We balanced both BMW M52 assemblies here to under a tenth of a gram end to end. Jay’s was .08/.08 and Clarks was .09/.07 Anything under .5 gram is considered balanced on a performance level for reference.
Jay’s UUC LWFW was off quite a bit. 43 grams had to be removed. even Clarks JBR which was rebuilt and said to have been balanced by the company, turned out to be ~10 grams or so off. Could just be that their FW balancer register was off .001" from the actual crank, and that would create the offset. It’s why we balance rotating assemblies as complete assemblies, harmonic balancer to FW, because you can’t go by some other balancing effort from separate parts on other machines.
Yeah that’s a little extreme right there, but you’re thought is correct. It’s all a basis of where the off-balance is located on the rotating assembly, and the total mass of the rotating assembly. 3 grams off near a main journal isn’t the same as 3 grams off on the outer diameter of the FW, nor is it the same between a rotating assembly of 100lbs or 40lbs
On very high rpm engines I like to do internal balancing, then external balancing(FW, harmonic balancer, etc) that way if components were ever damaged and needed replacing, you can just dynamically balance the new parts and install them w/o having to tear down the entire engine to balance the bottom end as a whole.
yup circles act weird when they are spinning, if there is extra weight at a point close to the center of the flywheel when the flywheel is spinning at XXX RPM’s the circumference of the circle that the unbalanced weight is traveling upon is close to the center of the flywheel and is quite small. So even though the extra weight is spinning at the same RPM’s as the outer portion of the flywheel it is traveling a much shorter distance per revolution creating less centripital (sp?) force than say extra weight that would be located on the outside of the flywheel traveling more distance per revolution meaning the outside of the flywheel is traveling faster than the inside material of the wheel. This means the outside weight would be traveling at a faster velocity. Basically what I am getting at is a little unbalanced weight with its center of mass located near the inner portions of the flywheel would cause less of an unbalanced feel than that same amount of unbalanced weight with a center of mass located near the outer perimeter of the flywheel.
To demonstrate tape a couple quarters or something near the center of a frisbee and try to spin it on your finger, it shoudnt be too hard. Now tape that same amount of weight near the outer edge of a frisbee and try to spin it on your finger it will prove to be more difficult.
Stock flywheel refinished and balanced by BoxerSix on my STI…I prefer OE flywheels over aluminum (esp in Suby) because the knock sensors are so god damn sensative to noise.
i was drinkin at time of post :lol i didnt mean 200 lbs i meant 20 but thats what happens when i slam the keyboard .it was a while ago i read it and all the circumstances so it may be flaued a little;)
I have never used clutchmasters brand before so to me that doesnt mean much. My friend got a fidanza that did not fit onto the crank snout and rather then exchange it they told him to sand it down. Unfortunately it was off pretty far… I also had one on my car and the steel friction plate warped like crazy.
I stick with steel/chromoly flywheels, never been happy with any aluminum ones I have used before.
Strange stuff. I’ve never heard a single negative comment about Clutchmasters or Fidanza products in the past 10 years until now. It’s usually just a bunch of people saying they hate their products but have never used their products before. I never put a second thought into getting mine balanced until now, it’s only a few bucks so it’s definately worth the piece of mind.
I’ve had pretty poor luck with Clutchmasters products, both in my own cars and customers alike. I just don’t use them now. I’ve also experienced near exact issues as Paul did with Fidanza with non fitting flywheels and BS remedy suggestions from the company. :wierd The only aluminum FW’s I use now are the 930-993 KEP single mass replacements, other than that it’s steel or nothing.
when balancing the flywheel make sure you do the pressure plate to. My stock resurfaced flywheel with the dxd pressure plate bolted to it was 7 grams out of balance
