What is the difference between Unorthodox Pulleys and Underdrive Pulleys?

Whats the best?

Thanks.

 

nuthing, Unorthodox Underdrive Pulley

 

unorthodox makes a crank pulley and accessory pulleys, which are the power steering and alternator pulleys. however the UR accessory pulleys don't underdrive, they're just lightweight-thus less inertia needed to rotate/causes less drag on crank.

aem only makes accessory pulleys which underdrive which have a diameter larger than stock. this allows the accessories to be "underdriven" because the larger pulleys will spin them slower thus less drag on the crank.

even though i haven't seen a head to head comparison of the aem and ur pulleys, the aem pulleys will most likely be your better bet.

 

unorthodox does make an underdrive pulley. from the source:

Unorthodox Racing Ultra Street lightened underdrive crank pulleys. Our pulleys are CNC-machined from lightweight 6061-T6 aluminum billet. Premium U.S. made 6061-T6 aluminum billet ensures the consistency of the material's strength and balance. Tolerances are held to within .001", and numerous machining steps are used to ensure the lightest possible design. In addition to fit, finish is just as important and each piece is representative of this. Every pulley is inspected multiple times from machining to anodizing to stocking and finally at shipping time. If at any point a pulley does not pass inspection it is pulled from production.

Unorthodox Racing lightened underdrive crank pulleys on average can provide gains of 5 to 12 HP and 4 to 8 lbs.-ft. on normally aspirated engines and 8 to 16 HP and 8 to 18 lbs.-ft. on forced induction engines. Higher gains are possible. For example, a Nissan 300ZX twin-turbo saw gains as high as 37 HP and 45 lbs.- ft. on the dyno just by replacing the stock crank pulley with our Ultra S lightened underdrive crank pulley.

Power gains are obtained in two ways. First, and most important, is the weight loss. An average of 2.7 HP is gained from every pound lost off the crank shaft. 85% of our gains are from weight loss.

The rest of the gains are from underdriving, which accounts for about 15% of the total gains. We do not push underdriving for two main reasons. Our main reason is to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving. In most applications all of our underdriving is done with the crank pulley, not the accessory pulleys. This is done so maximum weight loss can be achieved at the crank where most of the horsepower gains are found.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DubbleD &raquo;</TD></TR><TR><TD CLASS="quote">We do not push underdriving for two main reasons. Our main reason is to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving. In most applications all of our underdriving is done with the crank pulley, not the accessory pulleys. This is done so maximum weight loss can be achieved at the crank where most of the horsepower gains are found.
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did you even read what you posted?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by del_parker &raquo;</TD></TR><TR><TD CLASS="quote">

did you even read what you posted?</TD></TR></TABLE>

Yes. What it says is unorthodox doesn't push underdriving as most of the benefits come from reduced weight, meaning they don't go overboard. The Crank pulley is in fact smaller, as the OEM pully will not fit into the box the Unortho comes in. What they are saying is they don't change the size of the accessory pullies *along* with the size of the crank because the benefits vs downfalls for street driving (with the SS is ment for) has more downfalls than benefits

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rjr162 &raquo;</TD></TR><TR><TD CLASS="quote">

Yes. What it says is unorthodox doesn't push underdriving as most of the benefits come from reduced weight, meaning they don't go overboard. The Crank pulley is in fact smaller, as the OEM pully will not fit into the box the Unortho comes in. What they are saying is they don't change the size of the accessory pullies *along* with the size of the crank because the benefits vs downfalls for street driving (with the SS is ment for) has more downfalls than benefits</TD></TR></TABLE>

and there ya have it......

 

this is to both of you... did i say anything about the crank pulley besides the fact UR makes one? NO! what did i say? i said the UR accessory pulleys don't underdrive. both of you have poor reading comprehension skills.

 

so. point of the story is.... ??? &lt;-------------------

ive heard stories about lightened pulleys and how they are bad? anyone one else know of these stories? can you people give me ups and downs to having an after market pulley kit?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Elkins911 &raquo;</TD></TR><TR><TD CLASS="quote">so. point of the story is.... ??? &lt;-------------------
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aem pulleys underdrive and ur's accessory pulleys don't

supposedly UR's crank pulley is bad and everyone says so because some guy on ntpog.org had a knock off[copy] pulley and later had issues with his bearings.

 

but everything should be fine? i have a bad alternator pulley and i was thinking about changing out all them *******. but with the stock pulleys costing almost as much for aftermarket... it has come into mind. which is better to go with? aftermarket or OEM.

 

the pulley itself was bad?

if you have to replace them and don't mind dim lights at idle, go ahead and get the AEM pullies.

the only pulley really worth getting would be the crank pulley, the rest won't result in much more, if any, power increase.

 

So if we talk about weight loss. Can anyone confirm that 2.7HP on every pound less on the crank? Then changing from a stock flywheel (20 lbs) to the lightweight (8 lbs) stuff should bring (20-8) *2.7HP= 32.4 all new HP I don't think it's possible... What's your experience? How much did you gain changing your flywheel?
Thanks
pentaq

 

how can someone still say that the UR crank pulley doesnt underdrive after the company states that 15% of their gains come from underdriving???? wow. the UR pulleys r awesome products. i have mixed opinions about the AEM pulleys. they just dont seem worth the money. its ur decision

 

Just thought I would add, my best advise would be to keep your factory crank pulley (balancer) and simply buy the individual pulleys for the accessories. The problem lies in the fact that the factory Honda crank pulleys are actually harmonic dampeners, containing a dividing layer of rubber between the inner and outer section of the pulley effectively dampening vibrations that would normally harm the main bearings. A solid pulley (UR) does not dampen these vibrations at all, severly reducing bearing life.
A while back I actually spent the money and bought an UR crank pulley, only to eventually straight up trade it for a new factory Prelude pulley.

Please, think about it.

 

Also, remember which vital part resides directly behind the crank pulley and would also be negatively affected by an increase in vibration leading to a possible failure......your oil pump.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DubbleD &raquo;</TD></TR><TR><TD CLASS="quote">how can someone still say that the UR crank pulley doesnt underdrive after the company states that 15% of their gains come from underdriving???? wow. the UR pulleys r awesome products. i have mixed opinions about the AEM pulleys. they just dont seem worth the money. its ur decision </TD></TR></TABLE>

the UR crank pulley does the underdriving. the accessory pulleys do not underdrive, they're basically the same as the stock pulleys except less weight.