Pulleys
#1
Ok, so Rick is having a G/B with the JSpeed pulleys among other things and I was wondering... What do these pulleys do?
Underdrive Pulley does...
(As opposed to Overdrive Pulleys?)
Cam Sprocket Timing Pulley does...
(This one looks like it's for the exhaust cam, correct? Work with 1.8L cam swap?)
Power and Water Pulleys do...
(Power = Power Steering?)
Kspec has an Intake Cam Sprocket Pulley from Rside, if you have the aftermarket Exhaust Cam Sprocket Pulley do you need the aftermarket Intake Cam Sprocket Pulley so that the adjustments you make will match?
Thanks in advance to anyone who helps!
Underdrive Pulley does...
(As opposed to Overdrive Pulleys?)
Cam Sprocket Timing Pulley does...
(This one looks like it's for the exhaust cam, correct? Work with 1.8L cam swap?)
Power and Water Pulleys do...
(Power = Power Steering?)
Kspec has an Intake Cam Sprocket Pulley from Rside, if you have the aftermarket Exhaust Cam Sprocket Pulley do you need the aftermarket Intake Cam Sprocket Pulley so that the adjustments you make will match?
Thanks in advance to anyone who helps!
#2
Aftermarket underdrive pullys are alot lighter then stock, usually around a 75% weight loss difference!! (and in some cases, a different diameter) to free up horsepower.
The cam sprocket is used to either advance or retard cam timming.
The cam sprocket is used to either advance or retard cam timming.
#4
Yes, I do not know about the Jspeed.. but the Unorthodox racing underdrive crank pully weighs 3 1/2 pounds less than stock. That is a LOT of rotational weight. Being an underdrive pulley, it will spin the other aux pulleys slower, freeing up more horsepower as you get a differnt ratio on pulleys and you are turning them slower.
Cam sprocket pulleys work well with the stock, 1.8 and the XD cams. You use it to fine tune to the combustion process with the timing of the car. If I was to invest in one of these, I would get the intake sprocket as well, so you can really fine tune the engine through both cams.
Cam sprocket pulleys work well with the stock, 1.8 and the XD cams. You use it to fine tune to the combustion process with the timing of the car. If I was to invest in one of these, I would get the intake sprocket as well, so you can really fine tune the engine through both cams.
#5
You won't notice any hp gains with adjustable cam gears. All they allow you to do is advance or retard the cam timing, which in turn just moves your powerband. So, say you retard the cam timing, your power will shift to the lower/mid-range RPMs. Most people only upgrade to adjustable cam gears when they upgrade camshafts, that way they can fine tune where the extra hp gains from the camshafts will be. Also, normally, you only want to adjust the intake side, unless maybe you're turbocharged...?
#7
Here is a link with more information about pulleys: http://www.rdtiburon.com/index.php?showtopic=7630&st=40
#8
I do not know know about adjusting for turbo.. but they are a great thing if you have shaved the head.
You also have to remember, these engines are mass produced, tolerances slip as the machines that produce the parts wear. I would hazard a guess that at least half of all engines built are slightly out of their engineered toleralces when they leave the factory. As such, adjustable cam gears CAN be used to gain some horsepower by bringing the timing back to it's designed point.
Also, some of us are running the intake cam from the earlier 1.8, there is probably some hp to be gained by adjusting that to perfect. Just some warning though, this is not a cheap process. We are talking dyno time, making a pull, adjusting the cams, making a pull, adjusting the cams... over and over and over until everything is spot on.
You also have to remember, these engines are mass produced, tolerances slip as the machines that produce the parts wear. I would hazard a guess that at least half of all engines built are slightly out of their engineered toleralces when they leave the factory. As such, adjustable cam gears CAN be used to gain some horsepower by bringing the timing back to it's designed point.
Also, some of us are running the intake cam from the earlier 1.8, there is probably some hp to be gained by adjusting that to perfect. Just some warning though, this is not a cheap process. We are talking dyno time, making a pull, adjusting the cams, making a pull, adjusting the cams... over and over and over until everything is spot on.
#9
Yeah he is right, basically your moving a little more power up in the powerend to gain more power at the top. For the money for the gears and the dyno time, its really not worth the money unless you're seriously working on fine-tuning an engine.