is better for sand dunes use the 12.5 lbs flywheel??

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pablo3969
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is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

Hi Again, for my sandrail with vw 2187cc (Scat 78,8 volksracer forged crank) and C25 cam,8,5 cr....wich is better for solid low end and torque and only sand dunes use!!.....: lightened flywheel or stock weight????.......thanks.

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r erfert
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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by r erfert »

A lightened flywheel will let you rev up faster.
With your bigger motor you should have plenty of HP to push a stock flywheel.

That being said I run a lightened flywheel in all the my cars just to reduce the rotating mass and it makes more HP at the wheel.

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

ok....but in my specific case and dunes climbing.....lightened or stock weight flywheel??? thanks.

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by r erfert »

pablo3969 wrote:ok....but in my specific case and dunes climbing.....lightened or stock weight flywheel??? thanks.
So exactly what part of
A lightened flywheel will let you rev up faster.
With your bigger motor you should have plenty of HP to push a stock flywheel.
That being said I run a lightened flywheel in all the my cars just to reduce the rotating mass and it makes more HP at the wheel.
Did you not comprehend :?:

How heavy is your rail with people in it?
I think your sandrail with vw 2187cc will be fine with either flywheel.....If you have the money and want to swap to a lightened flywheel (refer to quote) it will rev faster and have less rotating mas when you are on the gas and going up hills.....This is a plus less rotating mas = more HP. :D

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

then,i preffer lightened flywheel!!! thanks.

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by Mark@STU »

Pablo

Just two cents here, and based on having many years of observing how flywheel weight affects vehicles of all types that race and play in the sand. Also keep in mind this is just my opinion.

First and foremost we must agree on what a flywheel is, before we discuss why we should run one over another. In my opinion, I see a flywheel as a mechanical battery, that being something that stores energy. If that is in fact what a flywheel does then we need to approach the discussion of why we might want a heavy (i.e. stock weight) vs a light flywheel.

Here are a couple of examples from years and years of watching how flywheel weight can be critical to performance in the sand. I would like to make mention here that there is clearly an application for light flywheels in different motorsports i.e boats etc.

My first education about flywheel weight was as result of a AA Jeep sand drag vehicle owned by Cary Stanley, that STU sponsored running an aluminum flywheel and aluminum pressure plate behind a supercharged de-stroked small block 400. This thing weighed about 1200 lbs., and not sure on the HP but was extremely fast. Motor was fresh, 20.00-15 just came out around 1977, first time with the aluminum flywheel and on the first run the motor laid down at the line. Once he went back to the stock steel flywheel and pressure plate it left the line unbelievably hard and picked up several tenths in the 100 yards. I believe this happened because he was able to store the energy from the engine in the flywheel and once he pulled the trigger that stored energy carried him through to allow the motor to get in to it’s power band.

Over the years I’ve had numerous customers with what they believed to be tires too aggressive for their sand cars. When in fact they found when they switched back to a stock weight flywheel the problem completely went away. When I get a call from someone having this symptom my first question is what weight flywheel are they running and overwhelmingly their running a light flywheel.
We can talk about motor size, HP, torque, blowers, turbo’s etc. and how flywheel weight affects all of them differently. However, the one common denominator is sand and how we shock-load tires in ways we typically don’t do in other forms of motorsports.

So, in a nutshell this is what I suggest to people when it comes to our sand “stress-management equipment”, flywheel weight and tire and wheel weight. Go as heavy as possible in the area of flywheel and pressure plate weight and reduce as much weight as possible from the tire and wheel assembly and call me in the morning.

Ok, it was three cents :roll:

mark@stu

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

Mark@STU wrote:Pablo

Just two cents here, and based on having many years of observing how flywheel weight affects vehicles of all types that race and play in the sand. Also keep in mind this is just my opinion.

First and foremost we must agree on what a flywheel is, before we discuss why we should run one over another. In my opinion, I see a flywheel as a mechanical battery, that being something that stores energy. If that is in fact what a flywheel does then we need to approach the discussion of why we might want a heavy (i.e. stock weight) vs a light flywheel.

Here are a couple of examples from years and years of watching how flywheel weight can be critical to performance in the sand. I would like to make mention here that there is clearly an application for light flywheels in different motorsports i.e boats etc.

My first education about flywheel weight was as result of a AA Jeep sand drag vehicle owned by Cary Stanley, that STU sponsored running an aluminum flywheel and aluminum pressure plate behind a supercharged de-stroked small block 400. This thing weighed about 1200 lbs., and not sure on the HP but was extremely fast. Motor was fresh, 20.00-15 just came out around 1977, first time with the aluminum flywheel and on the first run the motor laid down at the line. Once he went back to the stock steel flywheel and pressure plate it left the line unbelievably hard and picked up several tenths in the 100 yards. I believe this happened because he was able to store the energy from the engine in the flywheel and once he pulled the trigger that stored energy carried him through to allow the motor to get in to it’s power band.

Over the years I’ve had numerous customers with what they believed to be tires too aggressive for their sand cars. When in fact they found when they switched back to a stock weight flywheel the problem completely went away. When I get a call from someone having this symptom my first question is what weight flywheel are they running and overwhelmingly their running a light flywheel.
We can talk about motor size, HP, torque, blowers, turbo’s etc. and how flywheel weight affects all of them differently. However, the one common denominator is sand and how we shock-load tires in ways we typically don’t do in other forms of motorsports.

So, in a nutshell this is what I suggest to people when it comes to our sand “stress-management equipment”, flywheel weight and tire and wheel weight. Go as heavy as possible in the area of flywheel and pressure plate weight and reduce as much weight as possible from the tire and wheel assembly and call me in the morning.

Ok, it was three cents :roll:

mark@stu
ok. Mark...... very clear and confiable opinion!!! but, i dont understand the much different experience opinions with respect to theme!!!........50% lightened and 50% stock weight flywheel!!......now, considering solid low end and torque sand use.... my inclination is for stock weight in my 2187cc!!! thanks.

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by Mark@STU »

Paplo,

“i dont understand the much different experience opinions with respect to theme!!!”
pablo3969

Isn’t that why you asked your question, you wanting different opinions?
From here you have more information than you started with albeit possibly confusing. Valuable with respect to your inquiry, that would be your call.

mark@stu

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

Mark@STU wrote:Paplo,

“i dont understand the much different experience opinions with respect to theme!!!”
pablo3969

Isn’t that why you asked your question, you wanting different opinions?
From here you have more information than you started with albeit possibly confusing. Valuable with respect to your inquiry, that would be your call.

mark@stu
exactly....in my case and for sand dunes,my inclination is for kinetic energy!!!

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by FE135 »

I'll try to keep my opinion simple. In my VW powered cars, the lighter flywheel was better. You might want to also consider the stroker cranks are a little heavier than stock so why add weight to your motor. Heavier launches better - lighter revs faster.

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by pablo3969 »

yes...but the question is for sand dunes use!!

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Re: is better for sand dunes use the 12.5 lbs flywheel??

Post by FE135 »

pablo3969 wrote:yes...but the question is for sand dunes use!!
Yes, is there any other type of use?

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