I just got a vacuum gauge to dial in my carb. I got it running smooth and steady at around 23, is that to high? Its a 68 289 with a performer intake and holley 4 barrel carb, other than that stock. I'm idling around 600-700 rpm warmed up.

Thanks.

 

Sounds about right, but don't tune a carb to the vacuum. You'll end up with timing that's too high and/or idle mixtures too lean.

 

vac depends a lot on cam specs too.

I typically see around 12 to 13 at idle

 

Yeah, stock cams tend to be really high vac for power brakes, emissions reasons etc.

I'm around 12 at idle as well.

 

omg yea...I was thinking that was a bit high as well. I didn't know that stock cams were that high. I idle around 900 rpm (idles like crap but sings at 3,4 and 5k rpms) with 10 inches of vacuum. So low that I had to buy a vacuum assist for my power brake booster, it requires 16 inches of vacuum to work.

 

Aren't those for sissys?

 

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your vacuum is 23? that really sucks...sucks get it?. Ahhh, ha, ha.

 

I had to buy one for my girlfriend.

 

Is there any problems with it being that high, or what can I do to lower it. I have the stick cam.

 

No there is no issue.

High vac can be desirable for several reasons...sissy power brakes (jk) like it plus carbs are a big fan of vac.

If there is no serious issues like a vac leak, valve or ring problems the idle vac you get is the idle vac you'll get. Its highly dependent on the cam particularly the number known as LSA (lobe separation angle) aka valve overlap.... as well as lift and duration to some degree.

The only way to lower your vac would be to create an undesirable problem.