mattvs

If you're a beginner on a 5-speed, any 'speed' modifications will make the car more challenging to drive. The more power you're putting down, the tougher it is to get the car moving without either stalling or taking off like a bat out of hell...and balancing that with not roasting your clutch.

I'd recommend 5-speed newbies (no mockery intended) to keep modifications to audio/visual until fully comfortable with the car's power as it is stock, and fully confident in your ability to handle shifting in all situations, be it rain, snow, steep friggin hills, etc.

Hell, I've been driving stick since I was a sophomore in high school and I haven't modded the Evo yet because I'm still getting used to the increased power over the tC. :p

engifineer

A lightweight flywheel has the same performance effect as a lightweight pulley, only its effects are much more noticeable because you are removing mass from a larger diameter. The other difference is that you are not removing the damper, so you do not decrease engine life (removing the damper WILL decrease engine life to some degree.. that degree depends on engine, use, driver, etc).

The flywheel will make launching a bit harder since the engine carries less momentum (this feeds back to why you are not "freeing up horsepower") as you decrease rotating mass. So you will need to launch higher and harder to get the same result. This is why if all I cared about was 1/4 mile racing, I wouldnt bother with a lighter flywheel as quickly. The improved launch with the heavier unit can be an advantage off the line.

So I wouldnt say more difficult, but it will change the way you drive the car. Depending on what you have driven before and how used to the tC you are, it could make it harder or easier.

NightShade

I think I will save my money and use it for bolt ons that are not intergrated into the engine or things like that. So now, I hope to sell my Tsudo N1 system for a tanabe concept g and a injen cai. Thanks people for your input, but I think its safe to say that Im not a racer, and if its only a little hp if any its not worth the risk or money to put it on myself or get it done. So Thanks,

kurt26

So why doesn't any aftermarket company make a pulley with a damper?

soros151

Not cost effective, since the damper piece cost a lot more. Aftermarket pulleys with dampers surpass the $325 mark.

kungpaosamuraiii

ATI makes a dampened pulley; only, it weighs more than stock to deal with the excess power in Leslie Durst's tC. No dice there.

A lot of people were interested at YStC but there aren't enough people there to get them to make a lightened pulley. I wonder how many people here would want one from ATI or Fluiddampr? Somehow, I imagine most people here would want the NST or ZPI pulley.

soros151

those are the ones that cost over $300 bucks.

hPower

This topic has been beaten to death so many times its not even funny. Talk to Mike from NST online and he will tell you that they are very capable of building crank pulleys with a damper. There are two reasons why the do not.

1. The cost of building such a pulley would push the retail price over $300 and people do not like paying such prices. How long would it take them to sell 100 pulleys of such design? People cry and complain that "we want this and we want that, but when the time comes to open their wallets they run and hide!"

2. According to their experience with pulleys over the years, they have seen enough first hand pulley use to conclude that such a piece is not absolutely necessary.

How many people do we have on SL using solid pulleys of various types who have had engine failure? How many people do we have using solid pulleys who have strong running engines? I think we have a thread covering those stats somewhere

soros151

Yep, it is stated on the first page, the thread I mean.

WhitetC21

So.....the flywheel and pulley do free up horsepower, especially with other bolt ons header, exhaust, etc?

mattvs

If I had a rubber tube I would beat you with it. Read the thread for god's sake.

WhitetC21

Rubber tube? I don't swing that way bro....

I wanted inputs from more people, I don't take something for fact cause a few ppl said so

hPower

The more mods you have, or the more power you start with, the better your gains and throttle response will be after a pulley kit or flywheel installation.

Start with 100 horsepower and you will see a little bit of gain, start with 300 horsepower and you will see a little bit more gain in response and performance. This is why turbo charged cars usually see better performance gains with basic bolt ons.

engifineer

Well, if you want to find something you can take for fact regarding whether reducing rotational mass increases the amount of HP the system outputs, then you can find yourself a book on basic mechanical phyics. Read all you can on the laws of motion first. Then read about rotational motion and how the principles relate between the two types of motion and you will have some good fact regarding why you havent freed up any power.

If you reduce it enough, will you have noticeable effects on accelleration? It depends on the load on the system. Revving in neutral will be more effected than revving in gear while pulling the car, and both effects depend on the amount of mass removed and the diameter it is removed from.

So you have affected rotational acceleration, but not power output.

Then, look here:

http://www.germanmotorcars.com/Dyno_...0inertia_1.htm

to see why inertial dyno numbers can be inaccurately affected by rotational mass changes. That article will put the rest of the info above into perspective and will serve as some good reading nonetheless.

EATUMM11

i like

EATUMM11

i know a bunch of people with them and they also like z

rhythmnsmoke

For those of you beating on the "a pulley does not make power", "nor does it free up power", what is your educated explanation for such dyno graph pictured below.

Before pulley 134.4whp 145wtq
After ZPI vr.2 Crank Pulley 146whp 163wtq

That's a gain of 11.6whp and 18wtq. Is this considered "GHOST" hp and tq?

zer0

http://clubstlscion.com/forum/forum_...835&PN=1&TPN=3

soros151

Awsome. Thanks!

engifineer

You do realize that measuring hp with varying rotating inertias on an inertial dyno (or anything other than steady state measurements on any system) is going to give you incorrect gain numbers dont you? That is the whole point made if you look at the physics behind them. If you slap lighter wheels and tires on a car between non-steady state, or inertial dyno pulls you will also erroneously read and increase in whp. The same goes for wheels, or any rotating objects. Observing all laws of rotational motion, a heavier wheel is no harder to keep spinning than a lighter one. Actually ,the heavier wheel becomes an advantage the minute you reach a steady state. The only effect at all is in accelleration (both positive and negative) of the wheel itself. It takes more energry to accellerate, but also takes less to keep it spinning. So although acceleration of the crank is made easier, it carries less momentum.

If someone can come out and dispell the laws of motion that we use everyday to calculate everything from automotive physics to the motions of the planets, then I will be all ears. And if one person can take a good number of 1/4 mile runs with a stock pulley, swap to a lighter one and take a good number more and show me a significantly (respectively) lower time, I may look closer. Will reducing mass help? Sure, since you are making acceleration of the engine easier, but I can bet that you will find that the real performance increase you measure on the track (especially with such a small change in rotational mass on a small diameter object) will not add up to a 15whp or so gain.

Anyway, as usual we are all beating this to death, and the people that believe anything a shop with a dyno and a part to sell will believe that, the people that want to believe one way or the other will believe the same and those of us that are a little more skeptical after seeing mod after mod produce little or none of what is promised (not suprisingly when the physics says it wont) will believe what we do. So I guess we can at least agree on that point and go to bed now.... :D