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Old 09-16-2013, 07:48 PM   #172 (permalink)
christofoo
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Join Date: Mar 2012
Location: Salt Lake City
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00C - '00 Toyota Corolla
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Quote:
Originally Posted by euromodder View Post
...

Oh ...
You're only about 1 foot away from a full boattail ...
...
That's the idea - why close the gap between trunk and hitch box when it will almost certainly be more effective to close the gap between Kamm-roofline and hitch box?

I could spend more time tufting between the car and the box to try and figure out where the air is going and why... nothing jumps out at me as a sizable gap on the underside or sides... it may just be a recirculating vortex...

Quote:
Originally Posted by euromodder View Post
...

As for the angle on the bottom of the hitch-box, I seem to recall somebody used a hinged plate on the bottom of their boat tail.
At its lowest, it was at the optimal angle.
On a steep driveway, it'd just get pushed up.
A bumper or small wheel takes care of lifting the plate when needed while reversing.
That sounds an awful lot like this project here. IIRC the angle that the under-side of my box follows is right around 12 from horizontal - just a little faster than ideal.

I think the explanation for the turbulence underneath my tail is that the flow is not smooth when it leaves the bumper. I haven't done anything to the underbelly yet.

Quote:
Originally Posted by freebeard View Post
Stiff and tough because it will alligator open?

Consider putting it on a 4-bar linkage. Then it will be held at four points instead of two so it won't get racked so much. The lower arms would want to be about as long as the decklid and the upper ones shorter.

Then use the decklid to replace the two bottom bars.
I was about to dismiss, but actually it's a pretty interesting idea. It's a decent alternative to mine, which was using a pushrod to link the Kamm and trunk to move in unison. You end up with 3 lids, but I might be stuck there anyway, more or less.
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