motorman
Well-known member
the 30-30 cam was speced at .025 when it came out but there was not enought vacuum for the FI to run correctly so they changed it to .030Tom Bryant said:Factory recommended clearance for the 097 was .012 and .018. Most of us set the intake to .008 to get a little more intake duration. You will hear a lot of old timers say 8 and 18. Of course the 30-30 cam was .030 and .030. Hence it's name.
In this area of the midwest regular leaded gas back then was 90 or 91 octane at most stations. Low octane (89 and 88) started showing up in the 60s. Sunoco was one of the first with their custom blending pump which started with 190 (89 octane advertised as an economy fuel that we called p*** water) and originally had every graduation by 10s up to 260 (104). The idea was you could blend your gas at the pump to get just what your car needed.
Other stations just had regular and premium. Middle grade is a product of the unleaded period. Leaded premium usually was 97 or 98 except for Union76 which was 104. On the Sunoco pump scale 240 (98) was premium and was priced with other brands premium. 250 (100) and 260 (104) were high performance fuels.
If you had a Union 76 station close by it was the real bargain. Since their 104 premium was their only premium it was priced the same as competitor's premium so you saved a couple cents over Sunoco. The bottom line is that in the '60s you had no problem buying the right fuel at local stations for your 11:1 muscle car with all the timing cranked in it could take.