Both bad catalytic converter would it be a good idea to straight pipe the whole thing
Sure, as long as you get new catalytic converters to go with your “straight pipes”.
Sure, as long as you don’t live in a country where catalytic converters are required by law.
If you live in The US, no reputable repair shop will put itself in danger of a large fine from the EPA for facilitating that type of violation.
Also, your ECM might have some problems in regulating engine function if there are no O2 sensors.
Please don’t, you’ll put out 10x the pollution. Don’t be a jerk.
Don’t go to the Lexus dealer for this.
Try a local muffler shop. You might be surprised how much cheaper they are than the dealer. It’s worth a try.
I won’t go into what the other guys said, although I agree with them. You should also look into why the catalytic converters failed. 13 years seems awfully soon to replace them. I’ve never had to replace mine, and have had cars longer that that. I am concerned that you will put the new converters in and in a few short years be in the same spot.
I’m curious. Is there a reason you’re asking to replace the existing converter with a straight pipe?
I ask because it’s illegal in the USA as previously noted, and perhaps elsewhere.
Where do you live? If it’s in the USA, does your state have emission checks?