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Normal? vacuum numbers? (What does yours push?)

  • Thread starter Thread starter FastGT94
  • Start date Start date Aug 10, 2004

FastGT94

Member
Nov 20, 2003
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NW Burbs, IL
Aug 10, 2004
#1
  • Aug 10, 2004
  • #1
Greetings!

I just got done replacing practically every gasket on the engine with the exception of the head gaskets since my car was running lean on the dyno and couldn't be corrected with more fuel / less timing.

Before I go and spend even more $$ on a dyno tune only to have it tell me that I'm running lean again, what kind of vacuum numbers do your cars give out?

Mine has between 11-12 (Needle moves a bit) at idle (~700 RPM's) My cam is similar in size to a X-303 with a little less lift on the exhaust side but more duration on the exhaust (split reverse duration). Ed tells me that the cam should push around 13-15 and that I need to start checking hoses. (all the hoses are connected and fine with no cracks...)

My only two areas that I even think could have a problem is the upper to lower gasket since the egr tube was like a 32nd of an inch too long but I had figured that tightening the bolts on the upper would crush it down (made it out of soft copper tubing). Also, I noticed that, with a bit of force, I can turn the neck on the valve cover, since this is a place that also has vacuum, wouldn't this be a potential leak of at least a pound? Do either of these sound like they need attention?

If anyone with an aftermarket cam could take the time to quickly hook up a vacuum gauge and give me some readings, I'd really appreciate it.

If my numbers are indeed low, where else can I look besides the upper to lower gasket and the Valve Cover neck? Can a blown Head Gasket make a vacuum leak?

Thanks for the help! I'm hoping to finally have the car running and trouble free REAL soon!!
 
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