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TR6 TR6 Proper vacuum readings?

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I had the Vacuum Gauge hooked up to my 74 just yesterday. I never had a full movement from one hash mark to the other, but somewhere inbetween. Not a real rapid quiver, more like an occassional rise and dip.. My engine has 103k miles and has had no work other than replaced bearings. I think with engine wear, the needle will be a little less than steady.
 
c74
Check out the web link in the earlier post. It has pictures for different conditions.
They seem to match conditions well.
 
thanks norton,
my engine is totally stock but my vacuum guage reads most like scenario '3'. the needle moves in much the same manner but is quite a bit more rapid.
any thoughts?
c74
 
c74, since you can rule out the "high performance" cam and the fact that your reading is about 17 in-Hg, I'd say that the quivering needle indicates normal wear, possibly a bit of valve seat recession or wear of the cam lobes.
I wouldn't be concerned. You might be able to get a little higher and steadier reading with a few degrees of timing advance.
 
thanks guys, this is reassuring.
right now it is not running and wont be until the spring so i'll put advancing the timing on my list of tweaks for the spring.
 
Norton47 said:
Car is running well. Plugs seem to be getting some color the rear 3 are getting more than the front 3 but none are white.
I did get the carbs to respond to lifting the whatca callit and not stumble all though they did at first but by turning clock wise to richen that stopped.
I left the timing at 20 degrees advanced without vacuum for now. What a relief.
Thanks for the help and support.
Click to expand...


i know that this is an old thread but i thought i would try making contact anyway. My car has the same readings. What was your final vacuum reading?
 
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