Monte Carlo CG Height?

[redss86]

Does anybody have any idea as to the cg height of an 86 Monte Carlo SS? Any and all help is appreciated.

Thanks,
Joe

[Norm Peterson]

SAE Report 1999-01-1336 lists the CG height for the generally similar 1978 LeMans at approximately 21.5" (the report is metric). The powertrain appears to have been the 3.8L carb'ed engine based on the "A" in the VIN provided, though I doubt that the 305 (or most any replacement) in the SS would make much difference in that number (the CG heights of front mounted engines by themselves aren't that much different from the whole-vehicle CG heights).

Norm

[redss86]

Also, if the car is lowered, does the cg drop equally with the lowering? Or does it change totally? Of course if it isn't an equal front/ rear drop, then I would think it is going to be totally different. Correct? Example: 2" front and 1.5" rear= ?cg

Joe

[Norm Peterson]

Not quite equally. The unsprung mass (wheels, tires, brakes, axle, etc.) does not drop, so the total CG lowering is slightly less than the visible amount of chassis drop. If the front and rear drops are unequal, there's a bit more math involved. Assuming 56/44 weight distribution and 500# sprung mass out of a total of 3500#, the overall CG drops by about 1.5" if lowered in accordance with your 2"/1.5" scheme. It is entirely by coincidence that it is numerically this close to the rear drop given in this example.

Approximate drop of the chassis at the fore/aft CG location =>
1.5" + (2.0" - 1.5")*0.56 = 1.78"

Approximate total CG drop after considering non-moving unsprung weight effects =>
1.78" * (3500-500)/3500 = 1.53"

That puts the CG at about 20" above grade.

Norm

[redss86]

Thanks for the help Norm

Joe