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Pacemaker make 2 different sets of VR extractors, standard 1 1/2" primaries and performance 1 5/8" primaries. People make the mistake of fitting the bigger ones because they think it will give them more power, where the opposite is true, you need the power first to take advantage of the bigger size. The Pacemakers give you more top end because of their flow design. Whichever way you go, I don't think it will be noticeable unless you dyno it.
Whatever fits your budget. I prefer pacemaker. Some people will tell you Genie are the way to go. At the end of the day, all extractors do pretty much the same job on a stock street car.