Underdrive Pulley
#27
Registered
iTrader: (2)
Just wanted to confirm the AP Pulley DOES fit on the s2 with no issues. The way it's machined if the holes aren't lining up, you just have to 180 it and everything lines up as it should. I'll also agree with what has already been mentioned, there's no noticeable gain or difference from stock.
Last edited by MinHoSII; 02-14-2012 at 03:26 AM.
#28
Banned
iTrader: (1)
Just wanted to confirm the AP Pulley DOES fit on the s2 with no issues. The way it's machined if the holes aren't lining up, you just have to 180 it and everything lines up as it should. I'll also agree with what has already been mentioned, there's no noticeable gain or difference from stock.
Now to deal with my check engine light for cylinder 2 misfire
Now to deal with my check engine light for cylinder 2 misfire
Last edited by RMXG8; 02-13-2012 at 08:31 PM.
#29
Super Moderator
Waste of $$$'s as usual...
#30
Registered
Just wanted to confirm the AP Pulley DOES fit on the s2 with no issues. The way it's machined if the holes aren't lining up, you just have to 180 it and everything lines up as it should. I'll also agree with what has already been mentioned, there's no noticeable gain or difference from stock.
Not sure why yours fit bro, but we turned mine every way imagineable and no way that thing was going on my car .... so I guess there's a possiblility your car received the s1 version from the factory for the pulleys .... which i've heard happens sometimes .... but wasn't anyway they were fitting on mine.
From what i've read, pretty much a complete waste other than appearance anyway.
#31
Registered
iTrader: (2)
Not sure why yours fit bro, but we turned mine every way imagineable and no way that thing was going on my car .... so I guess there's a possiblility your car received the s1 version from the factory for the pulleys .... which i've heard happens sometimes .... but wasn't anyway they were fitting on mine.
From what i've read, pretty much a complete waste other than appearance anyway.
From what i've read, pretty much a complete waste other than appearance anyway.
#32
#35
Smoking turbo yay
Yeah, better check it out.
The only pulley that's safe to underdrive is the AC pulley, but then you may as well just remove the AC altogether.
The only pulley that's safe to underdrive is the AC pulley, but then you may as well just remove the AC altogether.
#37
Smoking turbo yay
Mind to elaborate?
Most of the posts before have said it's not worth it, and the explanation from RIWWP makes sense.
Most of the posts before have said it's not worth it, and the explanation from RIWWP makes sense.
Pulleys
Don't. You might ask "why?", so here is an explanation:
There are 2 "benefit" points to changing to aftermarket pulleys.
The 1st "benefit" is a reduction in the weight of the pulley. This is a similar concept to going with a lightweight flywheel to assist with a more responsive engine. The problem is, the weight you are saving is very very very small, and it's close to the center of rotation, so there is very little gain by reducing it. It takes roughly 10lbs of weight saved at inch from the center of rotation to equal the interia savings of 1lb of weight saved at 10 inches from the center of rotation. Lightweight flywheels are still rather large in diameter (almost larger than the core engine block), and much of the weight stripped is near the outside of the flywheel. Pulleys have only a few inches and at most maybe a pound, and most of the weight to remove is near the center. It just isn't going to give noticeable gains for the price.
The 2nd "benefit" is to underdrive one or more accessories. The problem with this is that under driving your alternator is bad for your electronics and battery, and underdriving your water pump can have significant penalties to your ability to keep the engine cool. And all it takes is 1 overheating, or even undetected localized hot spotting, and your housings can warp and your engine is done. Underdriving your A/C is without penalty, but removing the AC system completely would accomplish the same AC effectiveness as underdriving it, and leave your car lighter and without the AC compressor drag at all, so it's the better choice (and cheaper).
Don't. You might ask "why?", so here is an explanation:
There are 2 "benefit" points to changing to aftermarket pulleys.
The 1st "benefit" is a reduction in the weight of the pulley. This is a similar concept to going with a lightweight flywheel to assist with a more responsive engine. The problem is, the weight you are saving is very very very small, and it's close to the center of rotation, so there is very little gain by reducing it. It takes roughly 10lbs of weight saved at inch from the center of rotation to equal the interia savings of 1lb of weight saved at 10 inches from the center of rotation. Lightweight flywheels are still rather large in diameter (almost larger than the core engine block), and much of the weight stripped is near the outside of the flywheel. Pulleys have only a few inches and at most maybe a pound, and most of the weight to remove is near the center. It just isn't going to give noticeable gains for the price.
The 2nd "benefit" is to underdrive one or more accessories. The problem with this is that under driving your alternator is bad for your electronics and battery, and underdriving your water pump can have significant penalties to your ability to keep the engine cool. And all it takes is 1 overheating, or even undetected localized hot spotting, and your housings can warp and your engine is done. Underdriving your A/C is without penalty, but removing the AC system completely would accomplish the same AC effectiveness as underdriving it, and leave your car lighter and without the AC compressor drag at all, so it's the better choice (and cheaper).
Last edited by UnknownJinX; 04-28-2018 at 01:13 AM.
#38
Boosted Kiwi
iTrader: (2)
Same for the alternator. Underdrive only a negative for those that either sit in traffic a lot or run a large electrical load.
The overall benefit is indeed small however. FWIW i don't run one with a turbo setup .... but I don't rev to 9000 either .
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