yes or no on lightweight crank pulley?

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Bheinen74
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yes or no on lightweight crank pulley?

Post by Bheinen74 »

anybody running a lightweight crank pulley?
for a long time mileage-wise?
what is the damage to consider? (bearings go out, crankprobs, etc etc.)
thanks
they go for like 120.00 is that money well spent or not. saves like 4pounds rotation weight what does this equate to for a rather stock ej22t
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jefferson
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Post by jefferson »

I haven't had mine on for that long so can't say about long term problems. I forsee nothing happening. I would get an underdrive pulley as that is where most of your horsepower gain will come from. Lighter weight will let the engine rev a little quicker, but makes no more horsepower. I would really like to have it explained to me how putting a lighter pulley on makes horsepower. The underdrive pulley actually frees up horsepower to be used for propulsion rather than driving the accessories. I used the Unorthodox Racing pulley and the only problem I had was one of the belts they recommended didn't work and I had to come up with something else. Not really a problem except I made it a problem by tearing up the adjustment bolt trying to get a too long belt tight. I think I wrote down what belt I had to use if you go that route. It made a noticeable difference. I posted a review in this section.

Jeff
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evolutionmovement
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Post by evolutionmovement »

The theory of the lighter pulley is that it is less mass to spin, akin to a lighter flywheel, but I think the benefit is minimal. Rather than underdriving accesories, what about just rigging an alternator switch like a kickdown relay so that it doesn't charge during acceleration during acceleration. An underdriven steering pump (especially an old one) might get annoying during quick maneuvers.
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BAC5.2
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Post by BAC5.2 »

Steve, the ECU already does that I believe. The AC compressor and the Alternator deactivate under WOT. I know the AC compressor turns off on WRX's at least. Run on the dyno with the AC on and with it off, and you get the same numbers.
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Post by Legacy777 »

Yeah, the AC turns off under WOT.

I'm running a lightweight crank pulley. I like it....and have been running a varient of lw & underdriven and just lw since 98 or 99.
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evolutionmovement
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Post by evolutionmovement »

I know the A/C does, but I'm not sure about the alternator. I had thought they did, but I'm reading stuff about 'intelligent alternators' lately that are only supposed to run during cruise and keep better tabs on the battery so as to not run at all if it doesn't need to so I'm wondering now.
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Adam West
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Post by Adam West »

Over a year running without problems -just make sure you have them tiigtened to factor spec b/c they've been know to come loose and that's not good - no AC - I get 1-2 mpg better - don't reallly notice a huge difference in quicker reving but perhaps a bit...If you can get one cheap go for it.
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SP-Boxer
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Post by SP-Boxer »

Only the crankpulley isn't something you will notice, but together with your alternator pulley and steeringpump pulley, it works better.
You can see it like a light flywheel, but than a few times smaller :!:

There is nog gain, but you lose less power. So at the wheels, there is more left :wink:
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Psychoreo
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Post by Psychoreo »

just make sure you have a good way to torque it down. Some threadlocker won't hurt either... I had my GFB LW fall off while driving because I couldn't get it torqued properly :?

Good thing there was no damage :D
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Post by Lusus3 »

Sorry for dipping into this but you guys made me think iof something.

is there a higher output alternator that swaps right into a 91 SS? Like does one from a WRX work (and is an upgrade)

If so is anyone currently doing this that you know of? Im thinking of going underdrive but really dont like the negative effects of such. Thats why I used an FD alt on my FC when I had it.

Sorry if this seems like a hijack. Just occured to me.
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jefferson
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Post by jefferson »

I haven't experienced any negative effects of going underdriven. The only problem I could see would be if you had a high draw on your electical system. Mine is all stock. I don't have any of that anti-performance stereo stuff on mine. It just adds weight and drag on the engine trying to run it.

It did seem that the ac didn't cool as well as I thought it should around town, but once you got up to some steady speed it worked great. I did do a good cleaning on the ac coil under the dash. It had alot of leaves and other detritus that was plugging parts of it up. It has to work better now whether I notice it or not.

Jeff
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Post by 93forestpearl »

I don't believe, from staring at hte wiring diagrams for our cars for hours, that the alternator is controlled by the ECU. Its an independent system. The AC on the other hand does turn off.
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