legacycentral bbs

so after custom making my own exhaust yesterday (couldn't get any exhaust shops here to do it)
i find my car with no cats, no o2 sensor, a nice clean straight pipe to the stock muffler..

i refabbed the y-pipe and eliminated the cat. its straight pipe now.. the 2nd cat is gone and straight piped as well..
stock muffler is still there.. would sound nice if it didn't have a loose baffle

exhaust does not smell even without cats, car revs to redline easy now..

i have no check engine light, and car runs fine without the o2 sensor..

should i go through the trouble to put it back into the system or just leave it out?

yes, you'll want that O2 sensor unless you like running super rich all the time. I doubt you'll pass emissions w/o one either.

The engine cannot accurately adjust the fuel trim without an oxygen sensor installed. You'll probably suffer a fuel economy drop too.

The O2 sensor only adjusts if something isn't running right. I ran without for a few months when I put my downpipe in and it ran exactly the same and I got the same exact gas mileage(though who knows what my emissions were like). It's a good idea to get one in just in case, but it'll run just fine without it, so it's not urgent.

If you're able to make your own exhaust it should be easy enough to weld a new bung on.

The O2 sensor is primarily used to adjust fuel trims under closed loop like when you're cruising on the freeway.

I'd strongly suggest putting one in.

no emissions here, or inspections, so cats and such are no problem to get rid of..

car only has 98k original miles, so everything is in excellent shape.. with the exception of the exhaust, lol..

i ordered a o2 bung today.. it'll be easy to install. lots of room in my custom y-pipe