aluminum flywheel..good or bad?

[chineseb0i]

hi,
i've heard that aluminum flywheels aren't really that good seeing how they are pressed on and held by screws. I heard they're good for racing and for temporary use like drag racing or what not. I'm planning on using it with my ACT street/strip clutch and was wondering if I should stick with the stock flywheel or get the findanza 11 lb. flywheel and use it for street use. I heard that steel billet flywheels are used for more street use. What do you guys have to say about aluminum flywheels for street use? yay or nay? and if you guys do have the findanza flywheel, any problems? thanx

[nrcooled]

I have never read anything about aluminum flywheels being detrimental to an engine or tranny. I have had no issues with mine.

Reducing rotating mass properly (i.e. evenly) can't hurt the engine. What reasoning do you have for thinking it would?

[chineseb0i]

i was looking on ebay actually and found a billet steel flywheel for an sr20det and under the description the guy wrote about the aluminum flywheels being prone to error. Here's the link:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33732&item=2421422315

that's why I had a question about it and i appreciate your response and input. I have a findanza 11 Lb. flywheel on it's way so i guess i'll put it in..unless anyone else has any more input on the aluminum vs billet steel flywheel issue.

Thank you

Sincerely,
Solomon

[RedlineRacer]

11 lb. flywheel is way too light. I've read the lightest you should got is around 15 lb. If you go too light, your flywheel will have no enertia. So, when you change gears, your RPM's will drop sooo fast.

[drifties151]

Originally posted by chineseb0i
hi,
I heard they're good for racing and for temporary use like drag racing or what not.

i dunno where you heard that they're good for drag racing, but thats not right. it depends what kind of racing you want to do. for auto x and street driving, aluminum flywheels are great. i wouldnt buy one for drag racing though. Because lightened flywheels do not store as much inertia, they are not suited for hard launching, like in drag racing. just my .02 hope this helped you out a lil.
-terry

[chineseb0i]

i am using it mainly for street use. I guess if I do use it for street use, I'll need to shift quick before i lose all my rpms :D thanks for the responses..i appreciate it guys. I hope to get a short throw shifter in the future too. Hopefully that will help the rpm loss when shifting with a lightened flywheel. I hope to install the ACT clutch and findanza flywheel in a week or two. I'll let you guys know how things go and the difference and thanks again for your help.

Solomon

[Lethal]

Well I don't have one installed behind a Nissen but I do behind a Toyota 4AGE powered clubman. As far as problems, I've had none and it weighs 4.9Kg and the car is used for both street an track. The only time you'll notice a difference is when you do a heal/toe gear change, engine spins up quicker. In gear (any gear) you will not notice any difference.

In my view unless you after every speck of performance it simply isn't worth the cost. Spent your bucks on other things that will make a difference.

[Red]

Well I have one on my 95 240sx. I love it.

And if you are holding in your clutch long enough to drop your RPM's that much while shifting up gears.... you need to learn to shift.

Anyways if your rpms do drop... you can just tap your gas and it pops right back up.

And down shift rev matching is quicker then with a normall flywheel. I dont do that heel toe crap.. My feet are to big.

Read the reviews section.

[drift freaq]

ok guys, first off putting in to light of a flywheel on a street machine is a mistake. Unless you love having no bottom end torque. On a track car it does not matter because they are always in the mid to upper revs anyways.
Ideal weight for a street KA engine is around 15-16lbs ideal weight for a street SR is around 12-13 lbs (SR flywheels are lighter than the KA version to start with).
These weights will give you a lot more responsive throttle and you will gain back some of the HP loss to parasitic drag. You will not sacrifice your bottom end torque at these wieghts.
thats what you should shoot for. As far as the inertia comments go they are true in the sense that the inertia is part of what gives you bottom end torque. Being bad for the engine ? No. Being bad for street use, where bottom end torque can be your friend ? yes.

[Pudula]

If you are running an sr20det, based on my research on my build-up, stock flywheel is better. This is simply because, the lighter flywheel will allow the engine to rev faster, so the turbo does not get as much time to spool, creating a loss of power from the turbo...or something like that :)

[Lethal]

Red.....heal/toe is the kind way of matching engine/input gearbox shaft speed and keeping shift stress on a gearbox to a minimum. Sure you can straight shift but in the end its going to catch up with you. You must have damn big feet !

Other than that I think we are saying the same thing, lightweight flywheels improve an engines unloaded rpm response and not a lot more.

If your still keen to buy one the link below will take you to a site that has the details of the guy who built mine, first class job and it cost about $500 Aus or about $250 US.


http://www.billzilla.org/shopping.html

[Bill Roberts]

Rubber block on the gas pedal vastly improves heel to toe action.

[twitchy]

could you remove the flywheel?? or do you need it..cause on some cars, though its rare, they dont have one (IE McLaren F1)

[kandyflip445]

Originally posted by twitchy
could you remove the flywheel?? or do you need it..cause on some cars, though its rare, they dont have one (IE McLaren F1)

Well I don't know about other cars but on ours you can't at all. The flywheel also acts as the friction surface for the clutch assembly.

[Red]

I dont see how turning my 21 lb. Flywheel into an 11 lb. Flywheel hurt my bottom end torque one bit? Less rotational mass frees up power and torque… Have you ever looked at the dyno of a car with the lightened pulleys on? If you do you will notice that reducing the rotational mass of an object makes it easier to spin… Therefore less power is wasted in keeping your flywheel spinning and more is transferred to your wheels.

The only thing a lightened flywheel will do is reduce your launch. Because of the reduced mass there will be less energy stored in the spinning flywheel to transfer to your clutch. So you will have to rise your RPM’s a little bit higher to launch and slip it in. Whoopee…

On a street driven car I don’t see how a lightened flywheel can adversely affect you. Unless you’re a total tard and think every stop light is a freaking drag race. Normal clutch engagement should prove to have more power on tap once your clutch is fully disengaged.

I just want some #'s so we can truly see the affect of it. If I had a base dyno of my car befor mods I could do this... But I don't.

EDIT: made an error

[old_s13]

Red> Drive a car with too light of a flywheel, YOU will notice a difference.. or so I hope. Some weight is needed to keep the engine spinning, otherwise you will constantly be downshifting to keep the car in higher RPMs to sustain power -- its as simple as that. Anyone who drives canyons will learn or want to know how to heel/toe, its a severe advantage if you know how to properly do it.

Bill> Why strap a block on your gas pedal when you can just BEND the gas pedal? :)

I use a lightened OEM clutch, they removed a good 10 pounds and the material removed from the back of the flywheel was stepped. This is a low cost improvement over stock. Of course, you can always get a NISMO clutch/flywheel set -- get ready to spend bank for some NICE stuff.

- Mike

[Red]

Originally posted by old_s13
Red> Drive a car with too light of a flywheel, YOU will notice a difference.. or so I hope. Some weight is needed to keep the engine spinning,

Wow I talk as if I have driven a car with one… Ohh wait did you ever notice my sig?? Yeah I HAVE a light flywheel and all I notice is vast improvement over stock… Ya know they only make an 11 lb. one for the KA... So its not like its guna get any lighter.

[Hybrid]

It seems to me some people really don't have a grasp on the concept of what inertia is...a resistnace to a change in motion(direction, speed, etc.). I have driven several cars with lightweight flywheels...my Honda had a 9lb and honestly I expected a night and day difference in the speed at which the engine lost and gained revs and it was not incredibly noticable. I never had a problem between shifts, I don't know who the ham fisted drivers are who have these problems but, it was never a problem with me. After riding in a car similar to mine with a stock flywheel I did notice that the RPM's lingered longer than mine did when you let off the gas pedal. And I also felt a noticeable difference in acceleration I thought this was simply my head but, I was skeptic it would make a difference. In first and second it was really apparent. I know that according to the formulas this should have the greatest affect on the acceleration due to the gear multiplying factor but, first and second didnt allow enough time for the engine to pull through a gear long enough to notice. But third and fourth the car seemed noticably stronger.

As far as drag racing goes having a light flywheel may help or hurt you depending on your car...if you have a serious wheelspin problem a light flywheel will allow more energy to be absorbed as the tires move the vehicle resulting in a gradual application of torque to the wheels wheres, a heavy flywhell would be more abrupt resulting in wheelspin. The opposite applies if your car has too much traction.

[ckyfish]

Originally posted by Hybrid
It seems to me some people really don't have a grasp on the concept of what inertia is...a resistnace to a change in motion(direction, speed, etc.). I have driven several cars with lightweight flywheels...my Honda had a 9lb and honestly I expected a night and day difference in the speed at which the engine lost and gained revs and it was not incredibly noticable. I never had a problem between shifts, I don't know who the ham fisted drivers are who have these problems but, it was never a problem with me. After riding in a car similar to mine with a stock flywheel I did notice that the RPM's lingered longer than mine did when you let off the gas pedal. And I also felt a noticeable difference in acceleration I thought this was simply my head but, I was skeptic it would make a difference. In first and second it was really apparent. I know that according to the formulas this should have the greatest affect on the acceleration due to the gear multiplying factor but, first and second didnt allow enough time for the engine to pull through a gear long enough to notice. But third and fourth the car seemed noticably stronger.

As far as drag racing goes having a light flywheel may help or hurt you depending on your car...if you have a serious wheelspin problem a light flywheel will allow more energy to be absorbed as the tires move the vehicle resulting in a gradual application of torque to the wheels wheres, a heavy flywhell would be more abrupt resulting in wheelspin. The opposite applies if your car has too much traction.

0WN3D! No seriously though, hes right though. So go buy your lightweight flywheel if you really want it, dont let others discourage you on their lack of basic physics knowledge.

[drift freaq]

this whole thread is starting to crack me up. First off I have first hand experience with engines with flywheels that were to light. you did lose inertia which translates in to losing bottom end torque. I.E. technically you have not really lost your torque its been transferred to a different range in the rev band inertia wise. hmmm thats why track cars have lightened flywheels. It keeps the inertia down and the revs up. Translates to less bottom end torque. Now what are you guys missing here in the physics?
Oh ya your gonna compare a Honda engine (torqueless wonders to start with, with high lift cams stock )to a Nissan engine? Don't even get me started there . You can't run that comparision because the inherent build of the engines is so much different in terms of HP and torque . Its like comparing Apples to Oranges.
I stand by first hand experience in the field with stock flywheels ,extra light flywheels and midrange flywheels. Any you young bucks want to come down to socal and prove me and Old_s13 wrong? Don't bother. I was playing with cars when your butt was in diapers.
Oh ya mr KA with 11lb flywheel I bet your happy your KA finally revs half way decent because you have taken a lot of low drag off it . I bet that makes you feel like there is no difference because your so rev happy now you forgot. hahahahahaa:doh:
Been there, seen it, done it . I don't think most of you can that.

[Bill Roberts]

Old, I don't like bending things....


:D


Block is removable, weaking the throttle pedal strut is not..

I see your point...but not for me, don't want to stress a cable at full throttle.

I already removed the block (behind the pedal) so I know about snapping cables and have calibrated it for the top block. Some thought and experience actually went into this...somewhat..

It's all about what you get used to (flywheels, pedal extenders, cable management, my technique in heel toe) and what you are willing to get used to.

:D

[old_s13]

Bill, you bend the pedal itself.. not the stop at the bottom of the pedal -- you need that so you dont put unecessary stress on the cable. :)

[SpeedMonkeyInc]

Red and Hybrid know whats going on. Lightweight flywheels are good. It is true that you need some mass there in order to keep the motor idling, but whats all this low end torque stuff? Must be one of those old hot-rodder myths like "backpressure makes torque"
Anyway, I had a 7.5lb flywheel on my Honda and it was really nice. Revved a little faster and picked up in first and second gear better. And from low revs, the motor would pick up faster (3000-3500RPM) You gotta shift fast all the time is the one real drawback. If you are not paying attention its easy to buck the car like an amateur clutch monkey.
If your goal is to go fast weight is one of the enemy.