Balancing

[daveymc29]

How close do you balance your engines? Why do so many shops poo poo the importance of total balance, or as near to it as possible? What does real balancing cost and entail, including curing runout and wobble?

[Dodge]

I try to balance them until the needles don't move, zero out. But sometimes you keep chasing that last 2 grams and can't get it out. Costs very as some motors balance fairly quickly and some take for ever.
The range can be from about $200 to $600 with the average $200-$300
Some shops may poo poo it because they can't do it....

[Mike V. Florida]

It's a cost benefit thing.

From builders sites on the internet;

Stock long block $3300
Balanced long block $4650

That's 1350 more for a balanced engine.

Is the benefit of the additional money spent worth it for a car that will take your family for Ice Cream on Sundays?

How about a car that you intend to drive as a daily driver at prolonged speeds above 40-45 MPH.

Here is another question for everyone, How many of you have driven an A with an engine brought back to factory specifications and placed in a car that is also restored to original frame specifications? You see the original factory specifications call for everything to be balanced but did not have additional weights on the crank. I have spoken to those that have driven such an engine and tell me it is a smooth running engine with little to no vibration.

[Kevin in NJ]

There are few cars out there with untouch very low milage engines. The first thing noticed by people is how little vibrations the engines have.

It is extremely hard to get a modern engine balanced properly. The guys take short cuts and have poor quality control both in the grinding of the cranks and the overall process of building the engines. This is based on comments from the owner of the company that made crank grinders and my brothers experiences.

Ford precision ground the cranks and ensured the flywheels were less then .001" off center. Today less then .002" is considered good and I can show you one at .008".

Then the rods, during producition years, were made to a certain weight +-1 gram at each end. The whole rod piston units were further grouped so they would be in 4 grams total weight in the engine.

Keep in mind today babbitted rods are +- 5 grams total weight, supposedly.

If you want a good smooth engine you have to be anal about everything.
Remember, if you take the prints to a machinist and ask them to machine to them they will tell you two things. You want it built like a race car and No they will not do the work. Part of the reason they will not do the work is they do not have the equipment to do the work.

[captndan]

Sponsored Links (Register now to hide all advertisements)

Not sure what all the fuss is about balancing. I have had several engines balanced. You simply tear the engine down and take every moving part to a balancing company. This does not mean the local machine shop. Makes a world of difference if done correctly.