FS/AA vs FS/XX

bsimms89 · 04-30-2019, 02:29 PM

The engine combo's currently used in the shootout are "legal" in stock but many of them are rated at a hp that put the car over the maximum allowed weight of 3,600lbs for an SFI25.5 7.5 second cage. for example the 2016-2018 COPO were delivered with a 350 with the whipple rated at 580 hp (currently factored to 617), but the rulebook also allowed a 590hp version(currently factored to 630hp) the difference between the two included superharger puller size, rocker ratio difference, and some valvetrain stuff. In the 2019+ COPO's they come with a 600hp rated 350 with the magnuson, or there is a 630hp verison also in the rulebook, again just different pulleys and rocker ratios.

With the current weight break of 5.5 in FS/AA once a combination is rated over 623hp the car will be over 3600lbs, the specs for the 7.5 second cage is limited to cars under 3,600lbs. Based on the rules you can run the higher rated shootout motors in FS/AA but it would put you over 3,600lbs so you wouldn't be permitted to make a run faster than 8.5 seconds because the cages aren't certified to 7.5 seconds at those weights.

04-30-2019, 02:29 PM	#7
bsimms89 Junior Member Join Date: Jun 2012 Location: Long Island, NY Posts: 70 Likes: 29 Liked 70 Times in 19 Posts	Re: FS/AA vs FS/XX The engine combo's currently used in the shootout are "legal" in stock but many of them are rated at a hp that put the car over the maximum allowed weight of 3,600lbs for an SFI25.5 7.5 second cage. for example the 2016-2018 COPO were delivered with a 350 with the whipple rated at 580 hp (currently factored to 617), but the rulebook also allowed a 590hp version(currently factored to 630hp) the difference between the two included superharger puller size, rocker ratio difference, and some valvetrain stuff. In the 2019+ COPO's they come with a 600hp rated 350 with the magnuson, or there is a 630hp verison also in the rulebook, again just different pulleys and rocker ratios. With the current weight break of 5.5 in FS/AA once a combination is rated over 623hp the car will be over 3600lbs, the specs for the 7.5 second cage is limited to cars under 3,600lbs. Based on the rules you can run the higher rated shootout motors in FS/AA but it would put you over 3,600lbs so you wouldn't be permitted to make a run faster than 8.5 seconds because the cages aren't certified to 7.5 seconds at those weights. Last edited by bsimms89; 04-30-2019 at 02:55 PM.