Top speed G bodies/ bonneville cars

[custom442]

This thread is to help my curiosity of building a top speed G body. I've seen guys on here state their cars can get up to around 180-200 mph. So the question is, if we were taking our cars to the salt flats, what are tips and tricks we'd use to get to those top speeds. Also what kind of power and gearing would it take to hit, lets say, 160 mph vs. 180 vs. 200 mph.

I'm just toying with the idea, I've got no intention of putting all my effort and budget into a top speed type car. But since I have what I believe is around a 2.14 rear in my car with a good engine, I might take it to a standing mile around these parts to see how it'd run before I swap the rear in about 30 years . Just somethin fun to think about.

 

[jrm81bu]

This is something I would love to get in to more. Ever here of the Silver State Challenge?

My old Malibu hit 170 mph at 6000 rpm......on the chassis dyno.

According to my calculations and guessing alittle for convertor slippage, I'd say i've ran 150mph on he street.
If I had enough room and balls, it Might have made it to 160.

Trying to go much more than that will require a good chunk of extra power to get near the 180 mark. These cars are nowhere near ideal to run that fast. Hittin around 150 is like running into a wall..of air.

 

[axisg]

yeah, the car is not designed to go that fast. It's too boxy and tends to get very light at higher speeds. You would want a Monte SS or GP2+2 slammed to the ground to get it up to any speed IMO

 

[dogsht]

Was thinking the same thing MCSS Aerocoupe or GP 2+2 or kit or at least 87/88 Cutlass with Euroheader. At least a 1 1/12" drop. Front lower spoiler & or kit from Laurenengineering. Functional rear spoiler / fin. Remove badges trim mirros antenna etc etc. Lots to do that become just as important as more power. I think above around 160 for a stock bodied G it becomes exceedingly involved to move up every single mph.

 

[85 Cutlass Brougham]

The biggest issue, even with an Aerocoupe or GP 2+2 is that there are lots of aerodynamic issues to attend to, the biggest of which is the side windows. They are far from flush, and the side windows tend to want to pop out when it gets going really fast. Plus, you will need to retain the rear window with more than just glue lest it be sucked out with the aerodynamic forces at those speeds. Can a G body reach 200+ MPH? Sure, an Aerocoupe NASCAR stocker with the right gears and no restrictor could have hit it back in the 80's. Theoretically if you found an old stock car and put enough power and gearing in it you could run the number. I would think no less than 650-700hp would be needed. I would also build the engine for high RPMs so that you have enough head room to wind it out.

The easiest car to start with if you wanted to do this would probably be the original Honda Insight. It was the most aerodynamically efficient car ever made. The shape is rather unusual, almost like another highly aerodynamic, revolutionary car, the Citroen DS. Insights are getting pretty cheap now too as the hybrid crap dies and repair becomes too expensive (much like Citroen hydraulics!). There is a following for them, just like any unique car, but not enough to make them expensive. Run it with a tube chassis and RWD with a good 4 or V6 engine and you would have a contender.