We would have to make examples of what Computation1 is and what Computation2 is to make a prediction if certain types of workloads will impact the ratio of their performance.
Example:
s=performance.now();
r=0;
for (i=0; i<1000000; i++) r+=1;
t1=performance.now()-s;
s=performance.now();
r=0;
for (i=0; i<1000000; i++) r+="bladibla".match(/bla/)[0].length;
t2=performance.now()-s;
console.log("Ratio: " + t2/t1);
For me, the ratio is consistently larger in Chrome than in Firefox. Which workload would reverse that?