Is there another way of balancing a crank other than using Mallory metal? I have some new lite weight pistons and rods and thought that lightening the crank itself is a better option. Throwing a bunch of balancing weight on a 7K+ crank, it thought was a no-no.

Most of the shops I have used can and do reduce the diameter of the counterweights in a lathe when they can.
My latest all aluminum bracket motor, KB aluminum wedge water block with B1 heads and sheet metal tunnel ram with two E85 Marl Sullens converter Dominators and a used old KB 4.500 stroke top fuel fully counterweighted crankshaft ended up needing a BUNCH of heavy metal due to me using lighter Steel H beam 7.1 rods with Mopar Rod journal sizes and a set of light weight racing pistons to get it to balance correctly .
The price for that heavy metal is horribly high
I have had several Mopar and other brand 4.100 stroke cranks with the stock Mopar size (3.375) rod journal offset ground on the rods to increase the stroke to both 4.250 stroke and 4.30 stroke using BB Chevy 2.200 size, I also like having the mains turn down to B motor stock size and cut the counterweights down to clear the 400 B motor blocks, usually no heavy metal needed on them using both 6.700 and 6.800 long BB Chevy style steel H beam and steel I beam rods
Those motor work very well with both 440 size intakes and Max Wedge size intake size intake ports heads

If you want to "lighten" the crank for lite-weight pistons/rods, why would you want to add weight with Mallory Metal?

If you're going lighter, it normally allows one to take weight out instead of adding. On a 360, for example, using SIR or Scat I-beam rods with light pistons similar to SRP flattops, not only would you be able eliminate the extra balancer and converter/flexplate weight, you would need minimal, if any, Mallory metal to totally internally balance the assembly.

It's also my understanding that internally balancing an engine by removing the external balancer and converter/flexplate weight is better for crank & bearing durability and obviously makes it easier to find more common neutral components for the crank ends.

Going heavy to light is generally easy, remove counterweight mass. Discovering you need beefier parts is generally expensive, as you add counterweight mass. Or going from aluminum rods back to steel. S/F....Ken M

It's going to take more time. Have to make up weights, spin th ecrank to determain the weight adjustment needed. It it's substantial it could have the counter weight trimmed. Need a large lathe and a good estimate of the amount of thickness to be removed. Then back on the balancer for final balance. Mor etime and money for sure. Is it worth it? Not on a sub 7000 rpm bracket motor. Previously with a thinner pin and lighter piston the bobweight was 2222 grams. At that time it had the counterweights trimmed. New pistons, rods, and crank (same exact style Molnar 4.500"stroke, 2.200" pin and 7.100" rods). Current 2367 gram bobweight with the standard counterweights drilled for balance. It's quicker now than it was previously.
Doug

The way I understood it, the CWT software now tells you how much to remove from the counterweights. It doesn't totally balance that way but then you drill very little. I like that.

This is for a 273 project that I am trying to put together. I choose 7K just as a starting point and probably anticipate 7.8 to 8.4K. From the info I read, adding more weight(balancing w/ mallory) causes more deflection of the crank as rpm goes up and can cause the block to split.. Wasn't sure lightening the crank was a good choice.

Mallory metal is only required when the counterweight isn't heavy enough.

A common example would be wanting to neutral balance an externally balanced crank.

Get the bobweight down

What piston and rod are you going to use? How does their weight compare to factory?

I'd half fill the block, I did that with my 360.

I’m not sure we’re talking the same language here. I’m assuming you talking rpm when you 7K+? At any rate, here’s my knowledge on small block balancing. Remember the factory was looking for cost savings and not supplying lots of different parts if they could compromise. So, I assume you have an original 273 crank, rods and pistons to start with. The 273 crank should be forged steel. It is the same crank that was used in the 318 of the same year. The crank should not have a big hole drilled in the rod journals. It should be solid. The factory had one crank for these two motors, even though the 318 had heavier piston with a bigger bore. The way they fixed the balance cheaply is to put thick wall heavy piston pins in the 273 so the total weight of the 273 and 318 were the same. Cheap fix. So in your case, you will replace the rods and pistons with ones lighter than factory so when they balance your assembly, they will be able to remove weight from the counterweight of the crankshaft, not add.

An example where you would ADD weight to the counterweight ( heavy metal) would be would be in taking a factory 440 crank from a 68 with the stock rods and pistons and installing them in a 68 426 hemi with heavy 12.5 CR TRW pistons and heavy hemi rods. Take a factory hemi crank and install it in a 440 with factory rods and pistons and you remove weight from the counterweight by drilling holes.