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#84768 10/25/2007 9:25 PM | Joined: Sep 2007 Posts: 24 Apprentice | | Apprentice Joined: Sep 2007 Posts: 24 | I've got a 235 with fenton intake with 2 one barrel rochesters. What should the vacuum reading be with engine at idle? thanks | | |
#84769 10/26/2007 12:59 AM | Joined: Apr 2005 Posts: 275 Shop Shark | | Shop Shark Joined: Apr 2005 Posts: 275 | Take a look at http://www.centuryperformance.com/vacuum.asp It explains pretty well the various conditions. If you have a hi-perf. cam be aware your vac. will be lower than stock at idle due to valve overlap. Doug | | |
#84770 10/27/2007 2:50 AM | Joined: Feb 2000 Posts: 5,197 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,197 | My 250 with three one barrels has 19.5" @ idle. The amount of carbs should not change the vacuum. One or three, it will be the same. I would bet a stock 235 will be in the 18 to 20 range depending on the valves and ring condition. A bigger cam will lower it like Desertdog mentioned, could be as much as 2 to 3 inches lower. Timing can also raise or lower it a bit. Joe | | |
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