QWKDTSN Posted September 2, 2002 Share Posted September 2, 2002 Hey guys... Yeah my car finally runs enough to drive. I drove it into the parking lot next to my house last night, made a loop, then pulled back into my garage. What you don't know, however, is how long it took and how many times I had to re-start the engine I really don't know anything about tuning a Holley. I am just now learning what all the different screws do. The only real problem seems to be that the car loves to backfire. When under load or revving up the engine a bit, once in a while it'll spit a healthy pop through the carburetor and immediately die, and once in a while I'll get a nice 3 foot flame out of the venturis Might this just be an ignition thing? For a while the car would barely run when it was on the idle circuit and I'd have to always be into the accellerator pumps to keep it running. Then I realized that you turn the idle mixture screws OUT to richen the mixture. Ohhh... That helped a bit (1 3/4 turns out from the seat), and I learned how to adjust the idle speed. I don't have it down idling past 1000 rpm but think I'll be able to with my dad's help. I'm just curious how to stop this backfiring because it'll seem like the engine's running fine until I start messing with stuff, then suddenly it spits loudly and comes to a dead stop Quote Link to comment Share on other sites More sharing options...
QWKDTSN Posted September 2, 2002 Author Share Posted September 2, 2002 K... that was one of my concerns as there's no way fire should be getting up into the intake. What should I set my timing at? I'm running an HEI unit, stock besides a 55,000 volt coil (pretty sure everything else is stock) with the vacuum advance hooked up. Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted September 2, 2002 Share Posted September 2, 2002 Start with initial timing at about 10 degrees BTDC. When setting it, uplug the vacuum advance and plug the line. Re-connect the line after setting initial timing. Quote Link to comment Share on other sites More sharing options...
Guest greimann Posted September 3, 2002 Share Posted September 3, 2002 It sounds like your ignition timing is way off. Get that set up first, and tuning the idle should be a lot easier. Quote Link to comment Share on other sites More sharing options...
Guest pvtkary Posted September 6, 2002 Share Posted September 6, 2002 I have found that most problems are caused by the basics. when you built the motor, how did you degree your cam? Are your valves lashed correctly? Are you shure that you dont have a bent valve. A compression test would be a quick way to lay alot of demons to rest. No matter how out of wack your carb may be it can only cause a lean, or rich condition. Is it smoking? I also strongly suggest using colour tune which allows you to see the colour of the actual combustion to aid in tuning your idle mixture. If your timing is extreemly bad the car will be allmost impossible to start. Good luck Quote Link to comment Share on other sites More sharing options...
Guest pvtkary Posted September 7, 2002 Share Posted September 7, 2002 oh yea during the carb tuning process you may have fouled your plugs. you may want to pull them, and check. dont use a wire bursh to clean them. I have made this mistake before. The metal rubs off on the insulater, and makes a nice path to ground. Quote Link to comment Share on other sites More sharing options...
A. G. Olphart Posted September 8, 2002 Share Posted September 8, 2002 Someone who shall remain nameless has had an engine run rough and backfire due to crossed plug wires... just a thought. Quote Link to comment Share on other sites More sharing options...
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