The Effect of Vacuum Advance on Cooling - PART 2 - Canisters

Discussion in 'Big Block Cadillacs' started by Darius, Mar 14, 2020.

  1. Darius

    Darius Well-Known Member

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    This second posting about vacuum advance contains details about specific vacuum canisters. It can be very useful in choosing a unit for your particular engine setup. When compared to the numbers stamped on you existing canister it provides the point at which they begin to work (amount of vacuum) as well as the total advance provided.

    The material printed here would NOT hold the format of the webpage and is therefore more difficult to use. I suggest you use the link below, scroll down to the section specific to you type of distributor (HEI or pre HEI), the look for numbers and specs that fit your needs.

    Best,

    bro. d


    http://outintheshop.com/faq/Vac Adv Spec.pdf

    Technical Information Bulletin Rev H 9-30-07
    Distributor Vacuum Advance Control units
    Specs and facts for GM Distributors


    HEI Listing

    NOTE: The HEI distributors use a longer control unit, so the non-HEI and HEI vacuum advance control units cannot be interchanged.

    The following listing (HEI) is as follows: The first four part number listings are the 4 numbers that are most commonly used in a Chevrolet performance application. The “AR12” can is the most versatile and user-friendly unit for a good performance street engine. The AR 15 and AR23 are almost identical, with only slight variations in their “start-stop” specs. The “AR31” can is the HEI equivalent to the “B28” Hi-Perf can used on the early engines:

    The advance comes in very quick on this unit – too quick for many performance engines. Do not use this very quick unit unless you have a cam/engine combination that really needs an advance like this. It can be used as a tuning aid for problem engines that do not respond well to other timing combinations, and can be successfully used in applications where direct manifold vacuum is applied to the can (see paragraph and discussion on this above) After this, the listing is by Echlin part number. All GM HEI vacuum advance units are interchangeable, so you can use a Cadillac or GMC Truck unit on your Vette, if that’s what you want to do.


    HEI Distributors:

    P/N ID# Application Starts @ “Hg Max Adv

    (Distr. Degrees @ “Hg.)

    VC1838 AR12 1975 350 Buick 7-9 7 @ 10-12

    VC1853 AR23 1976 350 All Calif. 5-7 7.5 @ 11-12.5

    1976 350 Vette Calif., Exc. Hi Perf

    1976 400 All, Exc. Calif

    1975 350 4-bbl

    1974 350 All w/1112528 Distr.

    1978 350/400 Heavy Duty Truck, Exc. Calif, Exc. Hi Alt.

    VC1843 AR15 1977 305 All Exc. Hi Alt, Exc, Calif. 3-5 7.5 @ 9-11

    1974 400 All w/2-bbl

    1977 305 El Camino

    1976 262 Monza Exc. Calif

    1976 350 Vette Hi Perf, Incl. Calif

    1975 350 Z-28

    1977 305 Buick Skylark

    VC1862 AR31 2-4 8 @ 6-8

    ----------------------------------------------------------------------------------------------------------------------------

    VC1703 N/A 1978-79 Vette Special Hi Perf 3-6 5 @ 7-9

    1979 305 El Camino Calif.

    1978-79 350 Blazer & Suburban

    1979 Buick 305/350

    VC1825 AR1 1976 454 Caprice, Impala 3-5 9 @ 6-8

    1975 454 Caprice, Chevelle, Monte, Suburban

    VC1826 AR2 5-7 12 @ 10-13

    VC1827 AR3 5-7 9 @ 9-11

    VC1828 AR4 1975-76 350 Buick & Olds 6-9 10 @ 12-14

    1976 350 Pontiac

    VC1831 AR7 6-8 12 @ 14-16

    VC1832 AR8 1975-76 455 Buick Electra 4-6 12 @ 12-14

    VC1833 AS1 1975-76 500 Cadillac Exc. Calif. 4-6 14 @ 15-16

    VC1834 AR9 4-6 13 @ 13-16

    VC1835 AS2 1975-76 350 Olds 5.5-7.5 12 @ 15-17

    VC1836 AR10 1977 305 All Hi Alt, Exc. Calif. 3-5 9 @ 11-13

    1977 350 All exc. Calif.

    1977 350 Vette Exc. Calif, Exc. Hi Perf

    1976 305 All Exc. Calif

    1976 350 All Exc. Vette, Exc. Calif

    1976 350 Vette Exc. Calif., Exc. Hi Perf

    1975 262, 350 All w/2-bbl carb

    1975 350 All 4-bbl w/ 1112880 & 1112888 Distr.

    1977 305 Chev Truck Light Duty

    1975-76 350 El Camino 2-bbl

    VC1837 AR11 1976 305 Blazer, Exc. Calif 6-8 12.5 @ 10.5-13.5

    1976 350/400/455 Pontiac 4-bbl

    VC1839 AR13 4-6 12 @ 11-13

    VC1840 AR14 1975-76 350/400/455 Pontiac Firebird 6-8 10 @ 9-12

    VC1841 AS3 1975-76 500 Cadillac Calif. 5-7 10 @ 13-14

    VC1842 AS4 1976 350 Olds Cutlass 5-7 12 @ 13-15

    VC1844 AR16 3-5 12 @ 13.5-15.5

    VC1845 AS5 1978-79 425 Cadillac w/F.I. 4-6 14 @ 14-16

    1977 425 Cadillac

    VC1846 AR17 1977 301 Buick Skylark 3-6 13 @ 10-13

    1977 301 Pontiac

    VC1847 AS6 1978 403 Motor Home 4-6 12 @ 12-14

    1977-79 350/403 Buick LeSabre Hi Alt, Riviera, Olds

    1977-79 350/403 Pontiac Hi Alt

    VC1848 AR18 4-6 12 @ 9-12

    VC1849 AR19 4-6 12 @ 7-10

    VC1850 AR20 1977 350/400 Pontiac 4-6 10 @ 8-11

    VC1851 AR21 1977-79 350 Buick LeSabre, Century 5-7 12 @ 11-13

    1978-79 350 Pontiac

    VC1852 AR22 77-78 305/350/400 Chev Truck, Heavy Duty 7-9 5 @ 12-14

    1975-76 350/400 Chev Truck Heavy Duty

    VC1854 AR24 3-5 13 @ 10-13

    VC1855 AS7 1977-79 260 Olds Cutlass 3-5 15 @ 10-12

    VC1856 AR25 3-6 15 @ 10-14

    VC1857 AR26 3-6 12 @ 13-16

    VC1858 AR27 1978-79 305 All 3-6 9 @ 11-13

    1978 350 Camaro

    1978 305 Chev Truck, M/T, Light Duty

    1978 350 Chev Truck Hi Alt

    1978 305/350 Buick & Olds

    1978-79 305 Pontiac

    VC1859 AR28 1979 350 Vette Exc Hi Perf 3-6 10 @ 9-12

    1978-79 305 w/1103282 Distr., Incl. El Camino A/T

    1979 350 Camaro, Impala, Nova, Malibu, Monte

    1979 350 Suburban

    1979 350 Buick Century

    1978 305/350 Buick & Olds

    1978-79 305 Pontiac Hi Alt.

    VC1860 AR29 3-6 12 @ 10-13

    VC1861 AR30 1978-79 301Buick 3-5 13 @ 11-13

    1979 301 Olds

    1978-79 301 Pontiac

    VC1863 AR32 2-4 10 @ 11-13

    VC1864 AR33 1978 305 Chev Truck, A/T, Light Duty 4.5-6.5 13 @ 11-13

    VC1865 AR34 1973-74 350 Vette Special Hi Perf 3-5 15 @ 8.5-11.5

    VC1866 AS8 1978-79 425 Cadillac w/carb 3-5 14 @ 13-15

    VC1867 AS9 2-4 10 @ 8-10

    VC1868 AR35 1979 305 Chev Truck & El Camino 2-4 10 @ 6-9

    1979 305 Buick & Olds

    1979 305 Pontiac A/T

    VC1869 AS10 2-4 12 @ 8-11
     

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