I don't believe you'll have any choppiness to the idle, especially with the GM cam as the duration is shorter then the stock 350 300HP cam. The Howards cam has duration and LSA specs that are very close to the Summit K1102 flat tappet cam. I've found this YouTube video of a 355 with the K1102 cam idling. Actually, I like the exhaust note of this Camaro, has a nice rumble.