408W Rotating Assy Balance

[js66coupe]

It's my understanding that the 351W uses an external balance weight to balance the rotating assy. I am seriously considering having the rotating assy. internally balanced so I don't have to run external balance weights. Has anyone here done this? TIA

 

[rbohm]

yes it has been done, and there are even flywheels and balancers that you can buy that are for zero balanced engines.

 

[j69302]

is there a benefit to having a internal balance assembly vs external?

 

[rbohm]

is there a benefit to having a internal balance assembly vs external?

not really. the weight of the rotating assembly comes out the same either way, though some will say that an internal balanced engine will run slightly smoother, but the reality is that unless you are going racing at the highest level, an external balanced engine is going to feel and work just like an internally balanced engine, and both will last as long as the other will.

 

[BuckeyeDemon]

if you're planning on getting a new damper, flywheel and forged crank then go internal. if you have a cast crank then don't even consider it.

 

[mycoses]

Internal balance allows you to replace the flywheel and balancer(neutral balance) anytime without the need to rebalance the engine. Also precludes the need to deliver the flywheel and balancer to the engine builder when the engine is being assembled.

 

[65coupe408w]

my 408w is zero balance. I have no regrets about having this done. I feel the motor revs up extremley quickly which is likely helped by the lack of a counter weight on the flywheel.

 

[Wicked65]

Id go with what 65 Coupe said. If you really want to see a difference, do a zero balence. But really, id take a look at what your going to be doing with the motor to see if that extra money is even worth it. later model 351's are all 28oz already. and honestly, mine revs pretty damn quick.

 

[blown65]

not really. the weight of the rotating assembly comes out the same either way, though some will say that an internal balanced engine will run slightly smoother, but the reality is that unless you are going racing at the highest level, an external balanced engine is going to feel and work just like an internally balanced engine, and both will last as long as the other will.

Going to pretty much agree with this. No reason to internally balance a street motor IMO. Turning some high revs then ya, definitely go internal.

Internal balancing can get pretty spendy if your crank is needing heavy metal.