Redbear and myself worked out that an average Chakat would be closer to 250 to 300 kg. Goldfur has said they are a mix of genes and that they are a mix of feline genes as well as human.

Cool. So my calculations of 250 or so for the 1.7m tall chakat meets closer to what I was thinking then.

Guess I'll have to redo all my calculations and repost my old work.

And the fact that the first Chakat was tiger based, and the mother was a Tiger. So, your original calculations were like 45kg under what they really should be?

From what my first charts were, it certainly looks like it.
So the next question then is, what percentage increase is applied to the standard chakat weight to balance this new realisation out?

Would probably have to be around 20-25% (22% being closer)

Keep in mind that in order to have the strength described, the anthro half has to have at least a similar muscle weight ratio to that of a big cat also, meaning their muscles are very dense up top. As well, the anthro abdomen is mostly a band of muscle and connective tissue, so it is also much denser than that of a human.

As far as which big cat is closest in overall size... to estimate, I'd look for out the average height of a 5'6" woman from heel to waist, and match that against the shoulder/withers heights of big cats.

That's actually not right, since all vertebrate muscle tissue has a very narrow range of variability for the strength:weight ratio... approximately 25 to 30 Newtons per square centimeter of cross-section area. What gives the illusion of certain animals being so much stronger than humans is merely a result of their mechanical advantage as levers (how the muscles are attached, how big the muscles are, and bone length and size), as well as the creature's pain threshold.

For their size, humans are actually extremely strong. You hear the "fact" that chimps are stronger than men repeated everywhere, but this is scientifically false: chimps have a higher pain threshold than humans, and shorter limbs, so they can more easily use a higher percentage of their maximum muscle strength potential. Humans, with their more-developed brains, and their gentler lifestyles, are less able to normally push past their "failsafes" -- you can feel it as pain when you try to move something too heavy, and your brain orders the muscles to stop before you can hurt yourself trying. Physiologically, a human at their peak of fitness is notably stronger than the average chimp.

In life & death moments of extreme stress, the huge doses of adrenaline can numb the brain's pain sensitivity and bypass those failsafes, and unlock the true strength of humans. When that happens, it usually makes the headlines as feats of "superhuman strength" -- mothers lifting cars to save children, or a bear attack victim kicking the crap out of the bear, for example. Those failsafes are vital to preventing self-injury -- without them, human muscle can literally tear the body apart, breaking bones, dislocating joints, ripping tendons, and rupturing vital organs. In those rare cases when it happens, serious self-injury can and certainly does occur.

And now I'm picturing those weight lifters who have ripped, dislocated, and blown out parts of their bodies and I really wish I wasn't.

I heard on Discovery Channel that if you removed the safety that our brain puts in we could all lift a car. But we'd destroy the skeleton.

Bone is stronger than concrete... and yet the muscles can still snap the strongest long bones like matchsticks, if they flexed at maximum force. Anatomy is fun!