Guest Justin Posted November 9, 2001 Share Posted November 9, 2001 Here's the problem, the headers glow at idle (particularly the #2 and #3 primaries if that means anything), also the car diesels at shutdown. So it's obviously running way lean. The previous owner said he jetted the carb down two sizes, am I correct in assuming that I need to Jet the carb back up? Also, how big a role does ignition timing play in these symptoms? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 9, 2001 Share Posted November 9, 2001 If timing is too high, the car will run on after shut off. Or if it is running too hot. What are the h2o temps. Also check for leaks on # 2 and #3 header or on the intake manifold. If air is leaking in either place it will get the exaust gas real hot. I dont think it is in the jets unless the are very lean. For only two tubes to glow it sound like poor fuel distribution, or air leaks. What type of intake manifold to you have? Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 9, 2001 Share Posted November 9, 2001 Whats weird about this though, on a V8 2 and 3 are on separate sides? A intake leak on both sides on the front of the engine? Manifold warped or the manifold didn't get torqued down right or retorqued. Of the top of my head thats all I can think of. Cup your hands over the carb, does it pick up rpm and smooth out? If so bad gaskets, or warped manifold or head surfaces? Regards, Lone Quote Link to comment Share on other sites More sharing options...
Guest Justin Posted November 9, 2001 Share Posted November 9, 2001 Well, just to clarify, all the primaries glow, just the #2 and #3 glowed slightly brighter than the others. That's after just letting the car idle for a minute or two. As far as coolant temp goes they're "normal" but right now the car has the original temp gauge and I'm not too confident in it's accuracy. As for the manifold, I don't the exact type, but it's a dual plane if that helps any...the motor is an LT4 crate motor w/ a speed demon 650 vac secondary BTW. After doing a little more reading on my own, I'll have to agree that it's probably not the jets... could a clogged idle feed restrictor be the culprit? I'll definately play with the timing to see if that doesn't help some... what're some good baseline settings to start at? Thanks for the advice... it kinda sucks being at the bottom of the learning curve. Quote Link to comment Share on other sites More sharing options...
Mike C Posted November 9, 2001 Share Posted November 9, 2001 A correctly functioning carburetor should not be drawing fuel from the primary jets at idle. Only the idle circuit. I would check the ignition timing first, scan for vacuum leaks, then adjust the idle mixture screws. Only then can you move along to sorting out the jets for the power circuit. You are running extremely lean, so proceed with caution above idle. Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 9, 2001 Share Posted November 9, 2001 Sounds like it's either really lean at idle (but then I doubt it would run very well), or very retarded ignition. Are you sure the TDC marks are correct? Around 69 Chevy changed the pointer and damper timg mark locations a bit. Mixing parts here can cause problems with incorrect TDC marks. Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 9, 2001 Share Posted November 9, 2001 Could be cam lobes r wiped would explain lean and opposite cyl .Hope I'm wrong.Justin still have original intake ? Want too sell it? Quote Link to comment Share on other sites More sharing options...
pparaska Posted November 9, 2001 Share Posted November 9, 2001 Check out this tuning page: http://www.bob2000.com/carb.htm It can help get you started. Quote Link to comment Share on other sites More sharing options...
labrat Posted November 10, 2001 Share Posted November 10, 2001 That holley tuning guide was great! I have a holley and an edelbrock, and there is no comparison as to which is easier to tune! Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted November 10, 2001 Share Posted November 10, 2001 Good sight Pete: very informative. I liked his "BOB" invention. I actually put together a jig of my own to recover oil from the "Bottom of the Bottle" of quart oil bottles: it worked fine...not as pretty as his: but mine worked just as well. Hey, does that mean I'm Rocket Scientist Material? Kevin, (Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 10, 2001 Share Posted November 10, 2001 I think you have the material for a Rocket Scientist Kevin. Or at least a Mad Scientist.. J/K. Regards, Lone Quote Link to comment Share on other sites More sharing options...
Kevin Shasteen Posted November 11, 2001 Share Posted November 11, 2001 Lone, I like the Mad Scientist idea; at least as a Mad Scientist I have a chance of taking over the world..., BoooHahahaHABoooHahahahahah (internet version of the mad scientist laugh)! Kevin, Yea,Still an Inliner) Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted November 11, 2001 Share Posted November 11, 2001 I think I'd just take over San Diego, or Maybe Florida, kick all Non-Z'ers out. Wouldn't want the rest of the world, so much of it is an arm pit anyway... Regards, Lone Quote Link to comment Share on other sites More sharing options...
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