470 runs out of steam at 5100 rpm

Been through this before! The shop's set pressure only on the springs it floated terribly!

"They must be installed to the correct height period" for the spring used!

I had a set done and the work was correct based on seat pressure, the height was all over the place and when adjusted per spec the 383 went to 7800+ no issue! I am a fan of the installed spring height only!