Overrunning Alternator Decoupler (OAD) Pulley Mod

@dev re: Litens in Dayco box, I caught this in the Litens write up - http://www.decouplerpulley.com/basics.cfm

What other manufacturers (other than Litens) produce OAD™ pulleys?

No other manufacturers, in North America or around the world, produce OAD™ pulleys. This technology is fully protected by patents and intellectual property laws. Some other manufacturers attempt to market their "Overrunning Alternator pulley" (OAP) as an alternative to OAD™ technology, but the performance is not comparable in any way. These one-way pulleys do not adequately absorb drive belt system vibration.

Does this then apply to the Toyota version?

@ISpy

No problem. No one can read everything all the time 🙂

Very interesting observations from the Litens site. OAD is definitely not the same as OAP. So if Toyota's part is an OAD they are getting it from Litens just the same as Chrysler. Since the same part is used for both, I'm guessing Toyota is using the Litens manufactured part. 

On another note, I have seen Litens pullies stamped both "Canada" and "China" so far. I don't know if there is a USA factory as well but if the previous are the only two choices.... Might be worth asking a merchant about before purchasing. 

@cyclehead

Glad you're on board! Really hope it helps the SMT. Thanks for sharing the pics. As far as I know, pulley measurements are supposed to be based off the major rather than minor. As long as it's done on the belt surface and not the lip of the pulley. Looking forward to your impressions as well.

Posted by: @ispy

@dev re: Litens in Dayco box, I caught this in the Litens write up - http://www.decouplerpulley.com/basics.cfm

What other manufacturers (other than Litens) produce OAD™ pulleys?

No other manufacturers, in North America or around the world, produce OAD™ pulleys. This technology is fully protected by patents and intellectual property laws. Some other manufacturers attempt to market their "Overrunning Alternator pulley" (OAP) as an alternative to OAD™ technology, but the performance is not comparable in any way. These one-way pulleys do not adequately absorb drive belt system vibration.

Does this then apply to the Toyota version?

  Very good read. I do deep searches to find gems like this but this one escaped me.  

 From the looks of it the Toyota OAD pulley looks different then this one from the pictures. The front lip is longer and on the rear its not as wide. Basically does not have that additional rim on the cone that screws on.   

It is possible that although Litens is the one that owns the patent, it is also possible that either the patent ran out or it was licensed and they are manufactured by many different houses.  

 As far as how much better or worse I have read that these can prematurely fail as early as 60k miles but on the average  they can last well over 100k miles.  I do believe it because none of us until a year ago knew anything about them and if they were a common point of failure the journalists would have a field day with it.  Most alternators use to fail around 60-80k but these days everything is lasting much longer and now with this part I imagine belt and tensioner life has tripled to a point where these items might out last the first owner.  

 It just amazes me how much better engines are with fewer serviceable parts but it seems there are a few hiccups when they try to get the most efficiency out of them with low tension piston rings and GDI issues.  It is quiet possible that car manufactures might have to scale down after this pandemic because people may get thrifty with what they have and not like the old days where reliability was a major factor towards a new car purchase. 

Im finishing up. Im afraid I had to do the replacement engine mount at the same time so my impressions will be skewed. 

 My Milwaukee M12 impact was able to take off the nut easily and its only rated for 110 ftlb reverse torque.  

 I slipped just the alternator belt off so Im going to see if its possible to get the belt back on and at the same time hold the tensioner as a one man operation.

All finished and went for a test drive. I did some acceleration deceleration and basic shifting. I did not notice that much of a difference. I did feel the clutch engage a little better at least I think so. I drove back home and checked to make sure everything was in order and there were no abnormal sounds, actually the engine seemed a little quieter which changed the tone of  how I hear my exhaust in a good way. I then taken it for a performance drive and it was not much remarkable. It wasn't slow, it wasn't fast it was little smoother but not a night and day difference. When I did go to blip the throttle when downshifting through the gears then it became apparent that it was better. It was as if the blips were crisper which I really liked.  

@dev

basically the same as my experience with the lighter underdrive pulley.

Two ways to Rome: One with less load on the belt and maybe a whiff better fuel economy and the same charge capacity, the other with less weight and less rev load on the alternator and a whiff better performance.

Awaiting the lightweight carnk pulley. At 1.2 kilo lighter should be another whiff better performance and brisker blip.

p.s. just got back from a date; the fist time going out at night in 12 weeks!! The return home through the mountains in the small hours of the night with nóóóbody on the road; alone with the exhaust note, mán what a treat  is this car 😀 

I did another drive just to make sure and this time I could feel the difference and I did but  you have to pay attention because it feels completely OEM. Its does make the engine feel smoother and if I drop my  kevlar clutch too early I could feel it jerk but this time there were no jerks just smooth engagement similar to oem.  Overall a little smoother than before. Looking at the belt and tensioner at idle it look completely stationary.  Its not a drastic change its subtile.  

 One other thing I noticed and I do not know if its related but I hear more crackles and pops when I shift at higher rpms.  

You guys crack me up .... there's some sensitive dudes right there ....lol 

It's the kind of mod that grows on you. First impressions aren't much but in the next several drives you will really begin to feel the difference. It is subtle, and does have an OEM feel to it, but it helps on every shift.... Up or down. It is much more forgiving if you don't nail the right clutch/throttle positions. It helps when you go from WOT to closed, or vice versa. Smooth and subtle go hand in hand. If you really want to be able to gauge the difference... Drive with the OAD for a few weeks, then swap back to fixed, or jump into someone's Spyder that doesn't have an OAD. When you move from smooth and subtle back to harsh... The difference will be much more apparent.

Nonetheless I am glad you have noticed a positive difference!

Posted by: @phats

You guys crack me up .... there's some sensitive dudes right there ....lol 

  In that case you are really gong to love my new out of focus pictures. It will certainly make you a sensitive irritated dude.  

@marsrock7

 I will keep with it.  There is certainly something different about it especially the timing of the shifts but that could also be related to the softer motor mount I added.  Having two changes at once could also skew the perception.  It is weird because when Im observing the belt side I can now hear the idler pulley more distinctly which wasn't there before. I have a feeling somethings may have quieted down unmasking other sounds.  I have to say those crackles and pops that I can now hear from the exhaust when I shift at high RPMs sound really nice.  

Posted by: @dev

Posted by: @phats

You guys crack me up .... there's some sensitive dudes right there ....lol 

  In that case you are really gong to love my new out of focus pictures. It will certainly make you a sensitive irritated dude.  

 

 

 

Actually I like your last pic you posted , it wasn't blurred and I could see your garage floor needed repainted gray .  😀 

Nah ... I'm use to your blurry shots , it's all good .

Posted by: @phats

Posted by: @dev

Posted by: @phats

You guys crack me up .... there's some sensitive dudes right there ....lol 

  In that case you are really gong to love my new out of focus pictures. It will certainly make you a sensitive irritated dude.  

 

 

 

Actually I like your last pic you posted , it wasn't blurred and I could see your garage floor needed repainted gray .  😀 

Nah ... I'm use to your blurry shots , it's all good .

    It was a crappy cell phone picture which does the job. For scientific photography or how to do books thats when everything has to be in focus. You were use to my previous 35mm shots then my new medium format camera is on another level of blurry with bokeh balls that Im finding is too much. 

Posted by: @phats

You guys crack me up .... there's some sensitive dudes right there ....lol 

With n.a. just about all you do apart from bolting on a free breathing exhaust is going to be marginal. Even thén some will only notice the extra noise because yes, there are both more sensitive and less sensitive drivers. Some will notice 0.1 bar more in the front tyres others would not notice 0.5 bar extra.

I would very much lóve to drive a stock OEM car now.  I have done several marginal gains mods. and the pitt fall is that you get used to it all. Hardly any ZZW30s over here though. Only a handful for sale in whole state and none near so canñt even do a pretend test ride. Still high on the agenda though to calibrate my mod. sensitivity.

I installed my Toyota, Litens-made, OAD yesterday. I took the car out and I didn’t notice anything immediately. I’m still getting used to my IACV working properly. I was still curious about why between shifts my idle would drop quickly then bounce back 1-200 RPM.

I believe it was the alternator dragging the engine speed down between shifts. With the OAD, the drop off between shifts is slower and there is no recovery bounce. The OAD clutch engages, lessening the drag on the motor from the alternator. I’m liking that. I’m thinking this should be an absolute necessity with ultra light flywheels.