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Hi guys I just wanted to ask a few things before I have my cats gutted.....if I just gut the cats and leave the cat there without replacing with a pipe will it affect the car or HP. I will say this after it is gutted it will be flashed and tuned on a dyno. The cost for the gutting of the cats and the tune will be about $1300. Good or bad on price? :dunno:
 

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A shop was going to gut my cats for $700 and then for the Alpha N tune from Evolve it may have been around $1300 for a total of $2000. So if you're getting that tune then i would yes thats a good price.
 

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Best way to gut the cats is take them off the engine and do it in a vice. They arnt easy to do.
All the sensors need to be taken out and you need to buy long drills. You need a sturdy vice and bench.

I used all sorts of tools, screw drivers, chisels, drills, flat wood drills, long nose pliers. Once you get a big chuck out its easier, most of the time you hammer away trying to break the stuff up. It took me 1 hour per cat on a bench. Dust gets everywhere.

I wouldnt like to do it with them on the car. And if you have a battery powered drill forget it, it will last 5 mins.
 

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I know a guy that had his drilled out. Some left over pieces that were not fully cleaned out got scavenged back into the combustion chamber and jacked up the valves.
 

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I know a guy that had his drilled out. Some left over pieces that were not fully cleaned out got scavenged back into the combustion chamber and jacked up the valves.
+1 do it the proper way and weld in a straight pipe
 

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I did it with this tool and a shop vac and I didn't remove the 2 upper O2 sensors there's something welded just after the sensors like a cage. I also used a air drill. First drop the whole exhaust and then start drilling.
 

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I did it with this tool and a shop vac and I didn't remove the 2 upper O2 sensors there's something welded just after the sensors like a cage. I also used a air drill. First drop the whole exhaust and then start drilling.
No cage in mine when I gutted them. Glad I took out the first O2 sensor otherwise I would have drilled through it. Once the drill goes through the Cat material you have no idea if its hitting O2 sensors or the wall.
 
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