how much to advance timing

[brandons 95]

what is a safe amount to advance your timing when you put adjustable cam gears on, what should normal vacum reading be at idle my gauge says about 18lbs is that good

 

[clipse0001]

mine HKS gauge does not even go up to 18 lbs of vac pressure. When idling im between half to .6 bar which is like 7-8 lbs.

 

[brandons 95]

i have the autometer gauge and is goes to like 30 but it may not be in lbs im not sure my car has been in the shop sitting on a dyno for the past month or i would go check it out

 

[brute]

Well I would assume that your guage is in pounds... or so I would hope you wouldn't be running 30 bar (~441 lbs)... haha, anyways... that's all I had to say about it

 

[clipse0001]

I believe that all US gauges are in inHg which is inches mercury for vaccum and lbs pounds of boost. The ### gauges are in bars.

 

[andymoraitis]

what is a safe amount to advance your timing when you put adjustable cam gears on, what should normal vacum reading be at idle my gauge says about 18lbs is that good

Timing advance and cam timing are two entirely different things. Timing advance controls when the ignition fires while advancing/retarding cams deals with valvetrain events. Both are sensitive, however cams should always be degreed (adjusted) on a dyno to see where the most power is made. Failure to do so could result in major valvetrain damage from overadjustment.

Also, the above poster is correct. Vacuum is read in in/hg (inches of mercury). Depending on your altitude, 18-22 in/hg is about right on stock cams. More aggressive cams will lower this number as will increases in altitude (thinner air).

Hope that helps,

Andy

 

[oldman]

Timing advance and cam timing are two entirely different things. Timing advance controls when the ignition fires while advancing/retarding cams deals with valvetrain events. Both are sensitive, however cams should always be degreed (adjusted) on a dyno to see where the most power is made. Failure to do so could result in major valvetrain damage from overadjustment.

Also, the above poster is correct. Vacuum is read in in/hg (inches of mercury). Depending on your altitude, 18-22 in/hg is about right on stock cams. More aggressive cams will lower this number as will increases in altitude (thinner air).

Hope that helps,

Andy

Well said.

 

[jepherz]

Just a random tidbit of info, 2 inHg for every 1psi