TOLL FREE  888-339-9009

 LOCALLY  360-435-1701




It's a Fact!
28 grams of unbalance
at 4" from center of rotating part
at 4,000 RPM causes a force of 112 lbs.

Don't let a few grams of weight shorten the life of your engine!

The chart below lists the amount of force applied to the main bearings of an engine with new pistons that are 7,14, and 28 grams heavier or lighter than the original pistons...

At 4"
2,000 RPM
4,000 RPM
6,000 RPM
8,000 RPM
7 grams
7 lbs.
28 lbs.
63 lbs.
112 lbs.
14 grams
14 lbs.
56 lbs.
126 lbs.
224 lbs.
28 grams
28 lbs.
112 lbs.
252 lbs.
448 lbs.


Perpetual Balance, LLC offers complete precision balancing of your rotating assemblies. We balance your crankshaft as a complete assembly with the harmonic damper and flywheel/flexplate installed on the crankshaft during the balancing operation; this is the most accurate method of precision balancing your engine. We can supply your harmonic balancer and flywheel/flexplate, or use your existing good condition harmonic damper and flywheel/flexplate. Precision balancing should also include correcting the weights of the pistons, as well as both the rotating and reciprocating ends of the rods to measure within 2 grams. Using the corrected weights, the bobweight is then calculated specifically for your unique rotating assembly.

Street or Average

Street or Average balancing does not include correcting the weights of the pistons and rods. Only the crankshaft is balanced. Internally balanced engines are frequently balanced without the harmonic damper or flywheel/flexplate installed on the crankshaft during the balancing operation. Externally balanced engines may use a harmonic damper and flywheel/flexplate from the engine family, not necessarily the assembly that is going to be used on your engine. All parts including harmonic dampers and flywheels/flexplates have tolerances. The only way to precision balance your engine is to use the parts that will be assembled with the engine while balancing.

Most factory engines are produced on assembly lines where the parts are not balanced as match assembly. Each individual part – harmonic damper, flywheel/flexplate, and each end of the crankshaft – has a tolerance of as much as much as +/-  14.0 grams.

Any unbalanced condition results in vibration and shortened engine life. Perpetual Balance, LLC offers custom precision balancing that measures within 2 grams!

Precision vs. Street Balancing

Your Engine Balancing Specialists Since 1985

Perpetual Balance, LLC

Call Us Toll Free: 888-339-9009

or Locally: (360)435-1701

Your Engine Balancing Specialists Since 1985