Looking for some advice. I have a SBC 400, Holley 740cfm TBI, 65lb/hr @ 24psi, .202 heads, 9.25:1 comp, cam has 62 deg overlap, .280" lift, and 207 deg of duration. Does anyone have an idea of how far I can advance timing without causing issues? I do not have the ESC (electronic spark control) module, knock sensor, or any of the wiring for it in the harness (my fault for not installing it during the original install of the EFI). I use Tunercat RT, LM2 and Ostrich 2.0. Any advice for the main spark table would be appreciated.

 

Are you using a vacuum advance dist.? You should if you are not using the est & knock sensor. Get a spring/weight kit, set your timing to 6* w/out vacuum advance hooked up. I like to set the timing to get the highest vacuum reading & listen for spark knock under load. Then retard the ignition slightly if knock is heard. The spring/weight kit lets you fine tune the advance, come on fast or slower. Most sbc like between 34-38* total timing, this is when the engine is revved up & no vacuum advance hooked up.

 

No, I'm using the factory tbi distributor from an 1989 350cid pickup with a 7747 ecu. I have full control over the spark table in the tuning software. Thanks for the reply though. You had what I was looking for 34-38* full advance?