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Doc, my new Road King arrives soon, and I’m looking to fitting a Screamin’ Eagle Heavy Breather air cleaner, V&H Big Oval mufflers and maybe SE255 cams and a SE tuner. I’m not trying to turn it into a V-Rod, I just want a crisper motor for towing a trailer. Would a Stage One 110ci kit be better value? Is there much to be gained from replacing the exhaust pipes to remove the catalytic converter? I’ve been told this will help the motor run cooler.

– Whiskers

Whiskers, you should get a significant performance increase with the mods you suggest. I wouldn’t bother going to 110 because that is a pretty expensive route. A freer-breathing exhaust such as the S&S Power Tune Duals header pipes and 4in Slash Down Race Tour mufflers should help a bit with cooling but have a look at the questions on hot running TCs further down.

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