View Full Version : Question, does the Ap-SCTC-130 pulley unbalance the crank?


TrevorS
02-19-2008, 06:24 AM
I'm told by Agency Power this pulley is an appropriate replacement for the xb2 oem crank pulley. My question is whether it provides the same counterbalancing effect (assuming there is one) as the original stock pulley that weighs significantly more. Anyone know the answer to this question?

http://www.agency-power.com/catalog/product_info.php/products_id/136

Thanks -- Trevor :)

NurSpec
02-19-2008, 09:37 PM
The pulley is balanced itself. They have sold over a thousand of them with no customer complaints or returns. It does not unbalance the crank. However, this pulley and other after market pulleys like it do not have dampeners.

TrevorS
02-19-2008, 10:02 PM
The pulley is balanced itself. They have sold over a thousand of them with no customer complaints or returns. It does not unbalance the crank. However, this pulley and other after market pulleys like it do not have dampeners.

Thanks! Does that mean the stock pulley includes a vibration damper? Their ad says this pulley is 3.5lbs lighter -- are you suggesting at least some of that additional weight is beneficial to the welfare of the engine?

whitebreadbox
02-21-2008, 12:48 AM
the stock pulley does not have a damper built in, like those on old V8's. the engine is internally balanced. its cheaper for a company to mass produce solid pulley's than lightweight aluminum ones. i've been running the NST set up for the last 10,000mi and have had no issues other than much better response (faster rev-up) and a little fuel savings. and any research you do on lightweight pulley's will produce the same results. hope this helps.

TrevorS
02-21-2008, 04:22 PM
Sounds good, and thanks for the information! I tried peering around the pulley end of the engine and it looks extremely cramped down there. How does one go about changing pulley's?

whitebreadbox
02-21-2008, 10:19 PM
pop off the front pass tire and undo the plastic pop clips that hold the black plastic cover on. you'll see the pulley from there. you'll need an impact wrench to get the crank pulley bolt out. and a 19mm socket to use on the belt tensioner to free enough slack to get it off the crank pulley. i used a 3 jaw puller but have heard that you can pull the pulley off by hand. then, just slide the pulley (with alignment key) back on the crank. put the belt back on, install the panel and put tire back on. REMEMBER the belt routing before taking it off. hope this helps

TrevorS
02-21-2008, 11:28 PM
That's great -- sounds like it may be a worthwhile $140 mod :)!

whitebreadbox
02-22-2008, 10:39 PM
not to sway you, but i'm running NST pulley's and would tell you to go thru them. a great product and cheaper than the one you mentioned. just my opinion. just thought i'd throw it out there.

http://www.nonstoptuning.com/pKitToySciXB.htm

TrevorS
02-22-2008, 11:16 PM
Thanks for the suggestion, unfortunately I've already placed an order for $141 shipped -- no question, cheaper would have been nicer :).

whitebreadbox
02-23-2008, 02:57 PM
i hope the install goes easy for you and that you can put some pix up. enjoy it!!!

TrevorS
02-23-2008, 08:55 PM
Thanks -- I'm hoping to combine it with my Eibach Pro-Kit install next week, but that can't happen until the strut spring compressor and crank pulley actually arrive -- hopefully by Wednesday (then I have to cross my fingers on the weather.) Some companies are really quick to turn around parts, but others seem to really take their time :(!

TrevorS
03-02-2008, 06:00 PM
the stock pulley does not have a damper built in, like those on old V8's. the engine is internally balanced. its cheaper for a company to mass produce solid pulley's than lightweight aluminum ones. i've been running the NST set up for the last 10,000mi and have had no issues other than much better response (faster rev-up) and a little fuel savings. and any research you do on lightweight pulley's will produce the same results. hope this helps.

Unfortunately, the stock "pulley" IS in fact a torsional harmonic vibration damper. I've been trying to investigate this through a thread in the tC forum and I just found a photo today in ClubXB's DIY section that clearly proves it. Here it is:

http://i8.photobucket.com/albums/a33/TrevorSt/xBpulley.jpg

I placed an order for an Agency Power crank pulley a week ago based on your assertion -- however, it's now apparent to me you're incorrect.

Here is my thread in the tC forum. A lot of information is accessable through it:
http://www.scionlife.com/forums/viewtopic.php?t=213108

My aluminum pulley arrives Tuesday -- now I have to decide if I'm actually going to install it.

whitebreadbox
03-03-2008, 03:18 PM
after reading the above link and looking at my stock pulley, it does have a rubber damper in it. I STAND CORRECTED and am sorry if i misled you in any way. however, i'm very happy with this mod and would still recommend it to anyone. BUT, its your engine and it will be your bill if anything were to go wrong with installing an aftermarket pulley. again, sorry.

NoLimitzBuilt
03-03-2008, 04:17 PM
I have been using the NST pulley for over a couple months now and no issues at all either. I have used a AP one in the past on my tC. This was before I knew about NST. It is a fairly easy thing to change. Takes about a hour total.

TrevorS
03-03-2008, 10:23 PM
I have been using the NST pulley for over a couple months now and no issues at all either. I have used a AP one in the past on my tC. This was before I knew about NST. It is a fairly easy thing to change. Takes about a hour total.

By any chance, are you (or anyone else) aware of any reports of someone doing a 2AZ-FE tear down after 50K+ miles with one of these pulleys and inspecting the crank bearings?

THansenite
03-11-2008, 03:31 PM
There are people with NST pulleys on that have been running strong for over 100,000 miles. There is a thin rubber strip around the stock pulley, but these reduce very little vibration and the rubber quickly degrades because of the conditions present near the engine. I have yet to see anyone report damage to an engine as a result of putting on a lightweight pulley.

I have actually chatted with Mike at NST about the facts behind the lightweight pulleys and their impact on our engines. He presented me with overwhelming factual information from both him as well as third-parties that have done extensive testing on this subject with no ill-effects.

Chrio
03-20-2008, 05:09 PM
I want to do this too. BUt I don't want to ruin my waranty.

DREWxB08
08-08-2008, 12:55 PM
I have one sitting in my Room Got it from my friend who replaced it with the NST kit for his tC. i wanna use it but im still not sure if i should put a used pulley on? I mean cant reali make much of a differemce. I keep saying i wanna install it but never do.