benefits of aluminum...
 

anyone have both aluminum driveshaft and aluminum flywheel? im just wondering what i should be expecting from both? the driveshaft is the ford racing and the flywheel...came from McLeod and i think its a 12 or 13lb one. will i feel the difference?

RE: benefits of aluminum...
 

your RPM's slimb and fall faster. so you can get into your power band quicker. you will have to drill a small hole in your TB the IAC will not be able to pick up the air quick enough so when you push in the clutch the RPM wont catch and alot of the time the car will die. it happened to my car and we just drilled a hole in the TB and that fixed everything

RE: benefits of aluminum...
 

Really?? holy crap thats good to know haha. can you describe or better yet show me a picture of where you drilled? how big of a hole? that sort of thing. so should i expect any increase in acceleration with all that rolling mass decreased?

RE: benefits of aluminum...
 

Acceleration will increase, but it will be easier to bog the engine, too. It will also be harder for the engine to maintain a steady rpm while cruising (decreased mileage being the largest indicator...if that matters to you).

RE: benefits of aluminum...
 

Why would you have any decrease in milage? The flywheel being lighter should not effect anything at crusing speed, other than possibly reducing the effort it takes to maintain speed.

Reduced weight, if anything, should increase fuel milage. The less weight you have to keep spinning, the less effort it requires, the less fuel used.

BTW, I noticed ZERO difference between my stocker and my aluminum driveshaft. The weight difference is not that massive.

RE: benefits of aluminum...
 

I read somewhere that 1 lbs of rotating weight is equal to 7 lbs of standing weight. So go with the aluminum!!

RE: benefits of aluminum...
 

yay reduced rotating mass!!! oh and im in the boat with 2000GT4.6 on the idea of reduced weight...thats serious though if you need to increase air flow on the stock tb...does anyone know if that holds true for the cobras?

RE: benefits of aluminum...
 

the only thing i can think of is newtons first law...once the heavier flywheel is in motion it will be harder to slow down thus maintaining the same speed created better gas milage....but i dont give a crap about gas milage lol. i already have the driveshaft in and i didnt notice any difference however when holding them my arm scale seemed to tell me the aluminum was quite a bit lighter. and the flywheel seems pretty damn light to compared to one i had for my old jeep...i guess we'll see shortly.

im kinda feeling like i wanna go with weight reduction instead of hp just to be different. anything else to do besides rear seat delete, i remember a thread and dont know where it went....

RE: benefits of aluminum...
 

To let you guys in on a little secret aluminum flywheel and driveshaft do absolutly nothing when you still have a stock engine. To get any benifit from the 2 you need a fully built engine that is able to spin higher. You may think that the lighter weight is better and will help it spin but it doesn't. It actually makes it harder for the engine to get up to speed becuase it uses the weight to get there. lighter wieght makes the engine work harder to get there. When you can get to a higher rpm is when the engine no longer needs the wieght to spin.

Also if you just buy an aluminum flywheel and through it on your engine it will throw off the balance and shorten the life of your engine.

RE: benefits of aluminum...
 

When you install a lightweight flywheel, there is no torque loss from the engine. End of story.

A flywheel, by it's very nature, is an energy storage device. It's purpose is to either absorb excess energy from the engine, or average out the energy being put into the transmission, when an imperfect rpm vs. gear/wheel-speed clutch engagement happens.

The energy is stored in it's mass. When you rev your engine, energy is used to move that heavy flywheel... energy that is not put to the wheels. The mass of the flywheel stores that energy by it's motion.

Thus, a lighter flywheel requires less energy to be moved, allowing more of the net total force produced by the engine to go to the wheels, making the car quicker.

But the important question is then, how does this jibe with "real world" experience?

Those who say their car feels quicker with a heavy flywheel are revving the motor above the correct gear/wheel-speed amount, and "dumping" the clutch. The heavy flywheel stored energy, and then transferred it to the transmission/wheels. Technically, during this engagement, the stored energy plus the engine input energy is more than the engine makes alone. The critical thing to realize is that this only holds true during the period of clutch engagement and is a "false torque" sensation.

That "false torque" sensation tricks human perception into thinking the car has more power, when the torque measurement of such an engagement style shows that the "false torque" jump up is immediately followed by a sub-normal torque dip as the heavy flywheel requires more energy input to re-accelerate than the lightweight alternative.

So you see, this is the reason why a lightweight flywheel car will walk away from a heavy flywheel car every time, regardless of how the initial clutch dump may "feel" stronger with the heavy flywheel.

RE: benefits of aluminum...
 

GT_Bob what your saying is what i was thinking "how could less rotational mass be a bad thing"



oxfordgt if the flywheel weighs less, and takes less energy to get up to speed, doesnt that mean more energy(or HP) that is available at the wheels? harder to spin? how is something that weighs less harder for the engine to spin?

RE: benefits of aluminum...
 

It absolutely does not take more energy to spin a lighter flywheel.

RE: benefits of aluminum...
 

thank you. i should try to get a dyno run before i put it on....

RE: benefits of aluminum...
 

We have a winner! A steel flywheel will help your engine maintain speed, where as a light flywheel will not. You will not see the difference between the two on a dyno, only in acceleration. No real-world highway will eliminate acceleration while cruising, which is why the mileage between the two is different.

How much difference it makes is a function of the diameter of the rotating mass. This is why your aluminum driveshaft won't make nearly as much difference as a flywheel.

That said, a heavier flywheel can be beneficial for mileage, but the limit before it becomes a burden is something that only expensive experimentation can resolve...which is probably something Ford already did and compromised on a flywheel weight that balances acceleration and mileage.

RE: benefits of aluminum...
 

so if no HP what about time in the 1/4 mile?

RE: benefits of aluminum...
 

Less rotational mass "should" mean quicker ET's because the motor can rev faster. Notice I said should. We use the Aluminum driveshaft more for strenght then weight with no real difference on the Dyno.

RE: benefits of aluminum...
 

My goodness gracious. Would you like it in sub-human plain language?

RE: benefits of aluminum...
 

nope, im just gonna be pissed if this expensive **** yields me no gain in any department...:(

RE: benefits of aluminum...
 

Ok heres the deal with the lighter flywheel. The heavier the flywheel the more energy it stores. So when starting off from a dead stop that energy is beneficial requiring you give less gas in order to get the car rolling. When you install a lighter flywheel you are reducing that "stored" energy. So when you let out the clutch that is putting more strain directly on the motor and not using any of that "stored" energy. Requiring you to give it more gas and a lighter clutch foot in order to not bog or stall. With that lighter flywheel your engine will accelerate and decelerate quicker. Therefore moving through the RPM's faster making your car go faster. As far as loosing MPG. this is true. the heavier flywheel at high RPM holds inertia therefore puttin less strain on the motor as it actually helps the motor spin. Look at it like this. Try pushing a 16Lb bowling bowl for a hundred feet VS. an 8LB ball. The 16Lb ball will maintain speed easier because of inertia but the 8Lb ball will get to speed quicker but require more power in order to keep it at speed.

RE: benefits of aluminum...
 

The bowling ball analogy is a good one...[/align][/align]Also, while we're talking about flywheels there are four others that don't seem to get discussed much on the Mustang boards, but that get a lot of discussion on the lighter weight sports car forums. A friend put some silly looking 20" wheels and 295 or 315 tires on his '98 Cobra and the reduced acceleration was immediately noticable to me, though he won't admit it.[/align]

RE: benefits of aluminum...
 

Good Lord...I don't think I've ever heard so much BS in one thread in my life. :eek:

RE: benefits of aluminum...
 

i have an aluminum flywheel, and i have to say that it definetly revs alot faster and deaccelerates alot fast, what i would like to see are some dyno sheets on a car before and after cause im so tired of seeing this topic debated so much... someone is obviously wrong....

RE: benefits of aluminum...
 

xDeuce.

RE: benefits of aluminum...
 

+ 1