water pressure cross over pipe
 

I have a hp 500 with bm blower no water temp I put a by pass on my cross over and a 160 stat with holes Now I have no water temp and hi water pressure

First off, I'd change the stat to 140*. What size holes are in the stat? What size bypass hose? How much pressure are you seeing at WOT? And, You must be a friend of Charles?

Crossover pipe
 

Everyone tells me to use a 160 in fresh water and 140 in salt water. My by pass hose is a 1/2 inch isd. 3- 1/8 inch holes in high flow stat. Yes, I am a friend of Charles (How did you know ??!!)

I can see that if the stat will not open, due to cold lake water temps and the 160*, that the three 1/8" and 1/2" holes are not large enough combined to flow all the water that your pump is pumping, that this will cause you to have the high water pressure. I assume you are talking WOT pressure? Then again, with lack of flow thru the motor, it should build some heat to open stat, which would then in turn lower your pressure back to normal. With a stat, you shouldn't run the motor at speed until you get enough temps to open the stat just for the reason of too much restriction for the water to exit= high pressure as you are experiencing.
Never heard of the 140-160 statement, so can't comment on it other than my B&M manual says 140* is target temp. My high volume 140* stat has 3/16" holes. 2 weeks ago my temps were right around 145-150 and pressure was fine. Just for comparison.

You can lower your pressure some by enlarging the stat holes.

I've crossed paths with Charles a couple times on Cumberland and stay in touch by e-mail. He has mentioned a buddy that bought a 27' Fever last year that has a blower also, I assume it is you??????? Plus the Hamilton thing was a tip.