Engine Aem Pulleys

Aem Pulleys

Are the AEM pulleys a good buy?

Niyet

Re: Aem Pulleys

Not pulley(s), just PULLEY. AEM only makes an alternator pulley for our cars. Plus I heard the belt that's included does't fit right. Better to go with Unorthodox Racing. They make both the alternator AND underdrive crank pulley for our cars. That will net you a bigger performance gain than just the AEM lightened/enlarged pulley alone.

what type of performance gain would you expect from the unorthodox racing you described kingkuei? i haven't looked too much into a pulley or alternator what ahve ya... so i don't know much about it.. thanks

Auto Specialties Performance makes a CNC machined, hard anodized, aviation grade (6061 T6) billet aluminum underdrive crank pulley for half the price of an Unorthodox Racing crank pulley. http://www.rpmoutlet.com/aspimp.htm#toyota
Part # 331130... They claim a net gain of 8 HP. It also increases accessory life and fuel mileage. I should get mine this week.
http://www.aspracing.com/frame.htm

that is not too bad of a gain if it is true.. good find

Something that I posted some time ago... worth a read.

Something you might want to think about regarding "power" pulleys. A word from Steve Dinan, perhaps the most recognized and respected BMW tuner...

http://dinancars.com/html/danger_of_power_pulleys.htm

i heard that if you get pullies, its not good to have a system also... is this true?

Yup. The underdrive crank pulley will reduce the power output. Not a problem for me though. With all the electrical stuff I'm going to be running, I was going to hook up a second battery in the trunk to power it all anyway.

Okay so our Corollas have a harmonic damper at the crank assembly, right? Does the installation of a new pulley REQUIRE the removal of the damper?

Yeah, I was aware of such a concern and I've seen varying opinions on it... I will check my own stock pulley and see if it has a built-in harmonic balancer. I did find some interesting info on the 1ZZ FE's development and design. http://www.spyderchat.com/1zzfe.pdf
Note special rigid crankcase design, and reduced reciprocating mass (page 9+10) for better noise and vibration control...

The BMW that Steve Dinan refers to is an M3 E36 (3.2 liter inline 6). Reliability problems have been encountered by eliminating the harmonic balancer on larger and longer, multiple cylinder engines. Auto Specialties Performance actually makes 'Harmonic Dampner' pulleys for most 6 and 8 cylinder applications.
Quoted from my Bosch SAE (Society of Automotive Engineers) Automotive Handbook under 'Crankshaft Vibrations': "Bending vibrations are significant with a small number of cylinders, because the crankshaft and the necessary flywheel form an oscilatory system with a low natural frequency. Beginning with a 3-cylinder engine, bending vibrations are uncritical. By logical extension, this also applies to the crankshaft longitudinal vibrations induced by bending vibrations. But, with increasing numbers of cylinders, the torsional vibrations of the resonant system formed by the crankshaft, connecting rod and piston are dangerous....The torsional vibrations of the crankshaft must be reduced to uncritical values through the use of vibration dampers (e.g. bonded rubber vibration dampers or viscous vibration dampers)....Free inertia effects applied to the piston, connecting rod and crankshaft assembly (force and moment) can be eliminated by rotating balancing systems. Internal bending moment is reduced by use of counterweights and stiff engine housing."
As mentioned on page 10 of 'Development of Toyota 1ZZ FE Engine'http://www.spyderchat.com/1zzfe.pdf "the mass of 15% of all parts that make reciprocating motion has been reduced which has resulted in a reduction of 12% in rotary secondary reciprocating inertia force. (rotating balancing system)" It also features an advanced compact, rigid crankcase design, further reducing vibrations...
At any rate, I shall boldly subject my finely engineered Corolla to a grueling long term test, and we shall see how she holds up...

I'M WITH YA BROTHA! I'm ordering up the UR Ultra SS set since it also has the alternator pulley. At least some time down the line we'll be able to compare differences between the two. Right on! Live on the edge a little!

Found this as part of the UR FAQ:

4) "Is my crank pulley a harmonic/torsional/vibration damper or a harmonic balancer?"

People are getting the pulleys confused with the harmonic dampers found on some V6 / V8 engines. "Harmonic Balancer" is a term that is used loosely in the automotive industry. Technically, this type of device does not exist. The "balancer" part comes from engines that are externally balanced and have a counterweight cast into the damper, hence the merging of the two terms. None of the applications that we offer utilize a counterweight as part of the pulley as these engines are internally balanced.

The pulleys on most of the new import and smaller domestic engines have an elastomer (rubber ring) incorporated into the pulley that looks similar to a harmonic damper. The elastomer in the OEM pulley serves as an isolator, which is there to suppress natural vibration and noise from the engine itself, the A/C compressor, P/S pump, and alternator. This is what the manufacturers call NVH (Noise Vibration & Harshness) when referring to noticeable noise and vibration in the passenger compartment. It is important to note that in these applications, this elastomer is somewhat inadequate in size, as well as life span, to act as an effective torsional damper. If you look at the pulleys on some of the imports there is no rubber to be found at all. We have samples of these, mostly from Acura/Honda, the Nissan Altima, 1.8L Eclipse, 2.3L Fords, Chrysler 2.2L's, and 1.8L VW's, to mention a few. This is not to say that with our pulleys you will hear a ton of noise or feel more vibration from your engine compartment. Most who have installed and driven a vehicle with our pulleys will notice the engine actually feels smoother. This is a natural result of replacing the heavy steel crank pulley with a CNC-machined aluminum pulley. NVH is variable and unique to every car. NVH will increase with the installation of an aftermarket intake and/or exhaust, for example. Think of OEM intake systems in newer cars, they use baffles and resonators in the intake to quiet all the intake noise. Aftermarket intakes eliminate these resonators and create dramatic increases in engine noise from the throttle opening and closing. So to most tuners, certain types of NVH can make the driving experience more enjoyable.

The purpose of a traditional harmonic damper is to protect against crank failure from torsional movement. This is not necessary in most modern engines because of the many advances in engine design and materials. Factors such as stroke, displacement, inline, V configurations, power output, etc., do determine when and how these harmonics and torsional movements occur.

Again, there is a lot of internet hearsay about the pulleys. When motor failures occur, too often people are quick to blame the pulley first, rather than taking the time to look logically into why there was a problem. We hope that after reading this you will understand the crank pulleys better.

Good to hear that, KingKuei...That rubber ring is in fact visible on our hefty steel crank pulley but, I like the idea of a light balanced piece spinning at the extremity of the crank. I am still waiting on my ASP pulley, by the way.