2 questions

[fuel110]

1st question: sometimes when i let off the throttle i get a loud backfire, (ppl start ducking and looking for terrorist) I only notice it when i'm running strait pipes, I plumb it back through the stock exhaust i don't notice it. why does it backfire, is it a problem?

2nd question: Just had her chipped, what plugs should i run, what heat range, and what's the gap?

thanks for any support!
Torrey

[NYBugman]

1) no muffler means you hear every sound there is to come out of your exhaust. Plus, the decrease in backpressure from the muffler can alter your mixture, which the ECU will compensate for eventually. It's not a bad thing, but it's more noise.

2) Run NGK BK7RE gapped at .028, IIRC. The 7RE is one step colder than OEM and recommended for use on a chipped car.

[fuel110]

thanx

[Billsbug]

Yeah, years ago after getting chip & tb exhaust, I called my tuner shop about this, they said it's just extra fuel igniting as it leaves the exhaust. Fun for scaring old ladies.

[fuel110]

i was driving through the bad part of town when this first happened. (no joke) scared the bejeebies out of me.

[fuel110]

what's the difference in the denso ik22/5304 and the ik22/5310 ?