ZX harmonic balancer options

[Matthew Abate]

 

Hey guys,

You may know that I am building a ZX motor for my 240z with a euro SU carburetor configuration, but I am stumbling over the harmonic balancer I should use here. I've read about thirty threads on this topic, from the 5 or 6 forums that I follow, and none of them is actually comparing the options against each other.

I only need one pulley, so I had initially intended to go with a standard 240z balancer, and if I could find one from Europe with just one pulley, even better. However, I've read in a lot of places that the factory balancers are prone to failure. I don't plan to hang out in the high revs all day long, but I'll definitely be getting into them periodically and I don't want my balancer flying apart.

I also read somewhere that the timing marks from my '83 ZXT engine aren't in the same location as 240z timing marks, so I have to use something meant to go on a ZX.

So now to my actual question: has anyone done a comparison of the various option for balancers?

Snooping around the internet yields three basic options: a factory balancer, the Powerforce balancer on MSA, or the $350-$500 options like ATI, BHJ, and Kameari.

I can't imagine that a street car should be running a $500 balancer, so I guess what I want to know first is are the two Powerforce balancers high quality (like Motorsport claims they are) or do they fly apart all the time like people on Hybridz are claiming?

Right now I'm leaning toward one of these, but if they are crap, or if there's a brand out there with something sub-$150, I'd love to know before I buy something.

 

Edited January 27, 2017 by Matthew Abate

[Matthew Abate]

To add some clarity to the discussion and perhaps help some other people with this, here are the options for a street application I have identified so far:

OEM by price

• '82-83 280ZX Turbo Factory Crankshaft Pulley ($259.87 @ Motorsport!)
• '75-83 280Z/ZX Factory Crankshaft Pulley (Double Pulley, $219.00 @ Z Car Depot)
• '73-74 240Z Factory Harmonic Balancer, US-Spec ($274.95 @ Motorsport!)
• 240Z  Factory Harmonic Balancer, Rest-of-World (NLA)
• Nismo L-Series Harmonic Damper (NLA)

Street Aftermarket by price

• Professional Products PowerForce Harmonic Dampers, 70-83 Z/ZX (Single Pulley, $105.95 @ Motorsport!)
• PowerBond Premium OEM Replacement Harmonic Balancers (Double Pulley, $183.97 @ Summit Racing)
• Powerforce SFI-Spec Racing Damper, 70-83 Z/ZX (Single Pulley, $199.95 @ Motorsport!) - Note that I have read threads about these being too small and not fitting, but this is 10-12 year old information and may have been rectified by now.
• Pioneer Balancers DA-41(Double Pulley, $249.97 @ Summit Racing)
• ATI Super Damper Sport Compact Harmonic Balancers ($359.97 @ Summit Racing)
• BHJ Dynamics Street Performance Special L-Series Datsun Harmonic Damper ($497.00 @ BHJ)

Racing Aftermarket by price (for posterity)

• Kameari L-Type Super Racing Damper Pulley ($382.40 @ RHD)
• BHJ Dynamics Race Special L-Series Datsun Harmonic Damper ($497.00 @ BHJ)
• Kameari L-Type Super Racing Damper Pulley Full Kit ($637... @ RHD)

I have also read that the Nissan Quest, Maxima, Laurel, and Cendric pulleys/ballancers will work, but I don't know if they require modification, nor if the timing marks are the same.

Another wrinkle is the 280ZXs that came with factory installed AC had the timing indicator on the passenger side (light) rather than the driver side (left). I'm not sure if that means the balancer is different, or if it means timing was maintained by aligning gear teeth differently.

Edited January 30, 2017 by Matthew Abate

[nix240z]

I guess it depends if your car is going to be a trailer queen or you will be hot dogging  it into the 7500+ rpm range.

if 7500+ rpm is your deal then go with something that should not fail, this is what Dave Rebello told me. 

If a trailer queen then i would go factory.

So I went with the BHJ race special L-series when Rebello built my 3.2L 

 

[Matthew Abate]

I feel like maybe there's an in-between way to use one's car, no?


Sent from my iPhone using Classic Zcar Club mobile

[nix240z]

just go with what your budget allows...

I went with the $500 damper because what is another $500 on a $10,000 motor..... 

[Matthew Abate]

So I'm taking that to mean that, in normal street driving conditions, the factory balancers are not crap as people have said.

[nix240z]

1 hour ago, Matthew Abate said:

So I'm taking that to mean that, in normal street driving conditions, the factory balancers are not crap as people have said.

that is correct, it is the super high rpm that cause the failures.  I still have an original on my other motor.

no need to put a $500 damper on a $2000 engine....

[ksechler]

This is what I use...

https://datsunspirit.com/shop/ati-harmonic-damper-kit/

Be careful what you use.  I think you need a special bolt or something to make it work.  

[Matthew Abate]

If anyone can comment on the ease of install and the performance of any of these it would be helpful for anyone coming along later to solve this problem. In particular, I think I've read that some of these are really hard to install because of tolerances, although I'm not certain they were certain they had the right version of the part.


Sent from my iPhone using Classic Zcar Club mobile

[Captain Obvious]

Not sure this adds anything to the discussion, but I once cut up a stock pulley/dampers on my lathe to reduce the number of pulleys. I was just messing around at the time, but if you were concerned with the accuracy (I wasn't), it wouldn't add a lot of time.

Here's a pic:

More pics and some details here:
http://www.classiczcars.com/topic/50727-a-project-is-brewing/?page=2#comment-46928

 

Edited January 29, 2017 by Captain Obvious

[RS02]

I was wondering about the same problem! I'm rebuilding my l28 for street use. I want to go for the double pulley power bond. I guess we'll find out if it works.


Sent from my iPhone using Classic Zcar Club mobile

[Namerow]

Thanks for the vendor and pricing research and the excellent documentation.  I'm dealing with the same question, so your efforts here have provided a great reference piece.

Don't forget the option of having your harmonic balancer rebuilt.  Dale Manufacturing (Salem, Oregon -- same town as as ZTherapy) offer a rebuild service at $115 (plus 2-way shipping) based on you supplying your core for them to refurbish.  There's also Damper Doctor in Redmond, CA (not sure about their pricing, but they'll send you a quote if you ask).