You said you have the regulator set to the lowest rate...........meaning you have it screwed all the out.....counter clockwise?

yes.thats where i get the most water

The most water coming out of the dump or relief port?

only exit i have are the exhaust and one dump with the relief value

You said gauge is pegged.........what's the range of the gauge? 0-15, 0-30, 0-50?

0 to 35

There has to be a blockage somewhere. You still have the dumps off the rear of the intake?

no.The only restriction i can think of is the s pipe is to close to the end of the riser causeing a back up kinda.everything is clear.i think i saw some deals you block off some of the holes on a bravo to decrease the water intake to help this sence my lower unit is so deep in the water

You shouldn't need to do that with the relief valve. At what speeds/RPMs are you seeing the excessive pressure?

mid to wot