How much vacuum at idle?

[kreymis]

i have a 331 with s-trim. my vacuum gauge reads only 10 psi at idle. is that enough or is that right. i have an afm b31 cam.

 

[toyman]

i have a 331 with s-trim. my vacuum gauge reads only 10 psi at idle. is that enough or is that right. i have an afm b31 cam.

Not 10 psi more likely 10 in-Hg. Mine with a comp 270HR cam reads about 12 in-Hg. Probably normal with the cam.

 

[Black Stampede]

Also will vary based on where your idle is set.

 

[Grn92LX]

call anderson and see what they say that cam should make. Sounds way low to me.

 

[revhead347]

Sounds about right. I make about 7.8 with my Trick flow 3 cam. The joys of manual brakes.

Kurt