C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette
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Old Jul 1, 2011 | 03:58 PM
  #21  
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Scott, I understand now some and I will look at those papers. Thank you and it looks like I have a weekend project. I do have a HEI dist (all new now).

Damn chimp crapped on my keyboard downloading those papers, will clean the keyboard and get back to work.

Thank you and I will let you know how it goes later this weekend.

Dan
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Old Jul 1, 2011 | 04:05 PM
  #22  
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Originally Posted by dgood
Scott, I understand now some and I will look at those papers. Thank you and it looks like I have a weekend project. I do have a HEI dist (all new now).

Damn chimp crapped on my keyboard downloading those papers, will clean the keyboard and get back to work.

Thank you and I will let you know how it goes later this weekend.

Dan
Yeah, those chimps can be messy, but they are entertaining! I have an idea for a sitcom, it's just a midget with a helper chimp that he takes everywhere he goes. That's it. I think the scripts would just about write themselves............"Midget takes chimp to the grocery store, hilarity ensues........."

Let us know how ya do with the timing issues,


Scott
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Old Jul 1, 2011 | 07:11 PM
  #23  
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Could you chimp have taken a dump down your carb? I'm not sure even Sea Foam can deal with that.
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Old Jul 1, 2011 | 08:15 PM
  #24  
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Ok, just dropped the timing back down some more, right at about 6 at idle and 27 or so at 3000 rpm. Took it for a drive and I think it is doing a heck of a lot better. I think with the new dist and getting the timing right, I am finally almost there. There was a slight knock when going about 4500 rpms and stomping on it. I will see if I can go down a little bit more. I will need new springs for the dist though because it is almost stalling.

I highly recommend the seafoam. My car really drives a lot better and it seems quieter. No on to the vacuum leak in the headlights....

I think it just needed some money spent on it and it is all happy now.

Chimp is out throwing crap in the back yard now....weird!
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Old Jul 1, 2011 | 08:39 PM
  #25  
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Alright, 6 at idle, 27 all in, that's 21 degrees of mechanical advance, and that sounds just about right. Make sure it's really all in at 2,500-3,000 rpm. You should then be able to advance the idle timing up to 15 degrees, which will make mechanical timing all in at 36 degrees. If you are knocking at your present timing setup, there is a problem somewhere. Maybe a lean condition from the vacuum leak? Fix the vacuum leak and see how it goes. If you hear hissing from under the dash, you should be looking at your headlight system, here is a link that will give you a big headstart on how your headlight vacuum system works. In fact, that is the name of the article!


http://forums.corvetteforum.com/c3-t...tem-works.html


Scott
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Old Jul 1, 2011 | 09:28 PM
  #26  
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Any vacuum leak will cause the engine to idle rough so for testing purposes you can take a pair of forceps or a hemostat and pinch off the main vacuum supply line coming off the intake manifold. It wont effect the vacuum advance since that vacuum supply comes from the carburetor.

If you need to get the headlights up to drive at night simply remove the forceps with the engine running and you will have vacuum. After the lights are up apply the forceps again to stop the leak and smooth out the idle again.

Forceps/Hemostat
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Old Jul 1, 2011 | 09:46 PM
  #27  
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Headlight issue this weekend. Thanks for all the help getting this fixed. I will enjoy it for a day or two and dig into the dash.
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Old Jul 1, 2011 | 10:08 PM
  #28  
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27 posts to explain that you turn the distributer clockwise until it quits detonating.

not friggin rocket science.
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Old Jul 1, 2011 | 10:26 PM
  #29  
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Originally Posted by tortisevette
27 posts to explain that you turn the distributer clockwise until it quits detonating.

not friggin rocket science.
It seems you're not fully aware of the proper way to set ignition timing.
Setting the curve and total timing is quite a bit more involved than simply retarding it a few degrees if you want top performance.

But then again, I guess good enough is "good enough" for some people.
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Old Jul 2, 2011 | 06:16 AM
  #30  
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Bob, he did not read the whole thread or he would have realized that I had other issues on top of just timing. Thanks for all those that helped. Some people criticize peoples lack of knowledge on some things, others help, I prefer the latter especially when my car runs 10 times better than when I started.
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Old Jul 2, 2011 | 02:21 PM
  #31  
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My hissing problem behind the dash was broken lines on the heater control panel!
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Old Jul 2, 2011 | 02:56 PM
  #32  
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It is too nice out here to play in the garage. Maybe monday we will deal with the headlights.

Dan
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Old Jul 2, 2011 | 04:37 PM
  #33  
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Originally Posted by tortisevette
27 posts to explain that you turn the distributer clockwise until it quits detonating.

not friggin rocket science.
nice contribution.....i smell a troll
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