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Found out why it was smoking... Now what?

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Old Sep 25, 2011 | 02:08 PM
  #1  
FDLS6's Avatar
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Unhappy Found out why it was smoking... Now what?

My newly built motor smoked quite heavily after I got it running. It was extremely frustrating as I was very careful with the build. Compression was excellent and the heads were fresh, so I was concerned that I might have a problem with the oil rings. After pulling the intake and valve covers, I've finally found the problem.

When shining a flashlight into the intake runners and looking down at the intake valve spring, you can see just a little light at the base of about 5 of the intake springs. It would appear that the intake runners were ported a little too far and broke through into the the corner of the spring seat. These were very expensive Absolute Speed ported LS6 heads. I bought them years ago and finally got back into the project. That company seems to have vanished and I'm trying to decide what to do. I don't know if I could have a head shop weld back a little material back to the roof of the intake runner then smooth it out. I think there is a decent amount of material under the rest of the spring so I don't think this would necessarily crack or break, I think it's just a matter of getting it sealed back up.

The heads were to have flowed around 320 intake, 235 exhaust. I had them milled down to about 57.5cc's. They have I belive they have comp 977 springs and 2.05/1.57 valves. The car really ran strong with them but I never dyno'd. I'd hate to start from scratch (with new heads), but I'm afraid I may have to.

Note to "professional" porters. It's a lot easer to take metal away than it is to add it.

Has anyone had any experience with this type of issue and the weld/repair? I'd go to town with some JB weld, but I don't think that's going to cut it!
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Old Sep 25, 2011 | 04:15 PM
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Well one there is no pics and 2 I wouldnt take the advice on if they can fixed or not over the internet most 99.9% of the people who would post. Your best bet is to take them off and either go to a local shop that does head work or find a sponsor who is willing to take a look at them for you.
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Old Sep 25, 2011 | 06:18 PM
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Almost any good head porter could be able to heliarc the spots and smooth out the weld. I would have them touch up the spring seats so they are flat after welding.
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Old Sep 25, 2011 | 06:53 PM
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heads gotta be pulled off anyway, take em to a shop and see what they say.
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