SO simple mods like cold air intake and exhuast change the timing of your car? If so where should it be at. Thanx in advance

 

Your sentance structure isn't complete. Are asking if those simple mods changed your timing or if you SHOULD change your timing with those mods added?

The ignition timing should not have been changed by adding those bolt-ons. For simple mods or no mods at all advancing the timing will bring more power but get you closer to pinging. (more power being 1-3 hp) Advance it till it pings and then retard it a little. If you want the max power run premium gas all the time with your timing advanced as stated. Simple mods and just advancing the ignition timing will not bring loads of power anyway so it probably won't matter a whole lot of you change the timing for your usual spirited street driving. I usually don't even use a timing light. If my oil pump is set right, then the distributor mark at the center of the adjustment plate is dead on 12 btdc. I believe that is where the book says to set it at the factory. I advance it a little beyond that and leave it there. That's maybe 15-17 ? BeforeTDC.

 

sorry for the inclearity, but recently my car started to backfire every so often, and the sound of my exhuast is not steady, every couple seconds it burps. Any ideas?

 

sounds like a misfire. Probably not ignition timing. You could have a bad spark plug or bad plug wires.

Worst case you could have low compression in a cylinder or two or be leaking oil into the cylinders. (engine rebuild time)