I'd like to know if somebody can explain what the numbers that are on Honda and Acura proportioning valves mean.

The prop valve on my 89 Civic Si (front disks and rear drums) has the number 25/30.

Two other valves that I picked up in a junk yard (off of cars with rear disks) have the numbers 30/30 and 35/40.

Now obviously it's not a percentage, or the numbers would have to add to 100.

I'm assuming that it's a ratio.

But then if that is the case, a 30/30 valve would be the same as a 40/40.

So, what gives??

Wes V