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No one does make one trust me i have checked. But yes a good machine shop can lighten your stock one. Thats what i had done to mine. He took about 3 1/2 lbs off my stock one. And you can feel the difference.
 

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I thought I heard that the 1.9 HO could use the 2.3 flywheel, there are a few aftermarket flywheels for the 2.3.
I had about 3-4 lbs taken off mine too. It does make a noticable quick crisp throttle difference.
When done right, it's safe.
 

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Not true tito,

The lighter the mass of the flywheel, the lower the mass moment of inertia and the less horsepower it takes to turn it. Essentially the car will rev faster and get a small power gain. Of course the more material you remove from your flywheel, the less smooth the engine will run to an extent. This is one of the two main ideas behind the underdrive pulley as well since they're about 3lbs lighter than the stock pulley.

Matt 8)
 

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fixitmattman said:
Not true tito,

The lighter the mass of the flywheel, the lower the mass moment of inertia and the less horsepower it takes to turn it. Essentially the car will rev faster and get a small power gain. Of course the more material you remove from your flywheel, the less smooth the engine will run to an extent. This is one of the two main ideas behind the underdrive pulley as well since they're about 3lbs lighter than the stock pulley.

Matt 8)
You were right the first time. It'll take less hp to turn the flywheel, which will allow it to rev faster, but you will not get any sort of "power gain." The engine will not produce more hp because the flywheel is lighter.

Now that that is clarified...try having it shaved next time you replace the clutch, it may need resurfaced anyway.
 

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James92Scort said:
you will not get any sort of "power gain." The engine will not produce more hp because the flywheel is lighter.
I can see where your coming from on this James, and esentially you are right in a respect. The engine will not produce any more power than it already does. What you are doing is freeing up power lost due to having to accelerate a larger mass. Everything that moves takes energy to get it moving. If my flywheel is lighter and takes 2 less hp to accelerate and get moving than stock, that is two more horsepower available to me for output.

Matt 8)
 

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So essentially, if I had 88hp with a parasitic power loss like a heavy flywheel, and free up 2hp from lightening it, my output is now 90hp.

Forgot to add that :wink:

Matt 8)
 

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fixitmattman said:
So essentially, if I had 88hp with a parasitic power loss like a heavy flywheel, and free up 2hp from lightening it, my output is now 90hp.

Forgot to add that :wink:

Matt 8)
No. You're not getting what I'm saying I guess...you will NOT make more power by lightening something up. If you make 88 flywheel horsepower and you lighten up your flywheel and make 90 hp, you were already making 90-92 hp.

Now if your car says that 88 ponies are rotating at the flywheel, then you do a chassis dyno and you make, say 77 hp at the wheels and then lighten up your flywheel and make 78, it's because that x amount of weight you took off was using up the kinetic energy equal to that of 1 hp (really this is a figure of torque, the real twisting force turning your wheels) to spin it and not the wheels.
 

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The only thing he'll NOTICE is that his car revs faster while it's in neutral.

He will be making a few more horsepower, but he'll obviously never be able to tell the difference...

Lightening the rotating mass does increase HP, but 5-10 lbs. isn't going to make too much of a difference.

From Corksport.com -

UNORTHODOX RACING Underdrive Crank Pulley (91-92)
CNC-machined from lightweight 6061-T6 aluminum billet. Average of 8-15hp/6-10lbs-tq on NA engines, higher gains on modifed engines. Two ways of gain. There is an average of 2.7 HP gained from every pound lost off the crank shaft. With the lighter accessory pulleys, as much as 15% to 30% more power can be found. 85% of gains are from weight loss. Rest of the gains are from underdriving, which accounts for about 15% of the total gains. A small amount of underdrive is used to keep the charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. *not actual part shown*
 

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Yes, that means you'll see the horsepower YOU ALREADY HAVE returning from the hidden recesses that is parasitic loss to help turn the wheels, but you will NOT make more hp from the motor by lightening the flywheel/pullies.

If you want a pretty cheap way to actually help the motor make more power, help it breathe easier, intake, PnP the TB and IM, header, exhaust and you'll actually see horsepower gains on the dyno.
 

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TitoElSpicco said:
The only thing he'll NOTICE is that his car revs faster while it's in neutral.

He will be making a few more horsepower, but he'll obviously never be able to tell the difference...

Lightening the rotating mass does increase HP, but 5-10 lbs. isn't going to make too much of a difference.
:?

Have you had a light weight flywheel?
I do. There is a huge noticeable difference and not just in neutral while reving. Any body that drives my car can tell there is somthing different about it. Any time your in first gear with the clutch all the way out you can blip the throttle and instantly the wheels break loose, they are not skinny crappy stock tires either, there a nice set of 205/55 15's. This is with my 96lx, yes there are other mods, but the light flywheel made the most difference with throttle responce.
 

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kikoy said:
you guys ever heard of "FIDANZA"?...they make aftermaket fly wheels for almost any application... ...i tried asking them for my 2nd gen scort(1.9) and they quoted my me for 450 bucks...but its worth it cause you can replace the surface where the ckutch meets the flywheel....anyway here is the link http://www.aluminumflywheels.com/welcome.html
That's not too bad, I found one for my Si for 275 or so...for a 7.5 lb flywheel which will be shipped for under 300, that isn't bad...but 450 for a flywheel? must be rare or inlimited quantities.
 

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OK Jeff, here's an analogy.

Say you want to run the 100 yard sprint. But you've got a 25lb backpack on. With the backpack on you would run it in a certain time. Now let's say we take 20lbs out of the backpack, your fully rested and ready to run again and you're the same strength as what you were in the first race. You would be able to accelerate faster, but you'd also be able to run the 100 yards faster, right. The amount of work James is capable of doing didn't change, but the amount of time he did the work in did. Same idea with the flywheel.

hp=work/time (550ft-lbs/sec)

If I can do the same amount of work in less time, then my hp increases. So if you accelerate faster, you finish faster. If you finish faster, your time decreases. For the same amount of work, when your time decreases your horsepower will increase.

Confused :p

Matt 8)
 

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Quicker throttle response doesn't make a quicker car.

If you run a 15.0 quarter mile, take ten pounds off of your flywheel, you'll PROBABLY still run a 15.0 quarter mile, if not, a 14.9. The car will rev much faster, you'll have much quicker throttle repsonse, but it will also be more difficult to get a smooth clutch engagement do the the engines newfound "hyper-activity". I've driven 2 SHO's that have virtually weightless aluminum flywheels, and I've never stalled a car out so many times in my life.. they revved like they were on crack and caffeine, but they weren't any noticably faster than they were before they had 'em.
 
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