help new motor problem

[harleydadof2]

Just wondering if anyone could answer this problem.I have a new 350 350 horse when i started to break in the cam about 3 minutes into it the headers on pass side cylinders 4 6 8 started glowing red about 8 inches down the tubes.The timing is set the wires are new i thought i might have a vacuum leak so i sprayed some carb cleaner around the manifold to see if the idle would change and it did not.Then i thought i might be running lean but i dont think that is the problem because i tried 2 differnt carbs. this is just a brief run down so if anyone has any ideas or suggestions please let me know thanks Jeff.

[harry schulz]

as a retired mechanic i've found that LATE/RETARDED timing causes headers to glow....DO NOT TRUST YOUR CURRENT TIMING MARKS!try timing by EAR,run the motor at idle with vac.hose connected to the vac.advance if non electronic.slowly advance the timing and listen to the eng. speed up when you have advanced too far the eng.will get rough then back up slightly tell eng. idles smoothly.if the car PINGS on the hiway just keep backing up on the dist.tell you lose the ping.

[soup]

i put 350 crate engine in my exhaust pip,dont know if this will help youes and catylatic converter glowed, found out fuel pump put out 7psi , running 750cfm q-jet , manual on q- jet says 2-5 psi max or it will flood, my converter was allowing raw fuel to build causing glow

[soup]

don,t know what happned to my post, didnt come right ,i put 350 crate engine in and exhaust and converter glowed , new fuel pump put out 7psi, jeg,s manual states 750 cfm q-jet operates 2-5 psi anymore it will flood, converter was holding raw fuel,glowed changed to 5psi pump no problems, don,t know if this helps you

[COCACOLA_JUNKY]

like Harry said i wouldnt use the the timing marks. if it isnt cammed up too much u could check it by vacuum too u should have approx 17 psi on a vacuum gauge off the intake.i ran into the same prolly with my 83 chev kmalibu when i rebuilt my engine.changed the harmonic balancer and found my timing marks out approx 31-33 degrees wouldnt even start..
Del Gerlinsky
Former Gm tech