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Old 01-24-2017, 11:47 AM   #91
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And remember due to Bernoulli the lowest pressure is at the location of highest velocity. By the time the flow diffuses in the back the pressure comes back to ambient.
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Old 01-24-2017, 01:09 PM   #92
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Thanks a lot!

I am glad you mention it. I am still unsure if it would be better to open the wheel arches or to open the rear above the diffuser more... With the last argument I could maybe profit from the low pressure area at the trunk.

More opinions on this?
I would mount the motor fan on the diffuser "ramp" to suck air from inside and blow it out. A blown diffuser.
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Old 01-25-2017, 09:33 AM   #93
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That is how it looks. Right now I am not fully satisfied. I am happy that the double floor principle adapts into the Xray T4'15 chassis and happy about the look.
For the full vacuum effect the lexanfloor just isn't stiff enough. At some speed the air will pull the wings and diffuser to the ground which limits the overall pull down. Additionally the whole assembly is heavy. The car is 38gr. above minimum weight. To make it perfect a carbon frame should support a 0.3 or 0.5 thin lexansheet. The attachment hubs should be aluminium parts, small and strong. The rear diffuser needs support to prevent it from bending down rearwards from the vacuum.
Nice Work!!!
Did you tryed Kydex material...?
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Old 01-26-2017, 05:20 AM   #94
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That's DTM-ish mod. Awesome!
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Old 01-26-2017, 01:44 PM   #95
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To be honest: I never heard of Kydex before. I will take a look at it soon.
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Old 01-28-2017, 12:55 PM   #96
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The second test day is over.
Again I am not fully satisfied, but this time I at least have a smile on my face.
As we already determined the floor and its mounts is to weak to resist and lead the forces into the suspension. At speeds of 30 km/h and above the floor pulls it self down in a way that it rubs on the ground and slows the car.

I was forced to support the skirt-part and diffuser. I couldn't use the Dodge Dart body and drove without it. The balance was shifted strongly to the rear, but I could push the car in a normal riddim which speaks for a functioning airflow under the car.

Under the shower my brain developed a new strong rubfree floor. Lexan quota will be reduced and cfk will be used more. I am still not sure if a sealed double chassis has an advantage over an normal sealed floor. The latter is much easier to implement and build.
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Old 02-09-2017, 03:36 AM   #97
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I finished the carbon brace already I have too much other work right now. The wing part made from 0.5mm thick Lexan unfortunately wasn't straight after glueing with Shoegoo. So I have to do it again
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Old 02-09-2017, 04:16 AM   #98
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Nice, great to hear the updates. I still have a bunch of this on my to do list, but with overtime at work I just don't have the time now to implement all my thoughts. It's great to hear of your progress, I'm really looking forward to messing around with this.
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Old 02-09-2017, 12:18 PM   #99
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Cool. Please join us with pictures.
The more the merrier!

Edit: Some pictures of my floor part. It is the central part of many as it will carry the wings & skirts, the rear diffuser and the front splitter. That way I can change parts in case they get damaged.




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Old 02-10-2017, 11:01 AM   #100
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Found some time to build the wings again.
This time I made sure that it will stay straight.
I tore of the old tweaked wings and was surprised how strong Shoegoo holds this Lexan together. I needed around twenty kilogram force to pull the 90 degree positioned sheets apart

For the rebuild (I cut new parts) I used this shown method to ensure the sheets are positioned perfectly and then glued them from both sides to prevent the drying Shoegoo from pulling the sheet to one side (like before).



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Old 02-10-2017, 11:04 AM   #101
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Wow that's a lot of force!! Way more than I would have expected. Good to know it works so well!
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Old 02-10-2017, 02:47 PM   #102
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Quote:
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Did I say two days... I meant one day
Suddenly I finished everything. Let the pictures talk:















That is how it looks. Right now I am not fully satisfied. I am happy that the double floor principle adapts into the Xray T4'15 chassis and happy about the look.
For the full vacuum effect the lexanfloor just isn't stiff enough. At some speed the air will pull the wings and diffuser to the ground which limits the overall pull down. Additionally the whole assembly is heavy. The car is 38gr. above minimum weight. To make it perfect a carbon frame should support a 0.3 or 0.5 thin lexansheet. The attachment hubs should be aluminium parts, small and strong. The rear diffuser needs support to prevent it from bending down rearwards from the vacuum.
This is amazing. :-)
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Old 02-11-2017, 08:55 AM   #103
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Another day gone. The floor makes progress. Today the other side of the wings were formed and glued. This alone took several hours. Now I have to wait for the Shoegoo to dry. In the meantime I build the other aerodynamic parts like the diffuser and the front splitter. Many small parts like the mounts for the carbon brace also needed attention. Luckily most builds worked fine.
I gave up on thermoforming as the results are always catastrophic. But I dicovered that you can form the Lexan in room temperature conditions if you have a little feeling in your hands. As you see in the pictures the added parts (to the brace) are attached in a way that no edge is generated for the air. The brace itself is located at the upper level of the chassis plate creating a step. This is not perfect for the air stream, but gives the much needed ground clearance if the car leans in a corner.
Now some pictures of tha actual situation:









Still much to do:
The diffuser needs skirts, the carbon brace must be sealed to the chassis plate, the chassis plate will get a sticker to close the holes, then the wings will be attached and and will also receive skirts.
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Old 02-14-2017, 09:48 AM   #104
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Again an update from my side.
The parts for the tray are all finished and ready to be attached to the car. I did some minor changes to the carbon brace and the wing/skirt sections to reduce weight and optimize the dimensions.
Right now the shown assembly weights in at 55grams. For comparison the second floor came at 145grams and was weaker overall. So that is quite an improvement





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Old 02-15-2017, 02:45 AM   #105
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Looking forward to lap times comparisons now
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