Lightened flywheel

[Jonny5]

Anyone have any experience with them. Pros or cons. Over heating or idle problems.

 

[designed2survive]

@Jonny5

Pros: if you just bash around, none! If you race, may be. Still needs to be proven beside just lightening the whole car weight by a couple of ounces.

Cons: none, except price. Of course I'm referring to a properly lighten and truly balanced flywheel. If not, well it's a recipe for a short engine life.

 

[Jonny5]

I have read that factory new ones are not balanced. This came from site selling lightened ones. I wouldn't be surprised if my cy wasn't balanced. Lol. I'm thinking a diy balancer would be closer than a new "unballanced" flywheel. Has anyone noticed any machine marks on a new cy engine. Could see a zenoah would be more likely balanced but not sure. Just grinding away and not making and effort to ballance could easily destroy any engine.

 

[crankestein]

I got to find the thread, this guy went extreme, and found no benefit to having a lightened flywheel, and if so was very minor.

IMO, the flywheel does at least three things;

absorbs heat (heat will travel to where the temperature is cooler), vibration (a damper) and torque

In fact, I am thinking of installing more weight with epoxy, jb weld, and balance once done. The engine may get slower during pick up, but once its high in the revs, the more weight it will carry on with the momentum.

 

[Jonny5]

Ya not sure how much you would see in gain. Automotive you see a small gain. Like around 3 to 5 hp in a 200 hp car. Now that don't seem like much but it is because like most mods you only gain hp in small window of rpms. But.. with light weight flywheels and light weight pulleys and also under drive pulleys you see a gain across the entire rpm range. So 2% gain on a 5hp engine you would probably just write off as no change and dyno fluctuations.

Another thing to consider is most light weight flywheels has a portion of fins removed. Should also be less energy to move air. But how much would you really gain..... not to sure.

 

[crankestein]

Have you ever seen the flywheel of a 4 cylinder vs. a V8 engine?

Which one do you think is heavier?

 

[Jonny5]

The manufacturer weight can very. Like a civic and neon won't weight the same. Would say most v8 would be more heavy. But not all. Bigger factor from 4 to 8 would be the diameter of the flywheel. Bigger diameter flywheel on most v8 engines. Bigger diameter can be more than actual weight. Keep in mind that only manual transmission cars have flywheels. Auto have flex plates and for the most part can not be lightened enough to make a difference.

 

[crankestein]

The piston port design is a very unbalanced engine.

Messing with the flywheel is detrimental to the longevity of the engine. The vibrations need to go somewhere, but although may not seem like it, the FW does the job of a dampener, and dissipates heat (it needs to go somewhere).

A two stroke engine is a high revving low torque motor, vs. a four stroke where the power is at the lower region of the rpms.

A SVT Cobra uses the same or smaller flywheel compared to a 4-cylinder Civic. A FW carries momentum and helps maintain the rpms up out of throttle, else they drop immediately. If you are looking for more power, raise the exhaust port about 1mm, and give it a v-shape, work on the transfer ports smoothing out and reduce the thickness of the bridge, blue print the engine. With those minor changes, you will have one screaming engine with the right pipe and 8k clutch spring.

 

[Jonny5]

The piston port design is a very unbalanced engine.

Messing with the flywheel is detrimental to the longevity of the engine. The vibrations need to go somewhere, but although may not seem like it, the FW does the job of a dampener, and dissipates heat (it needs to go somewhere).

A two stroke engine is a high revving low torque motor, vs. a four stroke where the power is at the lower region of the rpms.

A SVT Cobra uses the same or smaller flywheel compared to a 4-cylinder Civic. A FW carries momentum and helps maintain the rpms up out of throttle, else they drop immediately. If you are looking for more power, raise the exhaust port about 1mm, and give it a v-shape, work on the transfer ports smoothing out and reduce the thickness of the bridge, blue print the engine. With those minor changes, you will have one screaming engine with the right pipe and 8k clutch spring.

Cobra has 22 lb FW with 10.5 clutch disk
Civic has 17 lb FW with 8 inch disk
So v8 weighs more and likely is bigger around. Generally v8 FW will weigh more and have more rotating mass due to accommodating the larger disk size for more torque. Their is exceptions to the rule like turbo cars and just design changes.

I know vibration will hurt a motor but I was getting at is that I have read that the people cy or zenoah FW is not balanced from new. Was thinking it may be beneficial to just diy ballance them closer than the unbalanced cast.

 

[crankestein]

http://forums.corral.net/forums/94-95-tech/1204745-stock-flywheel-weight.html
Post #10, 20 pounds
Post #11, 20 pounds
Post #16, 17 pounds

A 4 cylinder has about 80 to 120HP, compared to a V8 that possibly twice the HP or more. There is a reason why a high revving engine has a heavier fw, hp vs. fw weight, than a V8. Lightening the flywheel will come at a price, whatever you gain on one side, will be lost in another area. IMO, either balance and leave it alone, or make it heavier and balance it. Honestly best bang for your buck is to port the top end, with a good pipe.

Hondas are revving at 8k and above, vs. a SVT that its in the lower rev range.

 

[Jonny5]

https://www.svtperformance.com/forums/threads/some-different-clutch-and-flywheel-weights.1067180/

OR

Think this is a bit more accurate than random chat.

You have your specs backwards.
Do a bit more looking into before you try to tell them they are wrong.

 

[Jonny5]

http://forums.corral.net/forums/94-95-tech/1204745-stock-flywheel-weight.html
Post #10, 20 pounds
Post #11, 20 pounds
Post #16, 17 pounds

A 4 cylinder has about 80 to 120HP, compared to a V8 that possibly twice the HP or more. There is a reason why a high revving engine has a heavier fw, hp vs. fw weight, than a V8. Lightening the flywheel will come at a price, whatever you gain on one side, will be lost in another area. IMO, either balance and leave it alone, or make it heavier and balance it. Honestly best bang for your buck is to port the top end, with a good pipe.

Hondas are revving at 8k and above, vs. a SVT that its in the lower rev range.

I agree with porting but don't know what I'm doing. With port timing and whatnot. Doing the work is easy and I have plenty of tooling to do it. but don't have specs to make it to. I have a 3in1 mill/lathe and turn table so doing flywheel would be easy. Would think balancing shouldn't be to bad if it is true that the oem one isn't balanced

I do find it quite funny you suggest making fw weigh more. Adding more rotating weight will "almost" always slow you down.

 

[crankestein]

Either or, its a few pounds, not much of a difference... power to FL weight, the 4 cylinder is heavier.

Anyway, I am way past all this, and already gave my two cents on what should be done.

The application is for drag racing, excessive heat, the more metal the better, not the opposite way.
Just because its a company throwing facts does not mean anything, there are plenty of companies who give all kinds of promises in upgrades which we all know its just gimmicks.

Go ahead and install your lightened flywheel, balance it and enjoy the super duper performance on a two stroke... good luck with that.

Negative about slowing you down... this thread is boring.

 

[Jonny5]

Lmf

Either or, its a few pounds, not much of a difference... power to FL weight, the 4 cylinder is heavier.

Anyway, I am way past all this, and already gave my two cents on what should be done.

The application is for drag racing, excessive heat, the more metal the better, not the opposite way.
Just because its a company throwing facts does not mean anything, there are plenty of companies who give all kinds of promises in upgrades which we all know its just gimmicks.

Go ahead and install your lightened flywheel, balance it and enjoy the super duper performance on a two stroke... good luck with that.

Negative about slowing you down... this thread is boring.

I'm sorry but you are dumb..... if heavy flywheels are how to make your car fast than why do you see them for sale??? ATTENTION ALL RICERS IF YOU WANT TO MAKE YOUR CAR FAST JUST BOLT ON 2 FLYWHEELS TOGETHER TO DOUBLE THE WEIGHT. When is the last time you heard anyone brag that they put a heavier flywheel in their ride.

Ok.. so you tell me the last time you heard this. so ya man I upgraded my flywheel from 17 lbs to 65 lb one.

The only way a heavy fw will help is in an AWD car to help from stalling during launching.

Come on man think about it. It takes more power to move more weight. It don't matter where the weight is. Dead weight or rotational.

Every time you slow down and then go again. When you try to speed up you have to wait for it to get the extra weight back up to speed.
Who ever seeded you this garbage don't know what they are talking about. Do your self a favor and find a better mentor.

Or you can just continue to belive it and just make a steel insert like a very large washer to bolt on to your flywheel. Hell you can even start selling them. Make sure to sell one to whoever told you heavy fw are the shit.

 

[crankestein]

If you say so.
Not offended one bit.

You are missing by a ball park, and your thoughts are all over the place. You cant connect the dots and it clearly shows your lack of reasoning. Keep digging your own grave on this thread cause all its doing is making you look like a fool.

The reason you are here is because you need a mentor, and unfortunately its not going to be me. This last post you done has made the thread funny after all, and made me crack a few smiles which is a good thing.

 

[Jonny5]

If you say so.
Not offended one bit.

You are missing by a ball park, and your thoughts are all over the place. You cant connect the dots and it clearly shows your lack of reasoning. Keep digging your own grave on this thread cause all its doing is making you look like a fool.

The reason you are here is because you need a mentor, and unfortunately its not going to be me. This last post you done has made the thread funny after all, and made me crack a few smiles which is a good thing.

Lmao. If their were any truth in a heavier fw then why don't they sell them all over the place.

You are just a damn troll and you know you are wrong. Stop given shit info to people.

Maybe you should go to the drag strip and ask a bunch of racers "so what kind of extra heavy parts do they run" lmao

It's simple.. lighter parts = more hp. You need proof then bolt a Cobra fw to you 2 stroke and if your ideas are right you should have almost v8 power.

Good luck with your extra heavy racing flywheel.

 

[crankestein]

You cant connect the dots, oblivious of the subject in question.