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ny-s14blacktop
03-21-2006, 07:30 AM
I have a 96 nissan 240sx in the great state of new york and have the s14 sr20det vvt blacktop engine with a greddy intercooler, greddy bov, greddy boost controller, greddy down pipe , custom 3 inch exaust all the way back and some other stuff but not worth noting. My problem or question is that my car backfires a lot and loud like a gunshot, I stay scaring the shit out of the homies down the blok but I am wondering if this is normal or causing damage, it seems to me like it happens when I get on it then drive normal pop, could this be b/c of my free flowing exaust, and is it hurting my car and how do you fix this
neverlift
03-21-2006, 07:46 AM
my sohc ka does this sometimes,a friend told me it was detonation or timming,what octane gas do you run?
ryangreg
03-21-2006, 08:23 AM
Man, its that BOV you have venting to atmosphere. Do a quick search and you'll find plenty of shit.
sr20newb
03-21-2006, 08:32 AM
Is it only backfiring when you first drive it? or even after it warms up?
aznpoopy
03-21-2006, 08:39 AM
if you have your bov and maf set up like 99% of people... then yeah. turbo blows air. air is metered. throttle closes, bov opens (goes pssh). the car already injected fuel for that air that never made it into the cylinder. result? car runs rich between shifts and you get a pop or a bang out the exhaust
neverlift
03-21-2006, 10:49 AM
sorry bout jacking thread,but what about na ka?
ny-s14blacktop
03-21-2006, 11:17 AM
I run premium and it happens after the throttle was 100%, then I drive normal and then I get a backfire
smithers584
03-21-2006, 03:47 PM
what are you using to tune your fuel? have you got your A/F ratio dialed in correctly? if not, you are just running rich, thats all a backfire is usually. maybe one of your sensors is bad and causing it to run rich, maybe you need to tell us more about your car and its history. Its hard to tell you without knowing these types of things and what you have tried to do to troubleshoot it. its definately not due to your "free flowing exhaust".
smithers584
03-21-2006, 03:52 PM
if you have your bov and maf set up like 99% of people... then yeah. turbo blows air. air is metered. throttle closes, bov opens (goes pssh). the car already injected fuel for that air that never made it into the cylinder. result? car runs rich between shifts and you get a pop or a bang out the exhaust

so are you saying it would be more accurate with a blow through MAF located on your cold pipe right before your TB? my buddy went that route, but i havent had any problems and i usually do not hear any backfiring with mine mounted after the filter.