Lean Backfire through TB

[grknss]

Hey what's up, I'm new to this board and here is my question.

I have a 2.8l in my 1988 S10 Blazer and I had the motor redone and had a hotter cam put in it. but it always seems to backfire through the throttle body.

I have since added MSD coil and wires, Holley 400cfm throttle body, hypertech chip I know I am forgetting more, but I have the reciepts and records of what I've done (it has been a while since I have messed with it --on going project truck)

any insights would be great, thanks

[88jbody]

Most likely a timming issue first thing I'd put a timming light on and see what it's sitting at and double check for crossed wires ect...

[grknss]

oh yeah, thanks but the timing was in spec. we even tried advancing and retarding it with no real changes.

[geoffinbc]

Are you timing with the ESC bypass wire disconnected? Be sure you are or your timing will be severly retarded

[grknss]

Are you timing with the ESC bypass wire disconnected? Be sure you are or your timing will be severly retarded

yes timing was done correctly, a friend of mine helped out (he is a GM tech)

[geoffinbc]

What did you time it to?