Civic EG

Hey guys,

so i recently installed an "n1 styled" pipe onto my car, ive noticed that since ive had it, i basically pop and crack either A) when i pull hard and shift from second to third, or B) everytime i downshift. its a bit annoying and i never noticed it when my dad had a similar exhaust put into his eg coupe. does anyone have any reason why my cars doing this? Ive read on some forums that it could be unburned gas which is causing the poping noise, also read somewhere it could have something to do with my timing?

If anyone could shed some light for me, much appriciated!

(also, sorry if this is in the wrong section!!)

Thanks,
Nick[/list]

You ar correct about the unburnt fuel and timing. I would check the timing the proper way, using a timing gun, to be sure.

Thanks teal!

Could be timing. How frequently does it occur? If it isn't timing, you may just be backfiring a bit. When you open up the flow capabilities of any 4 cylinder 4 stroke engine, you allow the car to breath better and allow more air to be mixed with the fuel that burns in your engine (Assuming you are running a CAI ( Cold air intake)). Could possibly be that the air/fuel is too rich and when the exhaust valves open up, some un-burnt fuel is going into your exhaust system. Any charring / blackening around the outlet of the pipe? And what size piping are you running?

Just my $0.02. Just throwing it out there.

94 EG Hatch wrote:Could be timing. How frequently does it occur? If it isn't timing, you may just be backfiring a bit. When you open up the flow capabilities of any 4 cylinder 4 stroke engine, you allow the car to breath better and allow more air to be mixed with the fuel that burns in your engine (Assuming you are running a CAI ( Cold air intake)). Could possibly be that the air/fuel is too rich and when the exhaust valves open up, some un-burnt fuel is going into your exhaust system. Any charring / blackening around the outlet of the pipe? And what size piping are you running?

Just my $0.02. Just throwing it out there.

Tons of charing lol. its a 2.5 inlet with a 3.5 inch pipe. it happens like clockwork when i push it in second then shift to third. the sound also happens when downshifting in general. my mechanic said it couldnt be a timing issue, since my car is perfectly tuned timing. Is there a way to stop the air/fuel from being to rich? Does it matter what gas i use? I use 94 octane from chevron? Does that matter?

I'm assuming that this car is stock so 94 octane is not required for your car and there is no performance gain by switching to 94. If you just installed a pipe and there is no resonator this could be it since it is less restricive. Also an exhaust leak can cause a back fire.