HAT3R 671

i got a 04 wrx w/ TBE, up-pipe, turbo XS RFL BOV, and stage 2 cobb AP.

my car backfire usually after i let off the throttle and coast. it sounds like there's a m-80 in my muffler. im thinking the BOV is letting my car run rich, but that shouldn't be the cause of the backfiring, right? i thought if it runs lean it'll backfire. is it bad for my motor to be backfiring like that all day long?

please help a noobie with a subie!!

ipozestu

iTrader: (18)

Get rid of the BOV. That is what is causing your problem.

Isn't this one of the FAQs?

The back firing is caused by unburnt fuel igniting in the exhaust gas path. It's pretty much harmless. The big problem is the BOV. You are killing your performance. Put the stock one back on or get a BPV like a Forge or something that will recirc 100%. That's the way it's supposed to work dont' F with it.

HAT3R 671

^^^^ thanks i'll try it out

EBTurbo

Do you know how Anti-lag(misfiring system) or a 2 step rev limiter works? cut the ignition let the fuel get burnt in the exhaust, causing the turbo to spool. when the pop-off valve prevents the turbo from compressor surging the exhaust misfire will actually spool the turbo helping get back to full boost sooner after a throttle plate close(shift or lift). when you do have open atmosphere BOV's they tend to stay open at idle causing a massive vacuum leak. poor idle quality, poor fuel economy, etc. this issue can be argued all night long, there is no right or wrong way to do it. just another way to look at it.

EB Turbo

VRT Gump

iTrader: (4)

no matter the reason, if you are catless with a BOV you will shoot flames. If you dont want to shoot flames, put the stock BPV back on.

EBTurbo

the stock BOV is not 100% no flames but you might get one on hard upshifts. but its about 95% gone.

EB Turbo

tofuman

iTrader: (31)

^+1. Catless with BOV, you're guaranteed flamethrower status. Don't get me wrong, I think its fun and the BOV sounds great... but IMO get rid of the BOV. Your stock BPV is good up to 300+HP and less of a headache to deal with. (And there's less of a chance of Officer Importhater pulling you over for flaming and giving you a fix-it ticket and/or decide to be a d**k and have you pop the hood to find more "illegal" mods so he can have it impounded. If you like the "whoosh" sound, do the airbox mod or get a CAI and you'll be able to hear the BPV on your shifts.

sigma pi

iTrader: (6)

it takes more than that to make anti lag to work properly

EBTurbo

Care to share??
there are many other ways to do it, thats just one example.

EB Turbo

sigma pi

iTrader: (6)

yeah you run the suck push but you dont bang it you blow it out then on the blow you ignight the fuel and air mixture. the gas expands and the WG is held shut.

during this the throttle is held open 15% tps or soemthing around that.

you need a solinoid and no BOV set up to run it properly.


now can you run it improperly and jsut do the turn teh plug off and then ignite on the exhuast stroke? of coarse but you wont be getting the most out of the damage you are doing to your motor


but anti lag is sweet as hell haha

VRT MBasile

iTrader: (17)

technically what you are getting is after-fire. It happens as the heated unburnt fuel meets the oxygen in the air. A backfire is really bad and I believe occurs in the intake.