Perrin light wieght pulley

[nikitopo]

So you accept that a car with a lighter pulley in reality revs faster, but you don't accept that it makes more power. This doesn't make sense. The engine is connected to the flywheel, to the driveshaft, to the wheels, to the road. You cannot have faster revs without more power. There is an imperfection in your logic.

All companies that sell such pulleys admit that the engine revs faster. Some of them provide also real dyno results, not the calculations the guys with the liquid pulley made in constant RPMs. We are not interested in such calculations, sorry. And these parts don't work just in race engines and race cars. It is like saying that an ordinary BRZ or an ordinaray STI weights lets say 3,000 pounds and a race version weights 1,000 pounds which is not the case.

It is your right to believe whatever you want, but you cannot mislead the readers or blame companies. I am the first to criticize companies if they sell irrelevant things or if their build quality is inferior. But we have to respect companies with big names and big history. Additionally, we should have a common understanding which parts are just for the looks like a fuel cap and which ones are for actual results.

Have a nice day gentlemen!

[churchx]

It perfectly makes sense. You don't make more power, but need to spend less energy to spin up parts when accelerating (or slow down, when braking). Once you get up to speed, power produced and spent is constant and same. It's acceleration and braking that changes to get there and back. But power produced & measured at wheels on dyno doesn't change, as you haven't changed any bearings to reduce friction loss, or on street also you haven't changed different tires with different rolling resistance or changed aero elements to change air drag.
I really don't get why you keep insisting on "my coffee is more hot", so "it should show on my hand watch". Unrelated things. As i tried to explain not just once, dyno tests do not measure/plot on chart what gets changed (acceleration/time to speed up). They measure and plot parameters that doesn't change (power/torque at rpms). Car accelerates faster and revs faster not because it produces more power, but because it needs to "deposit" less energy in "storage" of spinning up rotating items. Once that "storage is full" (car has reached specific speed/rotating parts reached specific rpms) only friction matters (it stays same) + on street air drag and tire rolling resistance (also stays same at steady speed). Engine. Does. Not. Makes. More. Power. With. Lightened. Pulleys. Even if you try to ignore arguments by others and laws of physics and call them illogical/not making sense.
P.S.
I'm in camp of preferring weight reduce on rotating items, as 'butt dyno' measures change change in acceleration, not actual power produced, and result will "feel" as if car is more powerful, hence i would prefer lightening weight there instead of removing weight elsewhere in car. But 1) i don't want to compromise car/transmission/engine longitivity in any way, 2) i'm cheap, hence prefering to gauge any upgrade from price/performance viewpoint. While lighter wheels/flywheel/brakes pass my requirements for cost/gains, lightened pulleys/axles do not.

[nikitopo]

If it is an issue of terminology, I can rephrase my previous comment:

You cannot have faster revs without more power.

into this one:

You cannot have faster revs without more speed.

Do we agree now that it works? Because all the others were saying that it is a useless modification

[nikitopo]

Originally Posted by churchx

Engine. Does. Not. Makes. More. Power. With. Lightened. Pulleys.

And please be more polite ..

I don't like this "word . word . word . " thing

[Wimpy]

Originally Posted by nikitopo

And please be more polite ..

I don't like this "word . word . word . " thing

I am beginning to think that the only troll in the room is nikitopo, what with ignoring facts, cherry picking items to which to reply, asking people to be more polite when they are simply clarifying their points, that kind of stuff.
Smells like the underside of a bridge in here.

[justatroll]

Originally Posted by nikitopo

So you accept that a car with a lighter pulley in reality revs faster, but you don't accept that it makes more power. This doesn't make sense.

Sorry, but it makes perfect sense if you understand physics.
Consider this diagram:



Force = Mass X Acceleration. or A = F/M

If you do an experiment with mass = 1kg and apply a force of 1 Newton, you get an acceleration of 1 m/s^2

If you reduce the mass to .7 kg but apply the same force you get more acceleration:

A = 1/0.7 = 1.42 m/s^2

So with the same force, the object accelerated more because it was lighter

So we can look at your statement again "So you accept that a car with a lighter pulley in reality revs faster, but you don't accept that it makes more power. This doesn't make sense."

I will break it down:
"So you accept that a car with a lighter pulley in reality revs faster" - Yes.
"but you don't accept that it makes more power" - No

However the rotating mass is less and the engine has exactly the same power so it will rev faster

Originally Posted by nikitopo

All companies that sell such pulleys admit that the engine revs faster. Some of them provide also real dyno results, not the calculations the guys with the liquid pulley made in constant RPMs. We are not interested in such calculations, sorry.

1 - "the guys with the liquid pulleys" did not provide calculations they provided dyno plots, real data.
2 - someone who is "not interested in calculation" is not interested in reality

Originally Posted by nikitopo

It is your right to believe whatever you want, but you cannot mislead the readers or blame companies.

Oh actually I CAN and I WILL point out inconsistencies with reality and false claims.
Or are the Mythbusters illegal vigilantes?

I could make the claim "you cannot ignore facts and physics" but you have proven that you indeed CAN if you so choose.

The biggest flaw in the reasoning on this topic that everyone refuses to accept is that: "A dyno does not measure the acceleration of the rotating mass"
A dyno measures the force the engine can exert at a constant RPM. PERIOD.
Once you can understand that you might figure out that at constant RPM the rotational inertia of the system means nothing.

Originally Posted by nikitopo

If it is an issue of terminology, I can rephrase my previous comment:

You cannot have faster revs without more power.

into this one:

You cannot have faster revs without more speed.

Do we agree now that it works? Because all the others were saying that it is a useless modification

No that does not work.
"You cannot have faster revs without more power"
Change that to:
"You can have faster revs with the same power and less mass"

I could not have been more polite in the above even though I was seriously tempted to insert snarky remarks (like something about knives and gunfights....).

I am now convinced that you are just trolling to see how much you can get me to type. Ok you win

[Simply_the_best]

Originally Posted by tofurun

I have read a lot of 2 sided posts everywhere about the pulleys. Most are old and on here around 2012/13 post. I'm just curious as of now what everyone's opinion on them and now that these cars have some miles have anyone had any problems. What exactly are people saying when they say they're acting as a damper and causing barring problems?

I'm a ASE certified technician. Engines fail all the time due to various conditions from improper oil on bearings, clogged oil filters, incorrect oil, low oil pressure, low oil level, detonation, the list can go on...there are also many people that run these FA20's (4U-GSE) hard on the track with no oil coolers; with temps upwards of 260+ degrees which is dangerous and quite frankly asking for engine failure. Even if it doesn't blow the engine in that very instance it still puts alot of wear on engine internals such as bearings. When oil is that temperature it is actually no longer lubricating parts properly. When the oil temps are up there it may be wearing away at some of the layers of the bearings with out any indications until days, months, or even years later when the engine spins a bearing or throws a rod because the bearing was worn out. Then everyone instantly points fingers to the lightweight crank pulley as the cause. People damage engine without them so its hard to point the finger at that. I have had the BuddyClub lightweight pulley set installed on my engine for roughly 27k miles with zero isssues. I drive my car harder than most on the daily, seeing redline at least once if not more every time I drive it. BuddyClub has been building cars and racing them for many years prior to the twins. To R&D something that would purposely blow engines would be dumb.
Specs on these pulleys:
Factory Crank = 4.89lbs
Buddy Club Crank = .88lb

Factory Water Pump = 1lb
Buddy Club Water Pump = .88 lb

Factory Alternator = .44lb
Buddy Club Alternator = .22 lb

Total Factory = 6.33lbs
Total Buddy Club = 1.98lbs

Hope this helps. Also I love my pulleys. I wouldn't drive this car without them. I don't plan on getting rid of them either.

[justatroll]

@Simply_the_best

Here is a good (technical) read on the harmonic damping abilities of the various pulleys:
http://www.ft86club.com/forums/showthread.php?t=85527

Yes it is from a vendor, so that has to be taken into consideration but the technical explanation passes my engineer's 'sniff test':

"To measure the effectiveness and impact of the heavier Fluidampr performance damper (5.8lbs, 3.8lbs rotating weight), a comparative test was developed against the stock tuned elastomer style harmonic balancer (4.87lbs) and a leading lightweight pulley (1.195lbs) that provided torque, horsepower and crankshaft torsional vibration comparisons. Two data set speed sweeps at a rate of 30 seconds each were conducted on each unit for consistency.
The torque and horsepower results proved positive on the chassis dyno with the Fluidampr performance damper besting both the stock damper and lightweight pulley, providing consistent performance gains from 4000rpm to redline. Despite the weight disadvantage, the results show that the optimum damping ability of the Fluidampr performance damper unleashed lost power through vibration control even with only mild performance modifications. Diving deeper to understand the cause of the power differences in the target rpm range between the lightweight pulley and the Fluidampr performance damper, a torsional vibration analysis was conducted. Using a high resolution laser and specialized measurement equipment the speed fluctuation or torsional vibration of the crankshaft can be recorded up to four trillion times a second (4THz, 4 pico-seconds). Results of the test reveal the rotating assembly’s resonance frequency, peak twist in degrees and how many vibration events occur during each revolution through the rpm range. The goal is to diminish torsional vibration as effectively as possible to create durability and efficiency. The results of the analysis depicted in the torsional vibration magnitude diagram below shows the sharp contrast between the protection provided by a Fluidampr performance damper and a lightweight pulley at the point when horsepower began to drop off for the pulley.
Further analysis shows that installing this lightweight pulley shifted the resonance frequency of the rotating assembly to a point directly within the rpm range. The result was higher magnitude 5th order and 6th order vibrations at a potentially destructive 600Hz from 4500rpm through redline. Higher frequency vibrations, because they happen more often per crank revolution can create hazardous stress, excessive wear and potential failure of bearings and oil pump gears. Under this test, the stress level felt by critical internal engine components increased three times with a leading lightweight pulley."

[Simply_the_best]

Originally Posted by justatroll

@Simply_the_best

Here is a good (technical) read on the harmonic damping abilities of the various pulleys:
http://www.ft86club.com/forums/showthread.php?t=85527

Yes it is from a vendor, so that has to be taken into consideration but the technical explanation passes my engineer's 'sniff test':

"To measure the effectiveness and impact of the heavier Fluidampr performance damper (5.8lbs, 3.8lbs rotating weight), a comparative test was developed against the stock tuned elastomer style harmonic balancer (4.87lbs) and a leading lightweight pulley (1.195lbs) that provided torque, horsepower and crankshaft torsional vibration comparisons. Two data set speed sweeps at a rate of 30 seconds each were conducted on each unit for consistency.
The torque and horsepower results proved positive on the chassis dyno with the Fluidampr performance damper besting both the stock damper and lightweight pulley, providing consistent performance gains from 4000rpm to redline. Despite the weight disadvantage, the results show that the optimum damping ability of the Fluidampr performance damper unleashed lost power through vibration control even with only mild performance modifications. Diving deeper to understand the cause of the power differences in the target rpm range between the lightweight pulley and the Fluidampr performance damper, a torsional vibration analysis was conducted. Using a high resolution laser and specialized measurement equipment the speed fluctuation or torsional vibration of the crankshaft can be recorded up to four trillion times a second (4THz, 4 pico-seconds). Results of the test reveal the rotating assembly’s resonance frequency, peak twist in degrees and how many vibration events occur during each revolution through the rpm range. The goal is to diminish torsional vibration as effectively as possible to create durability and efficiency. The results of the analysis depicted in the torsional vibration magnitude diagram below shows the sharp contrast between the protection provided by a Fluidampr performance damper and a lightweight pulley at the point when horsepower began to drop off for the pulley.
Further analysis shows that installing this lightweight pulley shifted the resonance frequency of the rotating assembly to a point directly within the rpm range. The result was higher magnitude 5th order and 6th order vibrations at a potentially destructive 600Hz from 4500rpm through redline. Higher frequency vibrations, because they happen more often per crank revolution can create hazardous stress, excessive wear and potential failure of bearings and oil pump gears. Under this test, the stress level felt by critical internal engine components increased three times with a leading lightweight pulley."

Guess we shall see exactly how destructive these vibrations are come 100k.

[OkieSnuffBox]

A case study does not a generalization make.

You can't make sweeping generalizations of performance, longevity, reliability, etc. Off a singular or very small sample size with any real accuracy.

[justatroll]

OT Warning - This post has absolutely zero information about crank pulleys.

Originally Posted by nikitopo

I am the first to criticize companies if they sell irrelevant things or if their build quality is inferior. But we have to respect companies with big names and big history.

"with big names and big history." - You mean like "Volkswagen"?

So using that logic, we should just "respect" diamond's "word" that these cables are superior?

http://www.audioquest.com/ethernet/diamond

Even when they make statements like this?:

"DIRECTIONALITY: All audio cables are directional. The correct direction is determined by listening to every batch of metal conductors used in every AudioQuest audio cable. Arrows are clearly marked on the connectors to ensure superior sound quality. For best results have the arrow pointing in the direction of the flow of music. For example, NAS to Router, Router to Network Player."

They just said that ethernet cables are directional with respect to audio quality.

So you dont believe that some vendors will say absolute lies to support their claims to get you to buy their product?
The fact that they provide this information on a webpage in a professional looking manner seems legit - when It is absolute hogwash!

If you believe that all vendors are pillars of truth then you live in a fantasy land.

[nikitopo]

Originally Posted by justatroll

Sorry, but it makes perfect sense if you understand physics.

I understand everything of what you are saying. I just don't like to use a technical language in a car forum.

Originally Posted by justatroll

Oh actually I CAN and I WILL point out inconsistencies with reality and false claims.
Or are the Mythbusters illegal vigilantes?

No, I like Mythbusters. Do you know why I like them? Because they always provide evidence. Do you want some evidence from my side?


Check here a BRZ with a racing clutch and a lightweight flywheel. The principle is exactly the same with the one of the pulley. The only difference is that you're removing more weight and you have more gains.


Check how the car is revving:
[ame="https://www.youtube.com/watch?v=yIrhH2yOmJY"]ORC Racing Concept レーシングコンセプト BRZ - YouTube[/ame]

Check now how it goes in a straight line together with a S2000 (at 7:03):
[ame="https://www.youtube.com/watch?v=ACs_3xLmuNg"]関西å³*最速戦 PRIDE â…§ S2000 vs 86 vs BRZ - YouTube[/ame]

Even in the whole race the difference is negligible.

The BRZ is N/A (no FI), has stock ECU and stock headers. What is changed is just the catback and the racing clutch and the flywheel. Overall difference is very small and cannot justified only by the catback gains. The S2000 is about 240 hp (JDM spec).

[nikitopo]

End of course in the end of the race the BRZ wins

[justatroll]

Originally Posted by nikitopo

End of course in the end of the race the BRZ wins

It is actually funny: I have a BRZ and my son has a S2000, but we have never been on the track together before.

However my 1971 mid engine 4-cyl boxer vintage racecar can likely beat both of them.