For anyone with exhaust problems or looking for more power this may help. My catalytic converters had begun to rattle and the resonator and last couple of feet of exhaust pipe were missing when I bought the truck. The rattling was getting worse so I took it to have it looked at it. I ended up having the cats hollowed out since I don't have emissions testing. They cut the existing pipe off and welded in a new Magnaflow muffler and pipe. Between removing the clogged internals of the cats and the high flow muffler I noticed a definite increase in power. The truck fires up instantly now. I also feel safer with the exhaust exiting all the way out the back instead of underneath the cargo area. I saved weight too as the whole exhaust system probably weighs half as much as the stock set up. All for $260.

 

No engine light? usually the computer don't like that and could create issues since there is no cats and the sensors have a false reading from the O2 sensors.

 

No. I don't know if it would effect it since I only have one O2 sensor per bank located before the cats. The newer models may be effected if you have 4 sensors, idk for sure though

 

Year if truck? Must be obd1, my cats are removed had to fool downstream o2

Think there's a discussion," lose the cats no codes"

 

Yeah it is, 95. I like the older design with the distributor. I was surprised it gave any power increase though.

 

Increase is probly only from removing the bad cats

 

 

Glad I found this thread - just picked up a 95 3.9l V8 with rattly cats and wasn't sure if straight pipe would throw any codes.

 

The cheapest way I found was using a local shop and having the exhaust custom built. The pre made mail order systems are much more expensive. Glad that helped you, and let us know how it comes out!

 

Thanks mate. I contacted a local shop yesterday and they reckon they can weld in the straight pipes pretty easily... will report back with results.