Vacuum Gauge and Boost Gauge differences?

BHP Addict

Back in a SEAT!!
Jan 31, 2006
Before you all suggest :search:

I am on my phone and it shows 1 of 112 pages with the search link somewhere around page 48 with no way of jumping pages lol

I need to know the difference between a Boost Gauge (PSI) and a Vacuum gauge (cmHg)?

What does the Vac gauge connect to and would it be worth having both?



4 8 15 16 23 42
Dec 23, 2004
As a rough guess a boost gauge shows the both boost and vacuum and is for turbo cars. A vacuum gauge will just show vacuum and will just be for normally aspirated cars.


Beer or Car?
Dec 14, 2002
South West
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Is there a standard vac reading the Ibiza should read on idle and when coasting in gear down hills etc (no throttle)? I've read the boost pressure's for mapped, standard etc but had a quick search and there are different readings people quote for vacuum. I'm a little concerned mine's iffy as vac at idle is 50cmHg and sits at 60cmHg when coasting.
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Listers, parts supplier