Recently I had Flow Tech headers, dual exhaust and Flow Master mufflers installed on my 92 w/ 302. The engine is stock except for the exhaust. I've had it back to the shop that installed the duals for a couple different problems. (Banging on cross members, rattles and passenger side header bolts would not stay tight. Those issues are resolve but worse is the performance. The O2 sensor was tapped into the crossover (H-Pipe) in order to keep the computer happy, but the engine power is so poor that it's almost not worth driving. The engine is constantly backfiring under acceleration and deceleration. It was suggested that I remove power to reset the computer. Tried that for about 10 minutes, but no change. I've had the power off for the day and am about to try again to see if it helped. Not holding my breath.<br><br>This is a strong engine so I know I don't have any other engine issues going on. The reason for the change was the original Y-Pipe had rusted through and I could not find a decent one without going to Ford and they wanted upwards of $700.<br><br>Anyone had a similar experience? Any help would be great. I'm tired of driving back and forth to this shop and I'm close to taking it to another shop to have the stock exhaust installed and dealing with them later on the money I've already paid for the new exhaust.<br><br>Thanks in advance.

Don't tkae this too seriously because I'm not too sure about this, but here's my 2 cents worth. I think that it might help if the O2 sensor was right in the flow of one of the main pipes instead of in the H-pipe-just a guess though. I ran my motor with no o2 sensor for a good little while but that motor has since died. See "Re:New Member Introduction" for more info on that motor. Another thing that could be a problem is that the pipes could be too big- what size are they? I used to know a guy with a '90 Bronco with an exhaust similiar to yours and he didn't have this problem.

I have the Flowtech smog legal ceramic headers on my 89 with a 351. My rig has 192k miles on it so I have been trying to get all the performance out of it before i do a rebuild this winter. I have a flowmaster with dual exits and everything has been just fine... Maybe your truck does not have enough backpressure? Have you tried using a code reader and seeing if the computer is happy?

o2 sensor has to be in the main exhaust stream BEFORE the air injection port. the sensor at the h-pipe has no flow. does this engine have 2 sensors? if so, one on each pipe. If only one injector you need a y-pipe.This is why ford uses a single pipe through to the converter so the sensor can sniff all the exhaust. I dont know if a single sensor can be converted to dual sensors.