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Miss after completing my head install

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Old Apr 12, 2012 | 12:26 AM
  #1  
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MonsterBilly
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Default Miss after completing my head install

I I finally have my heads bolted on and the car is running. However I have a pretty bad miss now. The miss was not there before I did the heads. Any Ideas?

I installed new plugs, other than that i have the same wires, cap rotor and everything else.

It also has a lot higher oil pressure than it had before. I did install new lifeters as well.
Old Apr 12, 2012 | 09:14 AM
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Did you check for vacuum leaks? Also, did you adjust the valve lash correctly on the new heads? When mine weren't adjusted just right I had a slight miss because some of the valves weren't opening/closing at the right time.
Old Apr 12, 2012 | 09:51 AM
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I'm kind if thinking its the valves. These heads have the stud mount rockers. I did follow the correct method but I'm thinking thats it.
Old Apr 12, 2012 | 10:42 AM
  #4  
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You can try to adjust them when the car is running. If you do this warm the car up a bit and start at the front. Loosen the rocker nut until you hear it start chattering. Once it does this tighten the nut back up until it stops. Once it stops turn the nut about a half turn more. This can be a messy process as oil will leak down the side of the engine. I used an old set of rocker covers and cut the tops out to help eliminate the oil spill.
Old Apr 12, 2012 | 05:50 PM
  #5  
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As I stated above (incorrectly), I dont not have your more common stud mount rockers. I have the pedestal mount rockers. they are adjusted with shims.

So i have it narrowed down to #6 cylinder. I remove the pug wire and there is no change in the rpm or the smoothness/roughness of the engine. I tried to change the plug wire with no change as well. I then took an extra valve cover i had and cut the top off it and installed it.
I also removed the plug and started it and the plug is sparking.

I did a compression test and it is fine as well. What the hell is the issue here????????????????????????????????????????????

I tried removing the shims under the
Old Apr 12, 2012 | 10:56 PM
  #6  
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Is the cam new? Does it have a different firing order than the previous cam?

I would start with the basics and go from there.
Old Apr 13, 2012 | 06:52 AM
  #7  
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If its a newer cam is may have a 302HO/351 firing order 1-3-7-2-6-5-4-8 instead of 1-5-4-2-6-3-7-8.

Though if you say you've narrowed it to #6 do a leak down test.
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