friend up the street from me has a '72 (?) cutlass. he had a 496 in it and did some 11:20"s (he may have snuck a couple teens in there) at 123mph, thru the mufflers and pump gas. it has edelbrock heads with serious work, torker intake , AED carb, hydraulic roller, 3.73 rear, turbo 400. it's set up for a bottle but don't think he has any times with n2o. full interior; bet it's at least 3700lbs. think it dynoed 575+hp. currently has a 540 in it, dynoed 670hp. no good times yet with the 540. i would think some kind of power adder would be needed to get into the nines with full street trim. it does take some money to get big performance from these cars, but they can be impressive. i don't think it makes any difference which brand they are you can make those old in-line valve dinosaurs run'