it’s a vw 2.5l 5 cyl with 312k miles. im trying to decide if i need to swap in a low mileage motor while i am doing my 6 speed swap this winter. ive read that the cheap compression testers from amazon or harbor freight with the rubber lines are innacurate, but they are like half as much as the better quality ones with a stainless streel braided line. i will probably only use it once. do you think it’s worth it to spend the extra money or should i just get a cheap one?
Anything with a fitting that threads into the spark plug hole should be fine. Differences between cylinders matter more than knowing if the numbers are off by a few PSI.