Re: engine balance

Posted by Tim Cole On 2015/10/25 5:42:57

I think neither PackardV8 nor Motiv8 are contributing anything positive to this discussion.

Motiv8 says Packard motors are no good and that he knows better than them how to build motors. I don't think he has any engineering background because if he did he would demonstrate the balancing formulas for an engine and then show mathematically why they should be ignored.

PackardV8 insists that motor rebuilding is a basement operation which denigrates people who have the qualifications to speak knowledgably on the subject.

While I don't think that Packards are the best thing that every rolled down the highway, I have driven low mileage examples and found them to be impressive performers. Back in the 60's and 70's they drove better than many a brand new car.

However, wear and tear has taken a toll on the machinery and it exhibits the faults of being worn out. Thus, enthusiasts have to make due with suboptimal results.

People familiar with my advice know that I try not to be condescending because the intention here is to help people with their cars. If it's mathematics and technical discussions you want that can be done somewhere else. I can fill the trunk of my car with authoritative journals and I can spread them out on a table and you can declare they mean nothing. But this discussion not the appropriate place for such.

To aid in the point I am trying to impress consider the following balancing formula:

Rotating Weight
* Big end of rod (including fastening hardware)
* Bearing
* Oil (normally estimated at four grams)

Reciprocating Weight
* Piston
* Wristpin
* Pin locks (if used)
* Small end of rod
* Piston rings

Bob weight = Rotating Weight + (Reciprocating Weight x .50)

The bob weight is a model weight bolted to the crank to simulate the operation of the motor. Suppose the Packard company was using a different formula based on the results of trials at the proving ground? Suppose after running a Packard 8 25,000 miles at full throttle they found the motor would benefit from a proprietary formula? If you don't have the required specifications then even the best attempts at rebuilding will yield sub-optimal results.

To claim their motors are junk based on results gathered from using the wrong specifications is non-sense.