Nonsuch max possible score 423?

[whythis11plus]

I am guessing it as below.

SET 141
Nonsuch English 141
Nonsuch Maths 141

But the max score obtained is 406. So may be each of the above is for 136 instead of 141.
How do I know these nonsuch scores are standardised.

Thanks and Regards,
Wt11p

[tiffinboys]

Suppose maximum score for each element is 140. If no candidate gets highest in all 3 elements, the total will be lower than 420. Highest aggregate score of some one was 406.