natecivic92

I am going to use a comp clutch stage 4 for my set-up since I am going to make hp in the 500range should I stay with a stock flywheel or would it be better to go with a lighter aftermarket one 10lbs or so?The engine is a Ls b18b1 built.With a ls tranny.

cjordan

iTrader: (1)

I do not know what the majority runs, but I have a GT35R powered 2000 Si and I am running a Unorthodox Racing Flywheel ( 8 lbs. ) I have been very happy with it.

2point2

ACT prolite flywheels are chromoly if that makes you feel better. I can't see any issues with running high hp apps with it.

turbotypeR@SPEC

you will like a heavy flywheel better on a turbo honda. the light weight one will allow the engine rpm to bogg more, especially between shifts than the heavy one. use the stock one. you will be glad you did

Schister66

On a higher horserpower application, you're going to want something a little heavier. Granted, it may take a hair longer to rev up, but you're going to have more kinetic energy when your car gets into those high RPMs. Also, when you shift, you wont fall out of boost as easily with a heavier flywheel. I would say that an 11lb would be THE LIGHTEST i would go.

agrn93ls

500+ hp LS?

96 GSR-T

I run an ACT Streetlite and I am happy with it.

quicksilver1689

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by agrn93ls &raquo;</TD></TR><TR><TD CLASS="quote">500+ hp LS?</TD></TR></TABLE>
why not? headwork and 404's?

b16a4

i went from my 7lbs fidanza back to stock.

PHDZINE

As you can see...anything will work. Personally I run the lightest flywheel that I can find.

agrn93ls

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by quicksilver1689 &raquo;</TD></TR><TR><TD CLASS="quote">
why not? headwork and 404's? </TD></TR></TABLE>

yeah, its just rare to see that, kinda.

just would seem cheaper easier to ls/vtec

urbansi

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">On a higher horserpower application, you're going to want something a little heavier. Granted, it may take a hair longer to rev up, but you're going to have more kinetic energy when your car gets into those high RPMs. Also, when you shift, you wont fall out of boost as easily with a heavier flywheel. I would say that an 11lb would be THE LIGHTEST i would go.</TD></TR></TABLE>

See i have had this discussion with some old school people and its something that is worth discussing. If you are trying to get the most out of a setup, a lighter flywheel is a great way to take some rotating mass away hence equaling power increase. I understand the whole falling out of boost issue, but i have been in a few big HP small displacement motor'd cars that had lightened flywheels, and your going to fall out of boost no matter what with a decent size turbo, expecially with a Honda. **** the only reason i dont like my light flywheel(8lb fidanza) is because its a little bit of a bitch to DD. I guess i was spoiled with my stocker and exedy for two years.

HYREV2NR

This has been a debate that still doesn't make much since to me.

So Danny, you are using the stock F/W on the Civic?

BTW, shouldn't you be working?

HYREV2NR

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b16a4 &raquo;</TD></TR><TR><TD CLASS="quote">i went from my 7lbs fidanza back to stock.
</TD></TR></TABLE>Elaborate please.

bigbadboy

if your afraid of falling out of boost during the shifts then keep your foot to the floor and/or set up some kind of WOT shift like on hondata and there problem solved.

Schister66

Overall HP numbers and falling out of boost aside...think about this: If you have a lighter rotating mass, it has less kinetic energy. If you have a heavier rotating mass, you have more kinetic energy. During a high load situation (i.e. full throttle) the more rotating mass one has, the more potential energy available when needed.

The way i think about it visually is this: If you're rolling 2 objects at someone, which would be easier to stop (provided friction is equal). A 3' diameter beach ball filled with air or a 3' diameter solid steel ball bearing? The beach ball is able to get up to speed quickly (via force provided by person pushing it); similarly, it will come to a rest more quickly when opposite force is imparted on it by the person trying to stop it. The ball bearing takes more energy to get moving, but once it is moving, it doesn't want to stop for anything (per Newton's First law of Inertia).

This same thought process can be used when thinking about flywheels. Granted, may not make as much power or rev as fast, but the power is going to be more static through the powerband because load will not affect the engine's performane as much AND since there is more load at lower RPM, the turbo should spool faster. Diesel's run very heavy flywheels so that excess load does not stall the engine out as easily. The engine effectively "stores" potential energy in the flywheel (and rotating assembly).

Thoughts?

top end tuner

wow i never thought of it that way but what if you want something in between. something that would just pickup a little better but also be able to transfer a good amount of load?

Schister66

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by top end tuner &raquo;</TD></TR><TR><TD CLASS="quote">wow i never thought of it that way but what if you want something in between. something that would just pickup a little better but also be able to transfer a good amount of load?</TD></TR></TABLE>

This is why i personally suggest a flywheel between the 9-13lb range. I use an 11lb on my DD

beepy

The weight of the flywheel has nothing to do with the power the engine can produce. It doesn't even affect parasitic loss. All of the energy that the engine produces is recovered. A flywheel is a capacitor for your engine; it stores energy that the engine needs during its power lapse, thereby smoothing out vibrations and oscillations. Sure, the power that would have been stored in a heavy flywheel goes to the wheels instead if you don't have that flywheel to spin, so you notice a seat-of-the-pants power increase. But, IMHO, unless your car is a trailer queen, the benefits are outweighed by the problems inherent in a 4-cylinder engine without a proper flywheel, ie, more rotating assembly vibration, more likely crank and bearing damage, and the fact that the engine revs down very quickly.

Schister66

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy &raquo;</TD></TR><TR><TD CLASS="quote">capacitor</TD></TR></TABLE>

That's the word i couldnt think of...its probably the best way of describing what a properly sized flywheel does.

TheShodan

iTrader: (14)

Here's something I wrote eariler when one asked the same question.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TheShodan &raquo;</TD></TR><TR><TD CLASS="quote">The lighter flywheel purpose is 2 fold. It's not necessarily a Better/Worse ideology, more of a is-it-better-for-my-purposes thinking.

The amount of POWER has nothing to do with it in the long run. The POWERBAND is what changes with a lightened flywheel. When it comes to using a turbocharger, the benefit (or detriment) really comes with the turbocharger used, and how your driving style is. Yes, Lighter flywheels remove a lot of rotational inertia off of the rotating assembly, but there's a bit more to it than just a "weight saving" aspect.

When it comes to most of our smaller displacement engines, (under 2.0 litres), the peak hp that a car makes is really going to be in the upper rpm range, about the last 3K rpms, in which, unless you plan on driving that hard on a street on a daily basis, really isn't the point of POWER that you should look at. Instead, you need to focus on the entire range of power that you plan to make. Lighter flywheels can be a hinderance if your purpose is to not shift as often, and keep the power at a lower part of the band, which is the 3000-7000 range on most VTEC engines (this number generally is different with different engine applications, so this is simply an example.)
When you have a lighter flywheel, that is normally for NA applications, peak torque and power are in the upper band, and each faster shift that is made with the lighter flywheel keeps the rpms right at the rpm range to keep peak power and torque. The drawback for some people is that if you don't shift fast enough, the engine drops down faster OUTSIDE of the powerband, and you feel slower.

How does this affect turbocharged applications? It means that if the turbo car is outside of its powerband, the same thing happens. If the turbo is large, this means that it will take longer for the turbo to recover spool characteristics effectively. (For hondas, anything larger than a 60 trim, could POSSIBLY result in slower response, but that depends upon static and effective compression, displacement, final drive etc). Smaller turbochargers give a bit more torque than power, so imagine the result of something like a larger displacement NA motor. The lighter the flywheel, the faster it will fall out of its band if you don't shift fast enough. That being said, 8lb flywheels aren't that ideal, but 12lb ones, or stock for VTEC engines are just fine.


I personally went with a slightly lighter flywheel for my turbo road-race application. Some LS owners like to uses slightly lighter flywheels, especially if they use really efficient turbochargers with headwork. Most VTEC engines don't need it. Stock will work.


Modified by TheShodan at 6:44 PM 11/7/2007</TD></TR></TABLE>

turbotypeR@SPEC

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by HYREV2NR &raquo;</TD></TR><TR><TD CLASS="quote">This has been a debate that still doesn't make much since to me.

So Danny, you are using the stock F/W on the Civic?

BTW, shouldn't you be working? </TD></TR></TABLE>
i am using the SPEC steel flywheel that comes on our twin disc.
BTW- this is work for me.lol

rorik

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Schister66 &raquo;</TD></TR><TR><TD CLASS="quote">During a high load situation (i.e. full throttle) the more rotating mass one has, the more potential energy available when needed.
Thoughts?</TD></TR></TABLE>
Only way to extract the energy is by decelerating the mass. Any time the rotating mass is being accelerated, it is absorbing energy. What is your motor doing when you're at full throttle? (for a given gear) Accelerating. So your statement is actually completely the opposite of what would happen, until you shift. Then the flywheel's energy is mostly wasted as the tires spin..

I'm not exactly sure what you mean by a "high load situation", but it's just a confusing way of looking at it, in my opinion. Loading is irrelevant to the amount of potential energy available. The flywheel will always add or take the same amount of energy for the same amount of decrease/increase in rotational velocity.

With a torsionally unbalanced motor with firing impulse so far apart, an ultra light flywheel is not something I would use. Neither is a really heavy one though. I like my act streetlite 12lb unit.

agrn93ls

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy &raquo;</TD></TR><TR><TD CLASS="quote">The weight of the flywheel has nothing to do with the power the engine can produce. It doesn't even affect parasitic loss. All of the energy that the engine produces is recovered. A flywheel is a capacitor for your engine; it stores energy that the engine needs during its power lapse, thereby smoothing out vibrations and oscillations. Sure, the power that would have been stored in a heavy flywheel goes to the wheels instead if you don't have that flywheel to spin, so you notice a seat-of-the-pants power increase. But, IMHO, unless your car is a trailer queen, the benefits are outweighed by the problems inherent in a 4-cylinder engine without a proper flywheel, ie, more rotating assembly vibration, more likely crank and bearing damage, and the fact that the engine revs down very quickly.</TD></TR></TABLE>


enough reason not to do it. minimal gains for a highly likely negative outcome

rorik

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by beepy &raquo;</TD></TR><TR><TD CLASS="quote"> A flywheel is a capacitor for your engine</TD></TR></TABLE>

This is a very good analogy. A really large capacitor isn't what you want when you're trying to increase the voltage quickly though, and when you have to discharge it through a circuit that is inefficient at high loads (tirespin)

I think it is universally accepted that all oem flywheels are on the heavy side..