Ok so I have a 650cfm edelbrock carb along with one of those diamond low profile air cleaners. There are times when it's cold outside and I start my car it has a backfire, sometimes causing a fire sometimes not. I think my timing is off a bit. Now I have some questions, what would cause these backfires? Then do the low profile diamond air cleaners happen to catch on fire a lot because of the foam filter? Lets say my timing was adjusted to almost perfect and it still had these backfires, what would I do to stop the backfire.

Then finally I bought an 14-inch dia. 3 inch profile air cleaner to replace the diamond cleaner but it sticks up to high? Is there a hood I could get other then some huge scoop.

Thanks.

 

If you suspect the timing is off, check it and adjust as needed.

Timing could cause the fires you describe.

Other causes: Bad valve settings, cam phasing, hot spots in the chamber, etc.

 

What is cam phasing and what do you mean by hotspots in the chamber? Sorry I don't know too much about cars and am only in my second qtr. of my Auto class.

 

Cam phasing is a term for the relationship between the valve timing, piston
position and in this case, spark timing as well.

Don't be too concerned with this unless you just completed a cam install.
If the cam is too far retarded, and the timing is not set properly backfiring
can occur.

Hotspots can cause pre-ignition of the fuel mixture while the intake valve is
still open. A hotspot can be caused by an incorrect spark plug heat range,
a burr of metal, or flashing in the chamber, or on the piston crown.

This is also something that you need not worry about unless the engine
was just assembled and the burrs/flashing was not ground down.

Try your luck with the timing first and let us know what you find.

 

I agree on the timing issue. Get a timing light and check it.

 

I agree with checking timeing first, that would be the most common cause of the backfires. Now for the cleaner you can get a drop plate from a performance shop that will lower your filter about an inch.

 

2 of my spark plug wires were on the wrong plugs once and it backfired through the carb too (I'm guessing that is what yours is doing) and I fixed them and it was fine. the car also had a major power loss. but this is basically what off timing would do too...

 

If it only does it when cold, you might check your choke settings. Sounds like it could be a lean condition to me.