Tim Werner has done 160mph in his Valiant at Willow Springs and Portland, but that car runs a chin spoiler and has lots of other modifications...
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This Duster runs the Australian Trans Am series (chin spoiler, wing)
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Not really. These cars were not designed for sustained speeds over 100 mph. Their inset grilles, relatively large frontal areas and bodywork that sits well above the ground all mean that at higher speeds the front end tends to lift, which makes the front end light and squirrely.
If you want to keep the nose down you have to reduce the amount of air going under the front of the car.
Yes, there are lots of E-bodies built for that kind of speed!
T/A cars...
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Jess Neal's Pike's peak car...
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Australian Trans AM 'Cuda competitor
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And look, more T/A cars. Notice something the ALL have in common, even across different makes and models?
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That's right, they're all sporting large chin spoilers and rear wings of some kind. It's almost like '70's musclecars weren't designed to do 150 mph without modifications...
Speaking of which, other than some QA1 parts and a sway bar, what does the rest of your suspension set up look like? Because again, you're not going to do 150 mph in a '71 Duster safely and reliably without a lot of modifications to the suspension and bodywork.
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