Some background...I have now at my -85 Camaro iron Delco-Moraine rear disc calipers and original iron combination valve.I'm going to replace rear calipers and discs to -95bpr units.If bpr brakes don't make enough brake force to rear I have to increase rear brake line pressure.

Are spring and piston at that iron combination valve under hex nut which is underside of valve?
Also does someone have idea how much do I need to increase spring pressure?

 

Several choices of valves: the first-design 1LE valve, which is a bolt-in, an adjustable, such as Wilwood, or the spring modification that you are curious about. More about the latter below:

https://www.thirdgen.org/forums/brak...e-upgrade.html

JamesC

 

I changed mine in my iron PV to a 37"/lb. spring from Grainger. They come in a pack of five for about $5 Part # is 1NCF2 I believe.

 

So iron valve has same dimension spring as aluminium valve?

 

Apparently, it's working like a champ in mine.

I have a 1NCF2 spring for sale $2 shipped

paypal is: arvizu9618@***.net

BTW, yes, spring and valve are on the underside of the valve, I believe the hex nux is 3/4"

 

PM sent.