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lightweight flywheel?

5.9K views 35 replies 24 participants last post by  ggaveit2u  
#1 ·
is there a big gain with the flywheel or should i keep my 300 for some thing else
 
#3 ·
I would highly recommend not buying a crappy e-bay flywheel. I'd buy it from a reputable company. I ran a 9lb 2 piece flywheel and loved it. I would never suggest buying one to make you faster if you don't actually need a clutch and flywheel. Just wait till you actually need to replace it.
 
#6 ·
+1 for brand name

Some cheap flywheels have been known to 'explode' due to the different expansion characteristics of the types of metal used to make them. (aluminum core w/steel teeth, for instance) Other cheapies are actually just lightened versions of the stock piece, which are structurally weakened by drilling/milling/etc.

I've got the ACT flywheel and an exedy clutch, same package that a vendor is offering on special right now for $600 shipped.

IMHO, if you're going to do the flywheel, do the clutch as well, since the install is a major ordeal. I don't have the technical know-how/time/tools/garage to do mine myself, labor ended up costing more than the parts. :noes:


And yes, they're awesome. Drivability is like whoa compared to how it used to be.
 
#8 ·
TheMues said:
that sounds cheap. the clutch and flywheel i was looking at was 1000$ but i could do the labor myself so that would be the total. whered you get your ACT flywheel and exedy clutch?
They aren't as expensive as they used to be. Take that 400 bucks and but something else too.
 
#9 ·
worth it? Yeah!!! but i think i say that about every mod...except the pinstripe grill... that was worthless :)

I didnt put in the lw flywheel until I was already replacing the clutch. but it does make a nice difference.
 
#10 ·
Get the ACT off of ebay. Its only $254 shipped

Wouldnt recommend the Fidenza. My brother has one and runs it to 7.5k in his sentra. It said in the directions to get it balanced before you put it in. We didnt and havent had problems. My ACT and Exedy didnt say anything like that though.


Very much worth the money. I have one in both my impreza and DD legacy wagon.
 
#12 ·
I'm not a drag racer but I have read on other sites that the only people consistently disappointed with lw flywheels are drag racers because the decreased rotational intertia makes it harder to launch.
 
#13 ·
Lachlan said:
I'm not a drag racer but I have read on other sites that the only people consistently disappointed with lw flywheels are drag racers because the decreased rotational intertia makes it harder to launch.
I've heard the same. Makes sense. From what I gather, the main benefit of a lightweight flywheel is ease of rev-matching and reduced wear in the gearbox, along with a marginal gain in acceleration due to reduced drivetrain mass. The downside is the difficult launch.
 
#14 ·
Lachlan said:
I'm not a drag racer but I have read on other sites that the only people consistently disappointed with lw flywheels are drag racers because the decreased rotational intertia makes it harder to launch.
You sir are correct. When ever you hear someone mention that stock flywheels are better it's almost a fact that they are drag racers...for the most part.

I went to the drags once with my lightweight flywheel and had no problem launching. Did it the same way that I did it with my stock stuff.
 
#17 ·
I've got the stage 1 exedy clutch and their lightweight flywheel. Got the kit from z1 auto. Great place Adam is very informative to talk to. I had it installed 4K miles ago. I LOVE IT. BEST MOD I've done by far. If you need a clutch and have the extra money to spend I highly suggest the lw flywheel. I haven't had any problems with check engine lights and the car is still very driveable, but lots more fun. Exedy flywheel is 14.something pounds compared to the 25 pounds on the factory. Great revs. just have to get used to applying a little more gas on the start.
 
#18 ·
SGMongoose said:
would it be worthwhile to change the flywheel without changing the clutch? my car revs raise and drop too slow, but my act clutch is still good.
The question is would you be doing this buy yourself in your garage or would you be taking it to someone? Honestly if I didn't need a clutch I would just wait till I needed a new one. I even do my clutches and don't have to pay for labor and I wouldn't put a flywheel just to get faster revs unless the clutch was needed.
 
#19 ·
carolinaguy99 said:
you will throw CEL's with a lightweight flywheel........ misfire codes to be exact, at least in 98's you will..........
Yeah, generally anything less then a 12lb flywheel will throw codes. Honestly mine only got thrown maybe 3 times under certain situations in a year and a half or so.
 
#26 ·
scoobaroo said:
does the lw fly take away any torque? i got a friend who says that lw flywheels reduce torque but i'm pretty sure he's wrong. and OEM flys are 25LBS?!?!??!?!? i'm so getting one soon.
Your friend is clearly not a physicist ;)

a lw flywheel will do absolutely nothing to your torque curve. Your engine is making a certain torque and will make that torque nomatter what flywheel, transmission, prop shaft, diffs, wheels, tires, etc. you have.

It will increase your acceleration though. Torque is equivalent to a rotational intertia times an angular acceleration. If you reduce the rotational inertia (lighter flywheel) your torque doesn't change so your rotational acceleration goes up. Where the tires meet the ground rotational acceleration becomes linear acceleration.

FWIW my stock flywheel was about 23 lbs and my gruppe-s flywheel is about 13 lbs. I also have a lw accessory pulley and I'm not throwing any codes.

I believe the code you throw is because the engine thinks it's getting a misfire for some reason.