Thought somebody might find this useful if you are having vacuum issues and want to learn a little more about your engine. You can make one of these with some fuel hose slipped onto an over the counter vacuum gauge, super cheap.

 

 

...my Brat holds steady at 20, I dont know if that is typical or not though for these cars.

Edited August 18, 201114 yr by Freds404

this one looks my lysle vaccume gage

I Like that! ... Where I could buy one?

It is the least loved yet cheapest and one of the more informative diagbnostic tools there is, long before puter or engine analyzers.

if you have a carb, vacuum gauges are essential for tuning for sure.

for fuel injected cars a vacuum gauge like this is still useful, correct? 

for fuel injected cars a vacuum gauge like this is still useful, correct? 

Yes, since it also diagnoses mechanical stuff, like valves, rings, collapsed clogged exhaust.

Lol, if you're high altitude, you may need to adjust those reds and greens.  16 inches ain't too bad around here.  I don't think I ever seen one hit 22, outside of snap-closed-throttle.

Vaacum guages are great tools, Mine however is somewhat exotic it initially saw service in the cockpit of a WW2 P400 Aircobra in the South Pacific brilliant bit of gear for diagnosis work though and even a cheapy is worth the effort they will save you countless hours when diagnosing problems.

I have mine permanently under the hood.  The needle is a little shakey when cold but when warmed up it sits solidly on 21" at idle.  I also love my Wideband O2 sensor.

 

Both these tools are excellent for tuning and diagnosis.

Edited August 23, 201411 yr by Dirk