Put a mechanical gauge on the system, see if the pressure still lags. If not, you may have an issue with your existing dash gauge and/or piping; and nothing wrong with the engine and accompanying parts and pieces.
Geoff
1955 2nd Series 3600 235 cid, 4 sp. - Current 1979 Chevy K10 350 cid 4 sp -Sold 1955 2nd Series Wide Window 283 cid 3 sp - Totaled
