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3.4 DOHC Camshafts


  • 3.4 DOHC Camshafts

    Cam options for the 3.4 DOHC are few and far between. This is the most common reference given for regrinds.

    Steve Long Racing Cams INC.

    Cam Timing

    Because the cam gears are not keyed, the options for cam timing are nearly infinite. While this can cause a problem for the novice trying to set the cam timing, it also allows great flexibility for those with more experience. First, I must add that any painted timing marks are to be ignored. To learn more about how to set the cam timing, go here.

    It has been over a year now that the 13 degree exhaust retard spread across the internet as an easy way to get power out of this motor. It seems that another person has experimented with the timing on a ported engine mated to the automatic trans. It retains the 13 degree aspect but advances the intake cam as well to lower the powerband from what we had already tried. I hope this is right, 7 degrees advanced on the intake, 6 degrees retarded o*n the exhaust. As of now I do not know where this lines up the timing mark for 91-93, so you are o*n your own for figuring it out. I do however have a better picture to show the timing mark for the 10 and 13 degree timing. Basically, 10 degrees is what I thought 13 was originally. I am now running 13 on my car but the idle is a hair rougher than with 10.

    Stock Timing

    10 Degree Retard

    13 Degree Retard

    Update: 6-8-05 I have now tried 6 advance intake / 6 retard exhaust on a 94 cutlass and my 91 grand prix. The cutlass is an automatic, and was timed to stock from the belt stretch timing of -8/-8 rear bank, -4/-2 front bank. This obviously made the car idle and run better than before. The 6/6 timing was then applied. Wow...simply amazing for an automatic. The powerband starts lower, idle is smoother than stock timing, and low end is increased a nice amount. Top end was helped out as well over stock though with the auto, stock shift points don't go as high as you can with the manual. The owner also noted an increase in gas milage though I also tuned the chip with this timing done. I am testing the gas milage in my car now.
    6/6 timing on a manual car is a different animal, because instead of shifting at 6200, I usually went to 6600 or so (power dropped after 6600 with 13 degree retard on my motor). My car now only likes to make power to 6200 or so and then drops off noticably. The low end is a hell of a lot nicer and the exhaust note when I cruise around at 1500 is smoother. It no longer feels like its working hard below 2500 I am going to try some more settings out later after I tune my car how it sits and compare gas milage.

    The tools to do this are no longer made. You can make new marks on the dampener itself without too much issue. The stock timing notch is the exact width of 1 degree.
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