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ZPI Lightweight Crank Pulley

41869 Views 276 Replies 63 Participants Last post by  bhs13475
http://www.thescionstore.com/Merchant2/mer...Category_Code=E

Does anybody have any thoughts on this? It's the same diameter as stock, so it isn't an underdrive pulley, but they claim it weighs less than 25% as much as the stock pulley (1lb vs. 4.4lbs)
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Don't do it. Ask Steve Dinan or Reg Riemer why not, they're both very well known tuners (know way more than I do). Wait for ATI, Fluidamper, or TCI to develop a proper torsional vibration damper. Removing the OEM piece could have very detrimental consequences especially since we have a chain driven oil pump.
Fair enough. Thanks, Lance.
i have the unorthodox racing pulley, works great for me, its so light, it wouldnt even show up on a scale. the original is like a freakin lead paperweight. big difference. one of the benifits of using the unorthodox racing pulley is that you can use the stock belt. the pulley is the exact same size as the original but as heavy as a paperclip. i would take a pic for you if i could angle my cam to the side but its not worth the effort. i think the pulley cost somewhere around 200 bucks..
Originally posted by NavyDoc05@Oct 8 2005, 03:54 PM
i have the unorthodox racing pulley, works great for me, its so light, it wouldnt even show up on a scale. the original is like a freakin lead paperweight. big difference. one of the benifits of using the unorthodox racing pulley is that you can use the stock belt. the pulley is the exact same size as the original but as heavy as a paperclip. i would take a pic for you if i could angle my cam to the side but its not worth the effort. i think the pulley cost somewhere around 200 bucks..
Notice any differences?

-Ed
Originally posted by NavyDoc05@Oct 8 2005, 03:54 PM
i have the unorthodox racing pulley, works great for me, its so light, it wouldnt even show up on a scale. the original is like a freakin lead paperweight. big difference.
Huge difference. You removed a torsional damper and replaced it with a paperweight. Call us when the chain on your oil pump breaks from the effects of torsional vibration.

If you really had an interest in reducing rotating mass, you should have got in on the Fidanza buy. There's no risk of engine damage from a lightweight flywheel. There are a number of documented cases of engine damage from replacing torsional vibration dampers with solid pulleys. I'll be happy to name their names too.
Originally posted by lo bux racer@Oct 7 2005, 08:56 AM
Don't do it. Ask Steve Dinan or Reg Riemer why not, they're both very well known tuners (know way more than I do). Wait for ATI, Fluidamper, or TCI to develop a proper torsional vibration damper. Removing the OEM piece could have very detrimental consequences especially since we have a chain driven oil pump.
i was thinking something along those lines when i saw the ad for the unorthodox racing pulley. glad to know that, while i didnt know what i was thinking exactly, i was thinking around the same lines. dont get me wrong, i am a fan of reducing the rotating mass, but i would insist on it being done with the proper parts. hence, i run the fidanza flywheel for now, and will wait for the proper damper.

i like oil circulating through my engine.
eddnog, yea man i noticed a difference. especially in throttle response, or at least it feels. LO BUX RACER, where did you get your information? do you have a website address from a credible author?if so send me the link please. and yes my oil pump still works, and if im supposed to feel vibration, i havent felt it at all.

i just got off the phone with my personal mechanic, ESC racing, www.escracing.com, and he says he has never heard of a lightweight pulley causing any problems of that sort, and even if it did, why would Unorthodox Racing make a faulty pulley? that opens them up to all sorts of lawsuits. my mechanic is going to call unorthodox racing on monday to see what they say, and im sure it will be the same as his.. overall, im still happy with my buy. fidanza flywheel? why would i do that? if im going to do that im going to get a new clutch as well. sorry, my car is still fairly new.
Why would you need a new clutch at the same time you replace the flywheel?

Anyway, I'm going to leave the rest of your post for Lance. Congratulations on the new ####### he's going to give you.
lol
Originally posted by Zygote55@Oct 9 2005, 11:48 AM
Why would you need a new clutch at the same time you replace the flywheel?

Anyway, I'm going to leave the rest of your post for Lance. Congratulations on the new ####### he's going to give you.
I had to think about that one for a second...

Lol. It's so true. I've got a shiny new #######!
I just got the ZPI pulley, havent installed it yet, but about what lo bux racer said, i will ask my uncle, who is a mechanic before he installs it
Originally posted by NavyDoc05@Oct 9 2005, 08:46 AM
eddnog, yea man i noticed a difference. especially in throttle response, or at least it feels. LO BUX RACER, where did you get your information? do you have a website address from a credible author?if so send me the link please. and yes my oil pump still works, and if im supposed to feel vibration, i havent felt it at all.

i just got off the phone with my personal mechanic, ESC racing, www.escracing.com, and he says he has never heard of a lightweight pulley causing any problems of that sort, and even if it did, why would Unorthodox Racing make a faulty pulley? that opens them up to all sorts of lawsuits. my mechanic is going to call unorthodox racing on monday to see what they say, and im sure it will be the same as his.. overall, im still happy with my buy. fidanza flywheel? why would i do that? if im going to do that im going to get a new clutch as well. sorry, my car is still fairly new.
Start here. Then click here. Then click here for information directly from Toyota, the guys who designed your car and engine.

Shawn Baumgartner (owner of Unorthodox Racing) will NEVER tell you there is any danger to his product. I have argued with him in the past about this, he is an idiot. He also will not pay for your engine repairs, he only warrants his crank pulley for manufacturing defects. He does NOT warrant any incidental or consequential damages, and has not paid any claims for damage attributed to his product because his warranty is very specific.

Ask Guillermo Polo, Michael Gaari, Lance at Toyomoto in Miami, and a host of other Supra owners what happens when you remove your harmonic damper and replace it with a UR pulley. Flexplate bolts back out. Crank position wheels break and rotate so the engine either won't start at all, or will fail intermittently while driving. Rod and main bearings show unusual wear patterns. And a host of other wonderful things.

I realize you don't understand the physics. Here's what I can tell you for sure: your oil pump is chain driven. Chains do not like shock loads. Removing the damper increases the shock loading on both the oil pump chain and the cam chain. One (or both) will break prematurely. If they were belt driven, it would be no issue, but they are not belt driven, so they will likely be the first casualties from removing the damper.

The flywheel change has NO negative effects. Zip. Zero. Nada. Nil. It will not void your warranty, but I guarantee you, the UR pulley will because Toyota will show up in court with the same documentation I've linked here and you'll be screwed. It is a BAD mod, and should not be recommended by any reputable engine builder. NO domestic engine builder would ever recommend removing a torsional damper and replacing it with a solid pulley. They know all too well what will happen to a cast crank without a damper: it will break, without any doubt. This is why Fluidamper, ATI, and TCI have a booming business with domestic engines. It is not only bad physics, but it is also bad business to replace a damper with a solid pulley.
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*cough* Pwned...?
from the motherf#cking top rope.
lmao from the topof the rope. thanks for the info, ill follow up on it, and if all else fails, ill put the stock one back on. ive only had the UR pulley on for a week so it cant be that bad yet. who knows. ill bring this up to my mech too, see what he says. thanks
I'd love to hear what ZPI has to say as well....too bad they don't visit this forum.
i went to my dealership today and spoke to one of the mechanics about the pulley, he said yes it does cause additional stress on the oil pump, no doubt, but that the chances of it breaking are like 1 in a million. he even asked me where i got it, he to owns a tC. he recommends it, not just the brand, but just replacing the part in general. im starting to get a little confused, im getting this stuff about it not working then it working. wtf
That mechanic hasn't been building engines for 25 years. I know plenty of line mechanics who couldn't even time cams if the factory didn't provide the magic marks for alignment. His statement about breaking the chain is horribly misinformed. I can point to manufacturers over the years making serious mistakes like this an suffering terribly because of it, starting with BMW motorcyles in the 60's breaking cam chains on their US models.

Ultimately it's your engine. I wouldn't risk it. It's not worth it, and the performance gain is minute compared to changing the flywheel (which takes nearly 7 lbs off the rotating assembly instead of 3 lbs and it is at a MUCH larger radius than the pulley.)
Is the extra 0.5HP worth the risk? If so, and you like replacing main bearings and oil pumps, then gopher it. Also, there are some detriments to the valvetrain for the torsional vibration. Basically you can throw the cams off at higher RPMs from the transmitted harmonic distrubance. It's been discuseed more than a few times, and basically it comes down to the engineers vs the salesmen. I wonder who wins that argument?
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