experiences.

[Huffer]

If you do, swap the crank pulley back to the stock one. Drive it like that until you get used to the feel, and then swap the LW crank back on. Then you can see if it's going to cause any misfire issues.

I have a LW flywheel in my garage that I'm waiting to put on...but I threw out my stock crank pulley. Unsure if I want to keep modding because the paint job is getting chewed by rust.

[Reason]

Yea that was one thought...rust can be fixed. I neglected mine too, but I'm more concerned with having a car that runs with no mechanical issues then I'll worry about looks. I like my little rat, nobody looks twice at it when it isn't running lol.

[d1giPhux]

I'm running both a LW FLYWHEEL and LW Crank pulley on my 2.5 GT.

Things I've noticed:

-More vibration sounds from the transmission and or heat shields.
-Need to rev the car up more to slip into gear.
-Decrease in MPG

Been pretty reliable so far. Although, I keep wondering if its caused me some transmission damage. I'm not really sure. I get sketchy about these things. I get concerned because it DOES make a considerable amount of noise while downshifting sometimes. I think this may just be a heat-shield though. Feels smooth and solid however and runs great. I think that it may have decreased MPG too, as you have to rev it up more and it doesnt seem to have the same 'rotating mass' or w/e the heck its called.

[Perdue]

I'm in the same struggle right now. With the decrease in fuel economy and the idea that I want my legacy to be a daily driver, I'm leaning toward no. I have to drive in downtown traffic pretty often, so the hassle of dealing with it in traffic is turning me away too. I'm thinking about just getting mine resurfaced and maybe doing a lightened pulley instead.

If your drive is mostly highway and you aren't worried about a hit in fuel economy, I say go for it.

[Reason]

I'm actually going to get a new OEM one, this is always going to be my daily driver and I'm motor looking for high power numbers, same reason why I'm staying UEL vs a EL header.

[Wiscon_Mark]

Is there a reason that you guys have a decrease in fuel economy? It seems like decreased drivetrain mass should help economy as long as you didn't simultaneously get a lead foot...

[Garrison]

Is there a reason that you guys have a decrease in fuel economy? It seems like decreased drivetrain mass should help economy as long as you didn't simultaneously get a lead foot...
Due to less rotational mass you have to hold the throttle more to maintain speed.

[Perdue]

I think it works out hit and miss, mark. Along the lines of there is less mass to start moving, but not as much mass to keep moving, thereby less inertia. Great for acceleration but not so much for cruising...I think that makes sense. I'm no physicist though.

[Airgne]

I run lightweight everything as far as pullies and clutch. Love it. No lower gas mileage. Easier to rev match. Smoother engine.

[d1giPhux]

^ I'm not sure how the hell its possible you don't get worse MPG. Then again, I get terrible MPG to begin with. Like 20mpg or less. This could be due to the fact my foot is made of lead :lol:

The car does seem to be 'quicker off the line'.. however, it also decelerates faster as well and is harder to keep the mass of the car moving. If that makes any sense.

If i could do it again, id stick with OEM. I don't notice a huge difference, but it keeps making me wonder if I'm breaking stuff, or if my tranny is going to need a rebuild in the future. For now, everything is good though.

If you run the LW pulley, I don't think you will have any issues except for decreased MPG and possibly increased take off from the line and easier revs. Besides that, you don't really notice much. Only reason I got mine is because I got a super deal on a brand new flywheel kit. I'm also running a stage 1 clutch.

If i were you, id just stick with the LW pulley. I actually noticed more from the LW pulley then I did from the LW flywheel in terms of 'upgrades'.

Just my .00002 cents.

[anothernord]

I have an Exedy LW wheel, and it's great. You really don't have to rev it up any more than the stocker to get going. It revs with a ton more pep than the old stock one did.

As far as MPG: There's no way you could decrease your gas mileage by decreasing rotational mass on the driveline. Under cruise, when the engine is spinning at constant speed, the only mechanical losses are through friction. By definition, the only time the mass of the flywheel makes a difference is when the engine speed is changing. You can think of the flywheel as an inertia storage device. In simple terms, you're making it easier for the engine to increase in RPM, because there's less mass to spin up.

Remember, F=ma, (force=mass*acceleration). The less mass for a given acceleration, the less force required.

So if you're losing gas mileage, there's something else going.

[d1giPhux]

So if you're losing gas mileage, there's something else going.

Yeah.. i drive a subaru. :lol: thats whats going on! :P

[Wiscon_Mark]

Under 20mpg is kinda hard to achieve in my Legacy. You must really hammer it!

Anothernord - that's exactly what I was thinking. If it does lead to loss of mileage, I'm guessing it has more to do with how people change their driving style with a LW flywheel.

[Huffer]

It does take a little more skill to shift correctly with a LW flywheel - because the revs drop quicker you have a shorter expanse of time to get in gear.

Kind of like when people went from the videogame Outrun to Gran Turismo with it's pressure sensitive triggers.

[Reason]

Short throw shifter would match up nice with this then.

[Airgne]

After I put my lightweight flywheel and enkei rpf1s on I normally got 28-32mpg on the freeway. It only dropped when I put a outback drivetrain in.

[jey]

Is there a reason that you guys have a decrease in fuel economy? It seems like decreased drivetrain mass should help economy as long as you didn't simultaneously get a lead foot...
Due to less rotational mass you have to hold the throttle more to maintain speed.

Or you can just shift faster! :)

I love my LW flywheels - so much so that I hate driving most other cars now because the time it takes to rev up and down makes them seem sluggish.

[d1giPhux]

^yeah, i haven't driven a stock subaru in a while.. maybe i need to.. just so that I can know how much I'm not missing. :lol:

[rougeben83]

I agree with Jey. This shouldn't even be a discussion, if you can afford a lw flywheel, you should definitely get one.

[Garrison]

What weight is ideal for this? I live in the mountains and don't want to lose my ability to climb hills easily.

[growling_boxer]

I've been on the ACT streetlite (heaviest I could find at 14-15lbs) for 30k miles or so. It went in at the same time as a fresh Exedy organic clutch and group N engine and tranny mounts. driveline noise was so much louder afterwards, I don't know how much of the chatter and other noises are actually a result of the flywheel itself, since I assume the majority of NVH increase is the mounts.

I DD this car again now, and I love it. the stock flywheel was far too heavy to practically rev match, esp. across more than one gear. After putting this in, throttle blips give the needle a quick sweep back and forth through the RPMs to help you shift cleanly and quickly. if I am really taking it easy, I actually end up leaving my foot partially on throttle between shifts so the RPMs don't dip below idle before I can get it in the next gear.

as far as MPG, I'm pretty sure mine went down from the fun factor going up. However, I can get much better mileage when going through the hills calmly (small highway commute). in gear, off throttle and downhill, the car just accelerates until I get RPMs up closer to 4-5k (depends on the slope of the hill, obviously). uphill, I can more easily accelerate (and you have to, since you will lose speed faster).

[d1giPhux]

What weight is ideal for this? I live in the mountains and don't want to lose my ability to climb hills easily.

You won't lose any ability to climb hills.. at all. I can climb hills all day, and do. I'm running both LW flywheel and LW pulley.

Honestly, people keep making it sound like its a huge increase, or huge decrease in performance. Obviously they must not have a LW flywheel. Because its hardly noticeable in all reality. Sure, you can rev a BIT quicker, but its hardly that much different then driving a stock LGT. Its great by all means, just know what your getting into in terms of cost, and what exactly it will do for you. For the price to performance ratio, its pretty low. Its not going to turn your car into a WRX overnight by any means.

Growling_boxer pretty much sums it up really. Thats about WHAT you will feel. And yes, i think my MPG dropped as well because of the 'fun factor'.. or my 'lead foot factor'. :smt005

[susiemk]

I run lightweight everything as far as pullies and clutch. Love it. No lower gas mileage. Easier to rev match. Smoother engine.

+1
I have LW Crank pulley, Alt pulley, & an Exedy LWFW & it works well w/o CELs on my '03 Legacy L-SE Wagon.

My '00 Legacy Wagon CEL'd with just a LW crank pulley...

The crank/cam triggers are different '00 vs '03 - with the '03's not minding LW everything.

[Rhill206]

I've had the lightweight crank pulley on for about 2 years now and I love it, about 6 months ago I put the streetlight flywheel on and it shifts so much smoother, I noticed the heat shields making more noise too.. So I took them off. About 3 months ago, I had delta cams do a "torque" grind and then I started to throw the cel (so I pulled the bulb out of the gauge cluster), which they told me might happen without a tune. Now I just have to find a piggy back for the right price and put it in.

[Huffer]

Removing your CEL bulb is a braindead move. What if you throw a code for something else and you don't know it?

[Reason]

Pulling the bulb isn't a solution lol. I'm just sticking with my initial decision and keep a stock flywheel.

[Wiscon_Mark]

Removing your CEL bulb is a braindead move. What if you throw a code for something else and you don't know it?

This.

At least get a scanguage to read the codes if you don't want to see a CEL.

[kimokalihi]

What weight is ideal for this? I live in the mountains and don't want to lose my ability to climb hills easily.

You won't lose any ability to climb hills.. at all. I can climb hills all day, and do. I'm running both LW flywheel and LW pulley.

Honestly, people keep making it sound like its a huge increase, or huge decrease in performance. Obviously they must not have a LW flywheel. Because its hardly noticeable in all reality. Sure, you can rev a BIT quicker, but its hardly that much different then driving a stock LGT. Its great by all means, just know what your getting into in terms of cost, and what exactly it will do for you. For the price to performance ratio, its pretty low. Its not going to turn your car into a WRX overnight by any means.

Growling_boxer pretty much sums it up really. Thats about WHAT you will feel. And yes, i think my MPG dropped as well because of the 'fun factor'.. or my 'lead foot factor'. :smt005

It depends on how light you go. There's a very noticeable difference with my 9 lb clutchmasters WRX flywheel. The revs drop very fast when shifting which is a little annoying but I don't regret using it at all. Rev matching is excellent with this flywheel. I do not have lightweight pulleys though. I bought them and several people told me,"You better not run those with your lightweight flywheel or else!" So I sold them and I wish I had kept them. Stupid stock crank pulley started coming apart and wobbling really bad and shaking the whole car. When I took it off it had chewed the keyway up and I ended up buying another WRX pulley anyway (OEM).

[fullCircling]

i have the act streetlite and an exedy clutch, with the trans snout kit installed, and no issues here. the lighter flywheel definitely makes it more fun to drive. any lighter and it would prob be a bit of a pain in the ass on the street. its fun, and i still get decent gas mileage. and this is coming from someone that used to have an integra gsr with a lighter integra type r flywheel. weights on both flywheels are about the same, and they're both just as streetable. id buy it again, even for a daily driver.