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Old 05-03-2018, 01:03 AM
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PeterAllen PeterAllen is offline
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Join Date: Jul 2011
Location: Sydney, NSW
Cobra Make, Engine: Puckett 250 GTO - LS1
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Quote:
Originally Posted by boxhead View Post
Will you be modifying glass and door frame too?
Yes. The original design was a bit of a failure and needed to be reworked, so that made the decision for the modification easy.

The original configuration had the base of the frame attached to the top of the door. At anything over 100 the pressure difference created by the airflow over the window pulled the frame away from car body as the lightweight fibreglass flexed at the base mounting points. The aluminium door cards added a bit of structural integrity but unfortunately not enough.

I now realise the secured legs of 'wind-up' window frames not only serve as guides for the glass when it is wound down, but also to counteract airflow forces over the glass when it is wound up. When I made the sliding windows I was unaware of that. Live and learn.

Funny thing is I modelled the window design of those of early 850 Minis, now everyone tells me they were notorious for flexing and letting the rain in!

I'm part way through making new frames with improved (?) base mounts.



Yellow = original
Blue = new

Last edited by PeterAllen; 05-03-2018 at 01:31 AM..
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