pulley Q
#2
I eat plastic.
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Underdrive pullies won't give you a magical 10hp. They take some effort off of the engine driving the accessories. It could have negative effects on the alternator though. I wouldn't really waste your money on it unless your car is supercharged.
edit: My friend says that you have to be careful with the electrical accessories because with your alternator not producing as much power, you can drain the battery quickly. This tends to be more of a problem on Japanese cars where the electrical systems are marginal as far as power goes.
edit: My friend says that you have to be careful with the electrical accessories because with your alternator not producing as much power, you can drain the battery quickly. This tends to be more of a problem on Japanese cars where the electrical systems are marginal as far as power goes.
#5
for a daily driver a lightened pulley does little and lowers the life expenctancy of the engine...most crank pulley's are harmonic balanced to the flywheel through the crank
the advantage they have is freeing up hp and engine response lost turning the heavier pulley
the advantage they have is freeing up hp and engine response lost turning the heavier pulley
#6
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well if its harmonicly balance with the crank wouldnt a new flywheel **** it up too? if ne think im going to say that less weight on the cranks (in the way of flywheels and pullies) is going to be better on the barrings of the engine. as long as its not a hack product that is not balance properly.
as for underdrive... im not a fan. since i have a b16 with just the altentor being driven im more into just having the single pully ,that i believe unorthedox makes, rather then the extra weight from the power-steering and AC.
its a general rule that the lighter you are the faster you are. this is compounded when that weight is taken off of the rotating mass of the engine. (lighter flywheel = faster revs)
the same will be true with the pullies. it wont be a ton but it will be something.
over all you just need to deside if you want to shell out the money to gain a slight gain, or if you want to save it and just get something with a bigger bang for the buck.
(forgive me if this makes noooo sense.. its way to late
as for underdrive... im not a fan. since i have a b16 with just the altentor being driven im more into just having the single pully ,that i believe unorthedox makes, rather then the extra weight from the power-steering and AC.
its a general rule that the lighter you are the faster you are. this is compounded when that weight is taken off of the rotating mass of the engine. (lighter flywheel = faster revs)
the same will be true with the pullies. it wont be a ton but it will be something.
over all you just need to deside if you want to shell out the money to gain a slight gain, or if you want to save it and just get something with a bigger bang for the buck.
(forgive me if this makes noooo sense.. its way to late
#7
Z20 H8R
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my b16 is underdriven with a unorthadox pulley. its the single one liek mentioned above. thats all i got on it though no other lightened pulleys. i have a 800watt system in my car too. i havent drained my battery or anything but i also have a steffening capacitor for my system. with the crank and the lightweight flywheel its a considerable difference (or atleast it was until i did my other stuff) when i raced stock B16's.
#8
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i would say 10hp is plausible in a v6-v8, but in a very efficient 4banger your gains may be closer to 2%. every little bit helps.
i dont see how this would harm your engine though, the crank spins as the crank spins, if there is less weight on, well hurray.
i dont see how this would harm your engine though, the crank spins as the crank spins, if there is less weight on, well hurray.
#9
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the thing is that your not going to gain hp.
your going to gain throttle responce and just more power is going to get to the ground. so there is less lost in the way of rotaional inertia
your going to gain throttle responce and just more power is going to get to the ground. so there is less lost in the way of rotaional inertia
#10
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Early UR pulleys weren't balanced as carefully as they are now. Now the only drawbacks to them is alternator wear [the voltage regulator has more stress put on it when asked to produce the same voltage with fewer RPM available] and headlight dimming at idle.
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