Is there a way to test seat pressure with the heads installed on the car?
Just realized this question. For me the answer is yes and no. I've used a tool similar to the one pictured below. As far as testing a unknown spring i don't believe these are accurate enough. What i did was bench test for the proper tension and right after installation i ran them with the tool to get a number. Didn't really matter what the tool showed, i would document whatever the readings were for later. Then whenever the valve covers were removed or i suspected something was up i would do a quick run thru to confirm whether any pressure was lost or inconsistant.
