Light weight pulleys-Worth it or worthless?
- Thread starter Logan
- Start date
Worthless.
You now have to worry about possible oil leaks through the seal, unbalanced pulley issues, etc.
If you go the light weight AND under-driven route, you now have lower voltage from the alternator, reduced output air conditioning, water pump, power steering pump, etc, etc, etc.
Completely not worth the cost or "gains."
Just save up for a supercharger and then call it quits, otherwise don't bother with "performance."
(my $0.02)
You now have to worry about possible oil leaks through the seal, unbalanced pulley issues, etc.
If you go the light weight AND under-driven route, you now have lower voltage from the alternator, reduced output air conditioning, water pump, power steering pump, etc, etc, etc.
Completely not worth the cost or "gains."
Just save up for a supercharger and then call it quits, otherwise don't bother with "performance."
(my $0.02)
- Location
- Vancouver, Canada
I remembered hearing about losing torque if the pulley is changed to light weight and increase the strain on the alternator since now your crank pulley is running faster and drive the rest of the pulleys faster. I can't 100% confirmed but I believe this has been an on-going debate on several G & Z forums.
- Location
- Los Angeles, CA
- Car
- 05 FX35 RWD
Throttle body spacer. Lots of debate, no downside . . at least on a 35. I love mine
Pulleys? . . too many issues along with that one, bus some like it
Pulleys? . . too many issues along with that one, bus some like it
- Location
- Dallas, TX
- Car
- 2007 FX35 RWD
The thing always kept me away was the install. It's not something that seemed easy enough to install. I would never do underdriven, but I don't have anything against a lightweight one.
- Location
- Southern California
I have the UR underderive pulley and like it. I say worth it. Make sure you buy UR or Stillen, others are knock offs.
some go for the stock diameter and have reported that they dont feel any difference. I like my underdrive and worth my money.
some go for the stock diameter and have reported that they dont feel any difference. I like my underdrive and worth my money.
twistedtahoe
Member
- Location
- so cal
I've done under drive on a chevy S-10 with a 4.3L and loved it. I am going to be doing UR underdrive pulley set on my FX soon. I have access to a full auto garage lift and all...I can turn a wrench so install should be easy plus not running any electrical compontents i'm not worried about voltage drops. I ran 2 amps in my S-10 no prob
- Location
- Portland, OR
For me the cost alone of the pulleys (and TB spacer) is a big enough downside to outweigh the unproven benefits. That said, I spend countless man hours tinkering with what some consider nonsense.
I think if I got a good deal on some HIGH QUALITY (balancing is huge) OEM sized lightweight pulleys, I'd throw them on just for something to do. A little TQ loss (It can't be a noticeable amount...) is ok with me if it means a slightly more efficient/responsive motor. I definitely wouldn't install the under-drive versions though per Frankiago's comment above...
I think if I got a good deal on some HIGH QUALITY (balancing is huge) OEM sized lightweight pulleys, I'd throw them on just for something to do. A little TQ loss (It can't be a noticeable amount...) is ok with me if it means a slightly more efficient/responsive motor. I definitely wouldn't install the under-drive versions though per Frankiago's comment above...All of that is completely not true
The crank pulley will NOT run faster no matter what, it is completely dependent on the crank shaft, which is completely dependent on your engine's RPM!
An under-driven pulley, on the other hand, will turn the belt less RPM for a given crank RPM due to the diameter difference. This will SLOW DOWN the belt and UNDER-DRIVE your accessories, aka turn them SLOWER. There is no need to worry about your belt-driven accessories, they can take the slower speed just fine.
Install is a PITA, even on a lift. I had no way of locking the transmission. When I tug, the crank turns. The ONLY WAY I could get the damn pulley off was by using a breaker bar and wedging it onto pavement and then crank the motor for a second or two (ignition). This slammed the breaker bar into the pavement, took a small gouge out of the Earth and made the crank pulley bolt finger tight
- Location
- Los Angeles, CA
- Car
- 05 FX35 RWD
Too daring just for a pulley
twistedtahoe
Member
- Location
- so cal
Install is a PITA, even on a lift. I had no way of locking the transmission. When I tug, the crank turns. The ONLY WAY I could get the damn pulley off was by using a breaker bar and wedging it onto pavement and then crank the motor for a second or two (ignition). This slammed the breaker bar into the pavement, took a small gouge out of the Earth and made the crank pulley bolt finger tight
Thats NUTZ....can't you just turn the car off in gear and set the parking brake? I plan on using an impact gun where i can.
- Location
- Portland, OR
...
Install is a PITA, even on a lift. I had no way of locking the transmission. When I tug, the crank turns. The ONLY WAY I could get the damn pulley off was by using a breaker bar and wedging it onto pavement and then crank the motor for a second or two (ignition). This slammed the breaker bar into the pavement, took a small gouge out of the Earth and made the crank pulley bolt finger tight
Yikes.
I've always just had someone step on the brakes while breaking the crank bolt free on other cars. I don't see why you would even need a lift for the FX pulleys. There's tons of room in there...
An impact wrench would probably be best.
- Location
- Southern California
see JB thread about the pulley....
///1780
also this one from rookie
///275
I know psiclne has the stock size pulley and he had told me he wanted to upgrade to the underdrive one.
///1780
also this one from rookie
///275
I know psiclne has the stock size pulley and he had told me he wanted to upgrade to the underdrive one.
- Location
- Vancouver, Canada
All of that is completely not true
The crank pulley will NOT run faster no matter what, it is completely dependent on the crank shaft, which is completely dependent on your engine's RPM!
An under-driven pulley, on the other hand, will turn the belt less RPM for a given crank RPM due to the diameter difference. This will SLOW DOWN the belt and UNDER-DRIVE your accessories, aka turn them SLOWER. There is no need to worry about your belt-driven accessories, they can take the slower speed just fine.
Install is a PITA, even on a lift. I had no way of locking the transmission. When I tug, the crank turns. The ONLY WAY I could get the damn pulley off was by using a breaker bar and wedging it onto pavement and then crank the motor for a second or two (ignition). This slammed the breaker bar into the pavement, took a small gouge out of the Earth and made the crank pulley bolt finger tight
Thanks for the correction Frankiago
. More information learned toward my FX. Appreciated. :.smile:Impact gun would be VERY useful... I didn't have one so I couldn't do INSTANT torque on the bolt. Trust me, nothing I did worked, I tried damn near every trick in the book. I even did a risky trick that didn't work so well:
Pull a spark plug, coil some nylon rope into where the spark plug was, turn the crank manually until the piston sandwiches the nylon on an up-stroke, then the crank will no longer turn freely allowing you to break the bolt free.
That didn't work, I didn't get enough nylon rope in there and I didn't feel comfortable putting any more in
There's no need for a lift, and should be no need for the brakes if the car is on the ground (I didn't even put the FX on jack stands when I did it, like you said, tons of room). There's no way I could turn the crank hard enough to spin the wheels
As for another means of stopping the crank from turning... there isn't one that I know of. The way the automatic transmission works is basically two "fans" within the torque converter. One side is attached to the crank shaft the other is "floating" in the center and attached to the transmission's gears, while the housing surrounding this "floating" fan has fixed vanes that return the transmission fluid to the "suction" of the first "fan." There is no physical linkage between the crank shaft and the gears, so the crank pulley is independent of what the gears/tires/drive-shaft/etc are doing.
In essence, what I was doing when turning the entire crank was sliding the pistons up and down the cylinders, rotating the cam shafts via the timing chain and turning the first "fan" within the torque converter and pushing fluid through to the other side "fan" (turbine).
What I'm trying to get at is: no way to stop this thing from spinning unless you stop the pulley from rotating (get a friend to loop the belt around ONLY the crank pulley and pull hard while you turn the crank bolt), stop the crank shaft from rotating (shove something that won't produce debris into the cylinder to wedge between the head and the piston), or use a torque wrench to put an instant torque on it instead of gradual.
The other way around this is to make the BOLT not rotate while the crank shaft DOES rotate
No problem! Forums can be great resources to learn from and at the same time petri dishes for wrong information to grow :tonguey:Thanks for the correction Frankiago
PS: I used terms like "fan" to describe turbines and whatnot to provide a decent mental image of what's going on.
- Location
- brooklyn, ny
cranking/tapping the engine works well & I've done it like that many times on many cars, it's quick & if the bar is long enough & loaded right it's not so dangerous or risky at all. you just want to make sure something is disconnected so it can'ty actually start, but the way to do it without doing that would be to remove the starter & hold it from the flywheel. most times if the radiator/condenser is still in the car there is not enough room for an impact gun even if you do have one.
- Location
- Portland, OR
Yes, I just didn't have the right tool to remove the oem alt pulley so I never unwrapped the new one.
Interestingly, this is how UR markets their accessory pulleys:
-SOURCE
I'm not going to say it's a lie for sure, but it's certainly not what I found to be true. According to my scale, there could only possibly be a .04lbs difference between the two which is just over 6%.
***To it's credit, the UR pulley is very pretty and is obviously manufactured to a much higher quality standard than the oem version...if that matters.
For reference, here's a pic of Jumbo's UR pulleys installed. the one I installed today ([ST]water pump[/ST] idler) is the larger of the two silver ones.
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- Location
- Dallas, TX
- Car
- 2007 FX35 RWD
Thought about modifying it yourself at all?
- Location
- Portland, OR
Modifying what?
____________________
Here is the UR [ST]water pump[/ST] idler pulley next to the oem unit, taken just before the weigh-in.
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- Location
- Inland Empire, CA
- Car
- 2003 FX45
Yep, it is pretty.
So did you do water pump only? Are you going to do others?
So did you do water pump only? Are you going to do others?