73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => 73-87 Chevy & GMC Trucks => Topic started by: achevy1978 on October 14, 2013, 09:46:33 pm

Title: vacume question
Post by: achevy1978 on October 14, 2013, 09:46:33 pm

hi
my vac advance off the dist goes to the left front of quadrajet. i pulled it off to check timing
after changing intake gaskets and there seems to be no vacume, engine does not increase in rpm when i take it off... i sprayed carb cleaner around manifold  and no rpm change.

Title: Re: vacume question
Post by: Boone83K10 on October 15, 2013, 07:44:23 am

vacuum advance is usually on a ported vacuum source, on at least 95% of street engines. Ported vacuum is closed off at idle. That is why RPM didn't change.

Title: Re: vacume question
Post by: Irish_Alley on October 16, 2013, 12:24:18 am

what boon said. also most people on here say to to move it to another port if you can. the ported advance is more for emissions