Aluminum Flywheels

I have 90 integra and I'm building up the engine over the winter. One of the items on my list of possible mods is an aluminum flywheel weighing 9 lbs. I have been told several conflicting theories on these, so I thought i would ask the experts. This is a list of my current mods to help with the decision process on the flywheel:
- intake/exhaust/header
- port/polish head/intake (currently being done)
- ignition/wires
- aluminum pulleys
- enlarged throttle body
- fuel pump/pressure regulator

The following are the different "facts" I've been told about aluminum flywheels:
- they are only for turbo applications to help reduce turbo lag
- not for use on NA engines
- poor quality/wear out fast/never balanced properly
- work AMAZINGLY well on all applications
- for use only in race applications
... the list goes on

It would be extremely helpful if anyone could help shed some light on this issue. Thanx.

I f you don't mind some constructive criticism then I will throw in my :2cents: .

- intake/exhaust/header good, get a high flow cat like carsound.
- port/polish head/intake (currently being done) get some cams and valve springs to go with that, and new valves if you are thinking about big shots of N20 in the future.
- ignition/wires Stock ignition has been proven to be just as good as aftermarket ignitons on N/A motors
- aluminum pulleys Biggest waste of money and will destroy your rotating assembly if you change the crankshaft pulley
- enlarged throttle body good
- fuel pump/pressure regulator Not needed if you are not going FI, but if you do get one I would suggest the Walbro fuel pump and the B&M FPR.

I would aslo add some forged pistons while you have it torn apart, along with some rods if you can afford it. If you are gong N/A then i would also suggest a girddle for the crankshaft.

Now for the Aluminum flywheel, I have had 1st hand experience with them and I will never, ever, ever,ever as long as I live buy or let one of my friends buy one! Get a chromoly flywheel and it will last a long time and they (unlike aluminum) will be stronger than the stock flywheel. Exedy, and ACT both make some good ones.

That was my opinon, so don't get offened if you don't like anything that I put in there.

dude, no offence taken, thanx for the advice, any info i get is helpful. much appreciated.

r the chromoly flywheels made light weight also?

r the chromoly flywheels made light weight also?


Yep :bigthumb:

r the chromoly flywheels made light weight also?

my question is how much do they compare in price to the aluminum????and where would you go about getting one..just on the internet???cause i was gonna go put in a new flywheel in about a month..

http://www.groupbuycenter.com/buy.aspx?id=14128 come on guys use some searching skills :icon16: BTW this is one of the best ones on the market right now IMO and you can also get them to put together a clutch/flywheel package too. :bigthumb:

Looks like I made a good choice on the ACT flywheel then. I've heard aluminium flywheels warping, so I really thought hard before getting a lightened flywheel.

Get a chromoly flywheel and it will last a long time and they (unlike aluminum) will be stronger than the stock flywheel. Exedy, and ACT both make some good ones.[/color]

That was my opinon, so don't get offened if you don't like anything that I put in there.Don't ever get a steel flywheel. Stick with aluminum. Many people have been seriously injured from light wheight steel flywheels, and I'm pretty sure some have died. When steel(chromoly) is pushed to it's limits, it doesn't "give" or deform like aluminum does, it shatters. If you are going to be ignorant and still go with steel, then atleast get a scatter shield. Here (http://www.bettendorf.com/~mrbone/pictures/PicHost/flywheelboom.wmv) is what can happen if you run a lightened steel flywheel. Good thing he had a scatter sheild...

Don't ever get a steel flywheel. Stick with aluminum. Many people have been seriously injured from light wheight steel flywheels, and I'm pretty sure some have died. When steel(chromoly) is pushed to it's limits, it doesn't "give" or deform like aluminum does, it shatters. If you are going to be ignorant and still go with steel, then atleast get a scatter shield. Here (http://www.bettendorf.com/~mrbone/pictures/PicHost/flywheelboom.wmv) is what can happen if you run a lightened steel flywheel. Good thing he had a scatter sheild...

Those are cases where the stock flywheels are lightened at a machine shop. And also the stock flywheel and the Chro-moly are totaly different. The chro-moly flywheels "(quality brands) are at the least 2 times stronger than the factory flywheel and some times as high as 10 times. The aluminum flywheel is not near as strong as the chro-moly. Get some real info about why not to use a product or stop bashing it!


Go do some reasearch before you try to correct someone noob :newbie:

LMAO, it's funny how some people think number of posts means a damn thing. That being said...
High carbon steels tend to be more fragile than lower grades. The steel flywheels mentioned here are a good example. You might note that NASCAR only allows mild steel tubing for the roll cages in the cars. This is because they do not want contact to break a tube. It's much preferred that the tubing deform and "give".
When you make a steel part exceptionally light weight, you're going to sacrifice overall strength of the component, just as you'd do with any other lightened components.
If you take a look at damned near all the components that the Jap tuning experts sell, it should painfully clear that their "stuff" is designed for what "they" do in Japan.....run N/A race cars on smooth tracks. Their parts (including engine goodies) are know as 5,000 mile "specials" everywhere else in the world. They are not designed for everyday driving and repeated cycling.
On a flywheel, you can't have hi-grade steel contacting and wearing with hi-grade steel. This is just one of the incompatibility problems that exists between the flywheel teeth and those of the starter. Those components will destroy each other in a relatively short time span.
On the flywheels, once you have created a tiny fracture at the OD, the crack will continue to spread into the center, especially since there is considerable pressure (pressure-plate and disk) and rotational forces working on it.
This is a potential disaster waiting to happen.
An aluminum flywheel might be a touch heavier than the light-weight steel units. I suspect that, if you look where a flywheel's mass is relative to the center of the crank, the aluminum flywheel's mass is probably located a greater distance from center, so it's more difficult to accelerate (than light-weight steel flywheels).
The aluminun alloys used for flywheels are far more deformable and MUCH less likely to crack or break.

The aluminun alloys used for flywheels are far more deformable and MUCH less likely to crack or break.

Ok I have removed 2 aluminum flywheels from people's cars that were cracked and some warped, and I have never had to remove an chro-moly flywheel from a car for any reason. The aluminum's down fall is that is does not disapate heat properly and it WILL warp and it WILL crack from the excessive heat that is not being disapated properly and it WILL cause problems. And for the "On a flywheel, you can't have hi-grade steel contacting and wearing with hi-grade steel" the ring gear is not made of the same material as the chro-moly flywheel it is usually the stock or stock replacement ring gear.
And yeah maybe the aluminum is a better choice for a car that is torn down and rebiult after every race but here in the more common practical world the chro-moly would be better.

Also the Japenese manufactors use aluminum huh, well Toda and Spoon use chro-moly so who are these "Jap tuners", because Spoon is the #1 honda/acura tuner in japan


And you just assume that because I have a high post count that I think I know something, well I don't know it all but I do know alot.

Here is some more info for you http://www.todaracing.com/topics/articles/flywheel_design.html

Do you have any fisical info to direct people to about your opinon?

Yea i hear that chromoly is the way to go with flywheels. I dont have any experience cuz right now a lightweight flywheels costs to much money for me right now so i dont have one. I hear stories where the aluminum ones arent balanced well and warping and blah blah blah. In my opinion i would get a chromoly flywheel.

Oh yea i got a question. Does anyone ever hear that if u get a light weight flywheel that when u rev ur car and let it come back down sometimes the car dies out cuz it loses all its inertia so fast? Thats a story i heard but i never knew that could happen.

Oh yea i got a question. Does anyone ever hear that if u get a light weight flywheel that when u rev ur car and let it come back down sometimes the car dies out cuz it loses all its inertia so fast? Thats a story i heard but i never knew that could happen.

I ahve not heard of that happening but I can see where it might happen if you have a flywheel that is too light, but if you saty with the 12.5 ACT then you will be fine. However with any type of light weight flywheel you will notice that the motor will rev faster, well it will decend in revs quicker too, so you need to be a fast and acurate shifter.

Your engine should never stall from having a light flywheel. If it does then you need to either change you idle timing, injector pattern or raise your idle rpm.

Is it me or have there been an obsene amount of "flywheel" threads lately?

Is it me or have there been an obsene amount of "flywheel" threads lately?

YES there have been. Err ...... SEARCH and READ people!

YES there have been. Err ...... SEARCH and READ people!

You should make your Avatar a MASSIVE SIG PIC THAT NO ONE SHALL AVIOD AND ALL MUST OBEY!

You should make your Avatar a MASSIVE SIG PIC THAT NO ONE SHALL AVIOD AND ALL MUST OBEY!

HAHA no I am not that much of an search nazi but I do believe that people could read other posts that are titled the same as theirs. Just maybe, just maybe the info they are looking fo ris in there, and if not then post in that thread. :2cents:

Even that is still hard for some...... But maybe someday..... someday.....

Ok I have removed 2 aluminum flywheels from people's cars that were cracked and some warped, and I have never had to remove an chro-moly flywheel from a car for any reason. The aluminum's down fall is that is does not disapate heat properly and it WILL warp and it WILL crack from the excessive heat that is not being disapated properly and it WILL cause problems. And for the "On a flywheel, you can't have hi-grade steel contacting and wearing with hi-grade steel" the ring gear is not made of the same material as the chro-moly flywheel it is usually the stock or stock replacement ring gear.
And yeah maybe the aluminum is a better choice for a car that is torn down and rebiult after every race but here in the more common practical world the chro-moly would be better.That site you supplied only supported what I had to say about steel flywheels. I'm not trying to be mean, but where are you getting all your false information? Last I heard, aluminum disapates heat better than steel. I've been running aluminum flywheels in my Civic since 1996...and it still has the same flywheel in it. It's never been resurfaced either. You can buy replacement friction plates for aluminum flywheels. I've seen more people buy CM/CC/Fidanza aluminum flywheels over the last 7 years because their ACT discs shed material, damaging the flywheel surface and the pressure plates.

"I started to say that if I sold chromoly flywheels, I'd tell people that aluminum was no good....but I won't sell products that aren't what I'd use, or inferior in any way, so I can't."

Also the Japenese manufactors use aluminum huh...I was talking about chrom-moly, not aluminum, read through the post more thoroughly...

HAHA no I am not that much of an search nazi but I do believe that people could read other posts that are titled the same as theirs. Just maybe, just maybe the info they are looking fo ris in there, and if not then post in that thread. :2cents:


YES there have been. Err ...... SEARCH and READ people!


"use those searching skills"


come on whtteg....stop being such an old grumpy guy......your self righteousness just oozes out of your quotes.....if someone asks you where to get a chromoly flywheel because you posted about one...just answer them, and be glad you can share your knowledge..dont be a prick...if they wanted to hit up google or something and search through the oh...id say......55,000 different sites that just refer to a chromoly flyhweel and prices.. obviously had never heard of the steel flywheel and so you its your obligation if your gonna answer and contribute to this thread to be a cool guy and answer....they wouldnt need you....i understand that you think everyone should look up old threads..which i do often...but heaven forbid you just let someone know if they ask every once in a while......IMHO!!!!!

you and i both know...that in any hobbie or field its a cycle.....you learn from someone else and they teach you...and help you get your feet wet...and then you pass it on....or your not fulfilling your obligation to keep the idea going

YES there have been. Err ...... SEARCH and READ people!


"use those searching skills"


come on whtteg....stop being such an old grumpy guy......your self righteousness just oozes out of your quotes.....if someone asks you where to get a chromoly flywheel because you posted about one...just answer them, and be glad you can share your knowledge..dont be a prick...if they wanted to hit up google or something and search through the oh...id say......55,000 different sites that just refer to a chromoly flyhweel and prices.. obviously had never heard of the steel flywheel and so you its your obligation if your gonna answer and contribute to this thread to be a cool guy and answer....they wouldnt need you....i understand that you think everyone should look up old threads..which i do often...but heaven forbid you just let someone know if they ask every once in a while......IMHO!!!!!

you and i both know...that in any hobbie or field its a cycle.....you learn from someone else and they teach you...and help you get your feet wet...and then you pass it on....or your not fulfilling your obligation to keep the idea going
I have helped more people on this board than you might ever think about helping! And I am stating that there have been a lot of threads about flywheels and the questions in those threads are basically the same, so why not just read that one and not post another thread? Also I have been around on this site for a long time now and I have seen all the questions, I have not seen a question that I have not seen in the past posted up in here in at least 1yr. Also I have answered probably every question that has been posted in here at one time or another. The "cycle" as you call it is not working, people are coming on here and asking a bunch of questions then they leave and don't help anyone out. It gets rather redundant to see the same questions being asked time after time.That is how I see it as well as most of the members who have been here for some time now. I am sorry if you don't like it or if you don't like me but you don't have to :icon16:

BTW: When I say search and read I mean on this site we have this little box that says search on it, type in what you are looking for and it will give you the the posts that contain the answers instantly, rather than posting it again and waiting for the answer, you will get it instantly.

That site you supplied only supported what I had to say about steel flywheels. I'm not trying to be mean, but where are you getting all your false information? Last I heard, aluminum disapates heat better than steel. I've been running aluminum flywheels in my Civic since 1996...and it still has the same flywheel in it. It's never been resurfaced either. You can buy replacement friction plates for aluminum flywheels. I've seen more people buy CM/CC/Fidanza aluminum flywheels over the last 7 years because their ACT discs shed material, damaging the flywheel surface and the pressure plates.

"I started to say that if I sold chromoly flywheels, I'd tell people that aluminum was no good....but I won't sell products that aren't what I'd use, or inferior in any way, so I can't."

I was talking about chrom-moly, not aluminum, read through the post more thoroughly...

Not 1 thing on the site I posted supported anything you were saying. :screwy:

so if were to change my flywheel then i should change the clutch as well too right? I heard that if u just change the flywheel but leave the stock clutch then u will get some problems down the road. I already kno it makes more sense to change the clutch and flywheel at the same time to save hassle since both are right there so lets leave that out of the question.

so if were to change my flywheel then i should change the clutch as well too right? I heard that if u just change the flywheel but leave the stock clutch then u will get some problems down the road. I already kno it makes more sense to change the clutch and flywheel at the same time to save hassle since both are right there so lets leave that out of the question.

You need to contact the manufactor of the flywheel and make sure it is compatible with the stock clutch, some say they are not. Also i would never change the flywheel and not change the clutch, it is so much easier to do it at the same time. And yes I know you said leave that ot of the equation, but i threw it in there anyway, sorry :p

well im sorry whetteg i did not mean at all to question your internet automotive site credibility or knowledge...im sorry that you are so worked up over myself and my one comment.....i respect you and your vast amount of insights.....you have helped me in the past actually a few times..i have sent you private messages and you answered me....and im glad...and like you said in your post that was deleted.. in reference to yourself....."i have helped more people than you could ever dream of helping" or something to that effect....and i do not doubt that.....im sorrry that you have felt the need to get very very defensive and start the whole flame towards me.....i thank you for helping me....and others..even though some times we dont take the effort to look it up....or we dont find it when we look for it....i dont hate you or dislike you as you said.....and i plan on looking into a steel/chromoly flywheel because of your posts..thanks
sincerely copasetic

copasetic808, from an objective 3rd party point of view, I can see why whtteg got defensive. Your post was conflicting. You seemed to post at first like you agree'd with him, then went on to lectur him about "the cycle" and "no one wants to search google and get 55,000 responses(when he ment search af, not the web, as he explained later). When you combine all that with the fact you called him a grumpy old grump, it seemed like you were being splitful. In a way, it did come accross as spiteful, whether you ment it to or not. Spiteful comments are often intrperated by people as a personal attack on them. I mean go back and re-read the post. I have no part in the discussion, and that's how it come across to me. When you see it from this perspective, you can see why he got defensive. I don't think it was just the comment itself that worked him up. He's usually a level headed guy. It was the way you said it, the way you delivered it. It's a normal reaction to someone being treated like that. Frankly, I agree with him: people need to search and read before going and asking the same questions over and over. The more you know when you ask, the more likly it is you'll get better answers. In the end, you'll know more.

copasetic808, from an objective 3rd party point of view, I can see why whtteg got defensive. Your post was conflicting. You seemed to post at first like you agree'd with him, then went on to lectur him about "the cycle" and "no one wants to search google and get 55,000 responses(when he ment search af, not the web, as he explained later). When you combine all that with the fact you called him a grumpy old grump, it seemed like you were being splitful. In a way, it did come accross as spiteful, whether you ment it to or not. Spiteful comments are often intrperated by people as a personal attack on them. I mean go back and re-read the post. I have no part in the discussion, and that's how it come across to me. When you see it from this perspective, you can see why he got defensive. I don't think it was just the comment itself that worked him up. He's usually a level headed guy. It was the way you said it, the way you delivered it. It's a normal reaction to someone being treated like that. Frankly, I agree with him: people need to search and read before going and asking the same questions over and over. The more you know when you ask, the more likly it is you'll get better answers. In the end, you'll know more.

thanks for your input.....i have taken your advice into consideration.however you use the word OBJECTIVE...a little loose...and yes he was talking about a search engine...look at the beginging of the thread...when i asked how much is the price comparison..he said use your searching skills people...and pasted a website....your refering to later on in the thread..when you say old AF forums and threads......but thats fine......
i stand corrected after all just yesterday in the words of whettg i was a noob.... i "Go do some reasearch before you try to correct someone noob"

Ok guys this is not going to get anybody anywhere. Yes in the post on the 1st page I was talking about using google, but come on guys I did a search on google for that and it was like the 3rd or so search result. But anyway, I have no hard feelings towards anybody, I am a very understanding guy and I like to work things out with people. But as far as some people go, I try really hard to keep the wrong information corrected, because if I don't then some one who does not know any better may take the wrong information and mess up his car or worse get hurt or hurt some one else, which this does not apply to you copasetic808, I was just throwing that in so hopfully you guys could understand more about why I keep coming back at people. Now to be clear I am not saying that you, copasetic808, posted any wrong info, just wanted people to better understand me.

Are we all cool now? :icon16:

Ok guys this is not going to get anybody anywhere. Yes in the post on the 1st page I was talking about using google, but come on guys I did a search on google for that and it was like the 3rd or so search result. But anyway, I have no hard feelings towards anybody, I am a very understanding guy and I like to work things out with people. But as far as some people go, I try really hard to keep the wrong information corrected, because if I don't then some one who does not know any better may take the wrong information and mess up his car or worse get hurt or hurt some one else, which this does not apply to you copasetic808, I was just throwing that in so hopfully you guys could understand more about why I keep coming back at people. Now to be clear I am not saying that you, copasetic808, posted any wrong info, just wanted people to better understand me.

Are we all cool now? :icon16:
yes definitely.....no hard feelings...

Not 1 thing on the site I posted supported anything you were saying. :screwy:Yes it does, you just don't know how to interpret the information it's giving you. They give you the information and say "it's good", so you think it must be, when you don't even know what they're talking about. That whole site is just one big add with misleading information. First of all let's look at the heat treating. They heat treat it to make a higher quality steel, but during that process they also make the steel significantly more brittle. That's a no-no when something is to be spinning at high speeds, expanding and contracting from heating and cooling. Brittle steels also don't take expanding and contrating lightly, which is why they are more prone to "crack" than the aluminum flywheels. It's a grenade waiting to go off. I would never allow anyone I know or love to be put in that situation.
And for the "On a flywheel, you can't have hi-grade steel contacting and wearing with hi-grade steel" the ring gear is not made of the same material as the chro-moly flywheel it is usually the stock or stock replacement ring gear.It says right on the site you supplied, "With finally the 2nd and final heat treatment giving the clutch face and the gear teeth a greater wear and durability rate." No matter how much you want to think it's a "good thing", it just isn't...

Ok then it also says that they let it cool very slowly which bring flexability back to the flywheel. Did not care to put that in there did you?

Whtteg, it's all good, lol. I just felt you where in the right. You know I'll have your back in a situation like that. I felt obligated to get your back, lol. It's all good though, no hard feelings towards anyone.

Whtteg, it's all good, lol. I just felt you where in the right. You know I'll have your back in a situation like that. I felt obligated to get your back, lol. It's all good though, no hard feelings towards anyone.

Oh I understand, and I would like to thank you as well. It really took me by surprise that he said all of that. Maybe it was just some mis-understanding between us, I dunno, but all taht matters is that everyone is cool with each other. :bigthumb: We will always get more accomplished this way.

We will always get more accomplished this way.

Very True...now if everyone else on here can understand this...lol.

i am thinking of changing my fly and clutch since they are going but the fly i wanted is 8.8lbs. Is there anything bad that could happen from sporting an 8.8lb flywheel on a daily driver with only basic mods? I dont wanna F my car up too much but if it is all safe and cool to sport one then i will. people are saying 8.8 is only for like racing but other are saying it will be safe and cool.

The 8.8 is better suited for race apps. It will not hurt your car persay but it will be a little agrivating, the motor will drop in rpm real fast.