[USAFquez]

I just got my 383 SBC up and running again. I'm using Holley's EFI system with computer controlled timing. I think I may have my timing off a bit. I'm getting a loud pinging/popping sound from the engine whenever I try to give it gas when the RPM's are real low or when I gas it in a higher gear. I don't see anything out of the norm with my timing. I feel like I've had this problem before but I can't remember how I fixed it. Any advice?

SPARK

AFR

 

[USAFquez]

I'm breaking in the motor without the blower and I'm running 91 octane instead of E85. It did sorta sound like a backfire from the intake but I'm not 100% sure. I'll see if I can try and duplicate it again with a video and post it on here. Then I'll back the timing off a bit.

 

[USAFquez]

if your breaking it in without the blower then wont you have to go and remap it when swap in the blower?? what kind of blower btw?? boost level ?? just trying to help:beer:

Nah, I'm using the same map that would be there with the blower. Holley EFI has a self-tuning feature where you set your AFR and depending on what the O2 reads, it'll adjust the fuel map to try and match the AFR that was set. When I put the blower back on, the part of the map where boost is applied wont be tuned, but the rest will be. I'll just have to ease into the boost slowly so it'll "learn".

The blower is a Procharger D-1SC

 

[USAFquez]

oh ok i see now. did you back off the base timing?
add some fuel to it and pull out about 3 degrees and see if it likes it hope it helps

OK, I'll try that out. I gotta put a couple of the spark plugs back in from checking them last night. They look fine. I'll let you know how it goes.

 

[USAFquez]

**UPDATE**
So I kept messing with the timing and fuel and I couldn't get the pinging to go away. Also the throttle was still really twitchy. So I called Holley' Tech line and they had me email them my tune and datalog. I got a call back within an hour saying my idle was all jacked up. Basically I had my ECU idle set to 900RPM but my throttle bladed were open too much and I was idling around 1100-1200. So my idle air controller (IAC) was constantly closed because it was trying to compensate for the extra air coming in. After a while, the ECU was trying to pull timing to bring the idle down. He had me close my throttle blades until the IAC read about 30% at idle on the Holley software. After that, the pinging went away and the throttle is super smooth coming off idle.