lighten flywheel

B

bigguy

Member
I here that youshould not use a lighten flywhee whith out a counterblance crank. Can someone please shine some light on this as i don't understand if the flywheel is balanced what the deal is.
 
A lightened flywheel is for the benefit of acceleration.
A counterweighted crank is for the benefit of the main bearings.

You can go with either one by itself, or both together.
My personal first choice would be to add counterweights.
 
In the fifties I used a flywheel with 15 pounds removed and no balance with a stock A crank and babbitt. No problems.
 
Just how light are you thinking of going? Specialty Motor Cams (Wisconsin) has a 25 pound aluminum flywheel with a cast iron insert. That's pretty light. It could help your car go up the hill (from stopped) PDQ. On the other hand, an ABBH (As Built By Henry) flywheel provide enough rotating mass to whizz up that hill without pouring on the fossil fuel. Just run the stop sign at the bottom and coast on up.
I have one counterbalanced engine with a lightened flywheel and one stock-cranked engine with a lightened (just enough lip cut off to bolt on the V8 pressure plate) flywheel. The first one's in an open truck and the second's in a Roadster. It probably is no surprise to you, but they both go up the hill PDQ -- from stop or on the roll. I kind of like the Jenny Craig flywheels, especially when I'm laying on my back under the car trying to hang it on the crankshaft. I am not a fan of the Twiggy version because I enjoy using that kinetic energy.
I learned the hard way that the most effective way to smooth out the engine was to adjust the valves. If you have an exhaust valve that's not opening very much, the engine will be pretty sluggish no matter how heavy your flywheel is.
This is an IMHO opinion. Aren't they all?
 
I think 20 lbs. lighter than stock is the plan someone sent me a number of years ago will brake out the print to see what the difference was suppose to be. thanks for the advise dont want to do an overhaul with a new crank at this time. but will check clearances for crank and rods before install new flywheel.
 
i have 20#s off my flywheel . no big difference , but its all balanced ........ steve
 
I seem to remember reading that one of the reasons why the flywheel was weighty was to counteract the unbalanced engine and help cut down on the vibration.

Not having the worlds largest amount of horsepower the flywheel weight also helps here. Have you ever been to a show where they have the old farm equipment or pumps that only fire every fourth turn, its the weight of the flywheel that keeps the momentum going.

What excess stuff are ya carrying in the trunk, maybe have a clean out there to loose the weight, just a thought:)
 
If everybody I sell lightened flywheels to have a balanced/flyweighted crank, there are a lot of balanced/flyweighted cranks out there and I wouldn't expect to sell any but, I do. There is no reason to run the original flywheel as is if you want a lightened one. I believe in the early days people were so unused to using a clutch, Ford made the flywheel heavy so the pedal could be just dropped and not kill the motor and take off. Just remember, the T had a semi automatic transmission and did not use a clutch pedal.
 
You must log in or register to reply here.
Back
Top