1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

Backfires Without the Nest????

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Old 01-11-06, 04:19 PM
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Backfires Without the Nest????

I took off the Rats Nest today in my shop.
I followed the "Mods Made Easy" book to the letter.

Now i seem to have a decel backfire or coasting backfire

The idle is also way down like a V-8 with a lumpy cam (sorry for the piston reference)

do i need to re-time it now?????

Any thoughts????

Oh factory exhaust with cats emptied...
1984 GSL Stick
Racing beat Air Cleaner
Fresh Tune
not much else

Jay
1984 FB
Old 01-11-06, 04:22 PM
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Tune it.....plugs, wires, check timing etc....

Double check there's no vacuum leaks
Old 01-11-06, 05:41 PM
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actually man...dont worry so much about it....yes you are gonna need to tune it a bit to keep it from backfiring....sounds like you are gettin too much fuel right now...so if you have a FPR...turn it down some....but this is very common after removing the rats nest...

-brenden
Old 01-11-06, 06:47 PM
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backfires are cool.. weld your exaust shut (no leaks) and shift near redline and impress your friends with the flamethrower...

why do people call this a problem?
Old 01-11-06, 07:14 PM
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Try it with a BP and no cats.......third to second is like an attack on the beaches at Normandy.
Old 01-11-06, 07:27 PM
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Originally Posted by SparkienSuggah

why do people call this a problem?
haha I want to back fire.
Old 01-11-06, 10:32 PM
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if i cut out a pice of tube to replace all three cats will it back fire some flames. sorry for butting in
Old 01-11-06, 10:59 PM
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Timing and exhaust leaks are what I would look into first. I have no rats, and have never had an issue with backfiring since I put the RB exhaust on and got rid of my leaky stock system.
Old 01-12-06, 01:08 AM
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okay okay...
those who like fire: retard your timing, foul your plugs, shift in the red and stand the **** back..

those who like cars that arent dangerous (crazies!): make sure your ignition system is in good shape(wires, plugs, cap+rotor, vac advance), with correct ignition timing (if not slightly advanced), ensure your carb is set correctly (float, bowl vent), or that your fuel injection system isnt behaving like my buddies nissan (dont ask - not pretty), make sure your air filter is clean, keep your cats too. consider direct fire ignition upgrade for better burn

im not sure about air injection and the anti-afterburn solenoid. i blockexd off my air injection doodads, but still have the anti-afterburn solenoid attached... only minor popping and muffler flashes until i push the car hard through 6k.. it seems to me that a sealed exaust system wouldnt shoot fire if the air injection+antiafterburn were working, because all the flaming would take place inside the headers and front pipe, but the exaust gas velocity might be high enough to carry this fire out through a straight pipe.

without any air injection/afterburn it may be possible to keep a rich, hot exaust mixture flowing out the pipe where it would ignite upon meeting the cool, oxygen rich atmosphere, resulting in MEGA FIRE... or it wouldnt ignite at all because its not hot enough at the muffler tip..

thoughts?
Old 01-12-06, 07:26 AM
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Cool

Originally Posted by aussiesmg
Try it with a BP and no cats.......third to second is like an attack on the beaches at Normandy.


I love it, its like a war in my tail pipe. Black your 7 out and wear a black tux you'll look mafia. Then when you backfire people wont realize it. they'll be on the ground cause they think your shooting at them
Old 01-12-06, 07:31 AM
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Oh and the tip of my muffler isnt cool, I cant touch it after about 5 minutes of hard driving. So I dont even want to think how hot the header is. (getting new exhaust muffler worn out probably causing excessive backpressure and heat...) before this I didnt have a backfiring problem. At night when I'm downshifting sometimes I think poeple are taking pictures of the back of my car...
Old 01-12-06, 07:59 AM
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When I did my rat's nest removal, I had a lot of backfiring.....It was a simple timing issue for me....
Old 01-12-06, 09:42 AM
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is there a thread on proper timing?????
Old 01-12-06, 12:13 PM
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OMG you guys are crazy!!!!!!!......
Old 01-12-06, 02:15 PM
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sometimes i think there a damn cop behind me (kinda scared me the first time).
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