I have a question about my current exhaust. I currently have a straight piped Flo Pro equipped. My buddy's dad have the identical truck, meaning same year, motor, tires, bumpers and of course tuner. Only difference is our exhaust brand and he has a intake system and I have a K&N air filter and his exhaust has the muffler, catalytic converter, and I don't. We went head to head on the highway and he pulled away from me, then we raced from a dead stop and same thing. He told me that it was because I don't have my catalytic converter, and if I did I'd get better results. Is this true, or does a air intake make that big of a difference? I've tried to figure this out, but can't find any info on diesel's without the catalytic convertor losing performance. Stupid question, but I'm so very curious on what the hell is up? FYI, I didn't get a late start on the race.. His truck just out right left me..

04' LB7
Quadzilla Stealth lvl 6.
4inch Flo Pro straight Pipe

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