got the Unorthodox Racing pulley!

White_Hair said:
Thanks for the correction EG. I was base on the fact how bicycle works. Same amount of work with smaller gear, you will need more revolution to get to the same distance. Sorry I am not a mechanical guy. :.smile:
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You actually said it right. If the crank pulley is underdriven (smaller), it'll cause more revolutions on the alternator pulley (since they're connected with a belt). It generates more heat & wear on the alternator and the extra energy it generates are not used. It's just three separate cases and you explained the third one :smile:

Now that I'm thinking of it, technically speaking, just using the crank pulley may be a better solution for people using aftermarket audio systems?? Dee, maybe you won't need that second battery at all?? :hmmmm:
 
EG3 said:
You actually said it right. If the crank pulley is underdriven (smaller), it'll cause more revolutions on the alternator pulley (since they're connected with a belt). It generates more heat & wear on the alternator and the extra energy it generates are not used. It's just three separate cases and you explained the third one :smile:

Now that I'm thinking of it, technically speaking, just using the crank pulley may be a better solution for people using aftermarket audio systems?? Dee, maybe you won't need that second battery at all?? :hmmmm:
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The mechanic wear is usually not as a big problem for the alternator. The alternator is designed for running at with high rpm. The problem is the heat. The higher heat will cause the magnets to start losing the magnetivity of and also creating wear on the coil insulation or coating. That is why the dealership performs the resistance test for your car alternator to verify if the alternator is in good shape or not.

I think it will be better to have a second battery for high power aftermarket audio. Most like just for the fact your car battery may not keep up with the demand of the extra load and the alternator can only charge the battery at a certain range of current. Then your battery will be bad really soon with a bad cell due to over draining.

I am not professional, but just some information sharing. Please correct me if I am wrong.

Now I am trying to do more reading like you do, EG. :tongue:
 
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what i can tell you guys, that at the moment i do not feel any disadvantage to change to underdrive pulley.

is work great and smoothly
EG3 said:
I believe if you reduce the alternator pulley size, it'd lower the alternator rpm thus increasing its load. The weight savings factor would be insignificant compared to the lost rpms I believe.. If you think that alternator is one huge generator, it's electricity generating capacity is dependent on it's size and it's revolutions per minute..

---------- Post added at 04:11 PM ---------- Previous post was at 04:08 PM ----------



beat me to it :smile:



With smaller alternator pulley size, the alternator runs slower. Using smaller crank pulley AND alternator pulley together, it helps to get rid of the rpm difference. With just a crank pulley, there's no extra load on alternator but it wears faster and might cause headlight glare in some situations (not us).

---------- Post added at 04:13 PM ---------- Previous post was at 04:11 PM ----------

Simply it's best if you use the whole pulley set OR just the crank pulley. Either way, the majority of the power gains will come from the crank pulley, which is sensitive to weight savings, not the accessory pulleys.
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Not saying you will have the problem right away. And depending on how you drive your FX. The alternator life may be shorten from 10 years to 8 years. It is just somehow luck dependent. But no doubt with the light weight pulley, you will definitely feel the difference in performance.
 
EG3 said:
You actually said it right. If the crank pulley is underdriven (smaller), it'll cause more revolutions on the alternator pulley (since they're connected with a belt). It generates more heat & wear on the alternator and the extra energy it generates are not used. It's just three separate cases and you explained the third one :smile:

Now that I'm thinking of it, technically speaking, just using the crank pulley may be a better solution for people using aftermarket audio systems?? Dee, maybe you won't need that second battery at all?? :hmmmm:
Click to expand...

Only the crank uses a smaller, underdriven pulley. The alternator pulley size is stock - even in the underdrive pulley set.

Again, I think you guys have it backwards. A smaller crank pulley (underdriven) used with a stock sized alternator pulley will spin the alternator SLOWER, not faster. Think about it. Gearing: One rotation of a smaller wheel does not go as far as one rotation of a larger wheel. But it takes the same amount of time to make one revolution for each. Think RPMs. So the belt is only moving 80% of the distance underdriven. That is why it is called "Under-driven". Because the belt is being driven "under" stock speeds, thus reducing the demand on the crank, allowing that efficiency to be transferred to the wheels.

Also, the alternator DOES provide power to the system as it is working - via the battery. If you disconnected your alternator, there isn't enough juice in the battery to keep the systems going. The battery is used to store and regulate the voltage, but without the alternator it won't work the electrical systems. So with an underdriven pulley, there is a risk that you won't have a fully charged battery with high electrical demands. But I think we are hearing from everybody on the site that they have not noticed any side effects. Good sign!
 
Does anybody know why the pulley sets only come with three pulleys, but we have 6 down there that can be replaced? Why not all of them? Sup with that?
 
that not true, if you go to stillen, they offer difference kit. the main pulley is the crank pulley, the only that will give you extra gain performance, the other pulley are just for luxury.

http://www.stillen.com/product_files/400337~photo.1.jpg

right now i have the underdrive undernox pulley, is very similar to this one, stillen offer it in the beginning before start the production of this one.

jumbosrule said:
Does anybody know why the pulley sets only come with three pulleys, but we have 6 down there that can be replaced? Why not all of them? Sup with that?
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jumbo is correct, a smaller crank pulley will reduce the rpm's of all belt driven accessories. the 2 places it can be most noticeable is in the charging system & the a/c system. some cars will start to dim lights & such at idle, & some cars may start to blow less cool at idle with an under driven crank pulley.

as far as weather the car is running on the alternator or the battery when running, this is a tricky question & can cause way too much typing for me at the moment to give a complete answer :tongue: the simple answer is the car is running on the battery but the battery is being supported by the alternator so really it's technically running on both as a system.

the battery is a storage unit. if your audio system is drawing on average higher that the average output of the alternator then the only thing that increasing to 2 batteries will do is extend the amount of time before depletion. this can help in some situations but is not necessarily a cure for the real problem, more like a band-aid. the alternator may get some relief at the highest load times because the system has a higher reserve, but then the alternator will also have to work twice as hard to replenish the 2 batteries...
 
turbocad6 said:
jumbo is correct, a smaller crank pulley will reduce the rpm's of all belt driven accessories. the 2 places it can be most noticeable is in the charging system & the a/c system. some cars will start to dim lights & such at idle, & some cars may start to blow less cool at idle with an under driven crank pulley.

as far as weather the car is running on the alternator or the battery when running, this is a tricky question & can cause way too much typing for me at the moment to give a complete answer :tongue: the simple answer is the car is running on the battery but the battery is being supported by the alternator so really it's technically running on both as a system.

the battery is a storage unit. if your audio system is drawing on average higher that the average output of the alternator then the only thing that increasing to 2 batteries will do is extend the amount of time before depletion. this can help in some situations but is not necessarily a cure for the real problem, more like a band-aid. the alternator may get some relief at the highest load times because the system has a higher reserve, but then the alternator will also have to work twice as hard to replenish the 2 batteries...
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Thanks for the info Turbo. :.smile:
 
Hey Fellas just catching up on the reading and it al sounds good to me. Alittle off topic, but here is the thing I have experienced in the past, with high wattage/amp systems. IMO, as long as you had no preivous problems with alternator, battery, and had good wiring and ground points you should minimize most issues revolving around the stereo electrical system. So I've hoped anyway. For example in the past I'v used capacitors , in conjunction with standard powered systems, and in the long run had to replace batteries, and or altenators for one reason or another, that another thread. But when I ran dual battery system I never seem to have any of these issues. and over the years learning that if I recondition my batteries every so often I've extended the life of the battery and have yet to have an issue with my alternator.

So now if having an under driven pulley reduces some load then great. now I haven't run my A/C yet. So I can't really make any comments as to what effects I'll get in the future. I don't play my system loud, on occassions though I do. Over the last few weeks, I've had to tone down the decibles of the bass, at a level I can enjoy. Mined you I haven't messed with any tuning. so as far as that I can't explain, with the exception of current recording I've added it always apossibility which can come into play. Also another thread....

As far as the under-driven pulley goes it is a great MOD for me thus far, no complaints. like everyone here that has done this MOD or the stock size pulley it a great addition to the VQ engine. unless if you are plan on doing something like FI this is nice to have.
 
Deecarp said:
Hey Fellas just catching up on the reading and it al sounds good to me. Alittle off topic, but here is the thing I have experienced in the past, with high wattage/amp systems. IMO, as long as you had no preivous problems with alternator, battery, and had good wiring and ground points you should minimize most issues revolving around the stereo electrical system. So I've hoped anyway. For example in the past I'v used capacitors , in conjunction with standard powered systems, and in the long run had to replace batteries, and or altenators for one reason or another, that another thread. But when I ran dual battery system I never seem to have any of these issues. and over the years learning that if I recondition my batteries every so often I've extended the life of the battery and have yet to have an issue with my alternator.

So now if having an under driven pulley reduces some load then great. now I haven't run my A/C yet. So I can't really make any comments as to what effects I'll get in the future. I don't play my system loud, on occassions though I do. Over the last few weeks, I've had to tone down the decibles of the bass, at a level I can enjoy. Mined you I haven't messed with any tuning. so as far as that I can't explain, with the exception of current recording I've added it always apossibility which can come into play. Also another thread....

As far as the under-driven pulley goes it is a great MOD for me thus far, no complaints. like everyone here that has done this MOD or the stock size pulley it a great addition to the VQ engine. unless if you are plan on doing something like FI this is nice to have.
Click to expand...


How about an update Dee...

Im still holding on to my underdriven pulley... just dont want the wife to complain about the lack of AC. :)
Im planning on doing it anyways...

---------- Post added at 03:29 PM ---------- Previous post was at 01:34 PM ----------

OK,

I had some time today and took it to the mechanic.
had it installed in less than 30 mins.
I haven't reset the ECU yet, but initial feeling was like others have mentioned... quicker rev up.

I will also post future review once the hot SoCal summer kicks in.
 
Deecarp said:
As far as the under-driven pulley goes it is a great MOD for me thus far, no complaints. like everyone here that has done this MOD or the stock size pulley it a great addition to the VQ engine. unless if you are plan on doing something like FI this is nice to have.
Click to expand...

When you say ...unless FI..., you are talking about a supercharger, correct? For a turbo application, the underdrive pulley would still be beneficial, right?

And again, can you buy more than just the three pulleys for the VQ? What about the other three? There are six on the engine. If I wanted to replace them all with a polished stock size pulleys, are there any options out there?
 
there are only 3. the other ones are for belt tension.
might be ok for turbo ,def not ok for supercharge (SC uses the belts to drive the unit)
edit: they offer a stock diameter on that they claim will work with SC.


* one thing I have noticed is the "lag" when you first step on the pedal is very minimal now w/ the pulley
 
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