Since the above link to my BalanceMaster results is no longer active, and because I've had several folks ask, here is my experience and comments from 2014, for what it's worth, with some recent edits:
I have completed a test of the Balancemaster prop balance product on my AFP vertical injection, ECI 360, with Whirlwind RV200 prop, on my RV-7A with 380 hours.
First, thanks to Roger Lee, and A.J. Pawloski, for their great help in conducting this test. The Balance Master product may be obtained from Mark at Checkered Flag Restorations, (
http://www.checkeredflagrestorations.com/distributors.html).
The following results were done with ACES equipment and prop at takeoff pitch (ie. fine pitch with RPMs controlled by the throttle).
First we completed a new conventional balance just prior to installing the Balancemaster. The results:
Without conventional balance weights at 2300 rpm: 0.17 ips.
After a new conventional balance at 2300 rpm: 0.12 ips.
Next, we removed the conventional balance weights and installed the Balance Master. The results:
2300 rpm: 0.11 ips.
2000 rpm: 0.11 ips.
1500 rpm: 0.11 ips.
1000 rpm: 0.11 ips.
Results and Comments:
1. The cost of the Balance Master, at $350 (not including costs associated with prop removal and re-installation), was over twice what it cost me to get a conventional balance ($125).
2. Unlike a conventional balance, installation of the Balance Master requires removal and re-installation of the propeller.
3. Except for prop removal and installation, installation of the Balance Master was very easy. It fits directly on the front face of the ring gear flywheel. Existing propeller bolts were able to be reused.
4. Since I have a lightweight propeller, the added weight of the Balance Master (about 1.3 lbs) was not a concern for me.
5. Looking only at the vibration numbers, the Balance Master (0.11 ips) did not appear to be significantly better than a conventional balance (0.12 ips).
6. Notice the consistent vibration numbers at each rpm. This is one of the reported advantages of the Balance Master.
7. Unlike a conventional balance, use of the Balance Master should not require a re-balance every few years.
8. Though not listed here, the differences in vibration levels at various rpm's with the conventional balance was no more than 0.03 ips. I don't claim to be able to 'feel' differences this small, however, as soon as I started the engine with the Balance Master product, I did 'intuitively believe' that the prop/engine was smoother. Attribute that to wishful thinking if you will.
9. I was never completely confident in these test numbers. I would like to see results from additional testing.
Should I keep the Balance Master or return to the conventional method? I look forward to your comments.
About a month later, I returned the Balancemaster and completed another conventional balance with a different person doing the balancing. The results, at 2300 rpm were:
without any balance weights, 0.66 ips
after conventional balance, 0.02 ips.