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Backfiring

Primordial

By Primordial,
in Engines & Forced Induction

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frankxinyu Mentor

frankxinyu

Posted
Posted
PEOPLE PEOPLE!!!!

can we please get the term right

AFTER-FIRE

AFTER-FIRE

AFTER-FIRE

back fire is where you get flames out of your INTAKE

thanksyou ;)

what??

obn topic, i am running the stock BOVs, with PFC, and a safe tune on it. mine backfires quite a bit. it even throws flames sometimes at high rpm. i believe it is quite safe, it is just running a tiny bit rich.

Primordial Grand Master

Primordial

Posted
  • Author
Posted
PEOPLE PEOPLE!!!!

can we please get the term right

AFTER-FIRE

AFTER-FIRE

AFTER-FIRE

back fire is where you get flames out of your INTAKE

thanksyou :)

Technically correct, thanks.

How many people would know what afterfire is though? :happy:

The Alchemist Collaborator

The Alchemist

Posted
Posted

personally I like a good backfire on a gearchange or decel but " hey" thats just me :yes:

If you find it a problem there are a couple of things you can change on your PFC settings to remove or lessen the effect.

Firstly your accel pump settings are set quite high from factory with the PFC. So any slight blip on the throttle pumps in a fuel but little air. This hits the hot exhaust with the usual pop pop crack sound. You can even "make" it do it on a trailing throttle by tapping the throttle lightly on decel.

Dropping these accel back from the 4 or 5 ms factory down to 2 or 3ms improves things.

Secondly the bottom fuel row settings have a big effect on trailing throttle overrun and can by reduced (carefully) to reduce exhaust popping. The PFC does have fuel cut on overrun I know but these bottom row settings do have an effect.

Cheers,

Mike

Primordial Grand Master

Primordial

Posted
  • Author
Posted
You can even "make" it do it on a trailing throttle by tapping the throttle lightly on decel.

Hahaha... this is exactly how i've been scaring unsuspecting pedestrians :yes:

Thanks Mike, great info!

I'll give this a try :P

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