IF those times are legit, then my 350 GS making MORE power than the fabled BBC in the ‘Vette being my GS is 300 lbs heavier, and I’m sure the Corvette tested had deeper gears than my 3.42
Density Altitude is one of the most critical of all pre-takeoff calculations. You are comparing present conditions with what is called a "standard day." A standard day is an Air Temperature of 59 degrees Fahrenheit or 15 degrees Centigrade, with a barometric pressure of 29.92 inches of Mercury measured at sea level. If you raise the air temperature, the air becomes less dense and your density altitude increases; you will use more then the "normal" length of runway for your gross weight. The same is true if the barometric pressure decreases. There is a reason why the main runway at Albuquerque International Airport is 14,400 feet long. If you have a barometer that is not corrected to sea level, the normal barometric pressure at Albuquerque is about 24 inches of mercury. Long takeoffs are the norm there. Quite a few years ago I watched a DC-8 take off at ABQ, it had about 50 feet of altitude in the bank at the runway's end - maybe not quite 50 feet. Since your engine does not know what it is attached to, density altitude will affect your car's power exactly the same way. The entire purpose of a supercharger is to increase the engine's density altitude. Increase in the sense of making the air more dense.
Deeper gears, most likely you are correct. I think the options from Chevy are 3.90 or 4.10 gears. You bring up a point, most of the et & mph times don't give you what differential the car is using. A PURE stock factory car can have all kinds of performance add-on's. Makes me wonder why Chevy build two 4-speeds, M20 & M21?
Mark, you'll like this one. I was on YouTube yesterday and saw an interview with a guy that that built a 1970 GSX tribute Skylark (great job too). He was asked if the 455 is original to the car, he said no, it's a 1976 455. The guy asked him about the heads. The guy said they are aluminum Buick factory heads. A very limited build he said. WHAT!!! Have you ever heard of Buick making limited or experimental aluminum heads for a 455? I never have. VET
To the owner of the GSX it IS a limited build It never ceases to amaze me how people like to embellish on their cars like everyone is stupid. It’s the same as a Turbo Buick guy saying “yeah its the twin turbo GN” Lolol, THAT NEVER happened either!
Just the other week my wife told me about her coworker who said she had a uncle with a twin-turbo Grand National. Something about buying it brand new and driving from the showroom floor to the track and running 11's with it. She said he said it would've run 10's easy, but he wasn't trying hard because it was still new. Apparently it was stolen after winning all of the street races in town.
