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Rear gear? you are in 3rd gear at 6 grand. 13" wheels?

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Honey anyone?

Hi BW,
Yes, 13" wheels with 23" diameter rear tires. The diff has 5.38 gears so that third is the AutoX gear.

Weight reduction effort continued by replacing the 12 gallon fuel cell (JAZ plastic tank in steel can) with a 3 gallon aluminum tank. Shaved 20 pounds.

In the interest of better performance though, I added 5 pounds by removing the 10 lb aluminum spoiler and replacing it with a 15 lb carbon fiber wing/metal supports.
I made the individual elements by doing wet layup over pink foam pieces cut using Nichrome wire/2-amp battery charger.
Layers of CF fabric were laid out on plastic sheet and saturated with epoxy resin and squeegeeing. After 2 layers, another layer of plastic was laid on top and with a dry squeegee, the entire area could be worked to get complete saturation and air void removal. Two such layups were made for each element and then they were draped over the foam core. The short elements were hung for curing, while the long elements had to be placed horizontally in the companion section of foam that had been pre-covered with packing tape (the epoxy doesn't stick to it). The resin had a 6-7 hour pot life, but I only mixed enough resin to do the element that was being done.
After two days curing, the edges were trimmed and aluminum side inserts with rivnuts were epoxied inplace. The inserts were hammer formed over wing profile oak mandrels.
Premade CF panels were used to join the sections including the provision to adjust the second elements. The side panels were painted and the wing elements were wrapped with vinyl.
We had our last AutoX last weekend and I was pleased with the first outing. The seat-of-the-pants impression was that it was more planted everywhere. The datalogger indicted that in the sweepers (35 to 40 mph) where 1.5g had been the norm, 1.6 to 1.65g was experienced. There was one point at 1.7g.

https://youtu.be/Nr6l67hi0rU


OK, now back to more lightness.

That's quite a spoiler system. Very impressive - the technique too.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Weight reduction update:
In the last few months many items have received attention. The engine belly pan was reduced in thickness from 0.120" to 0.060". The dry sump plate was redone in aluminum from the previous steel plate. The door posts were cut off and replaced by aluminum channel posts with aluminum nut plates for the hinges. The radiator size was reduced as well as changing from a dual pusher fan to a single puller fan. The stock FC front rotors were replaced by some thinner Willwood sprint car ones along with some DIY aluminum hats. Lightening holes were drilled in the A-pillars. The wing support stands were revised.
The net result is that the car now weighs 1780 lbs. (much better, but still need to do more)

You could cut out the rear panel between the fenders, wing, and roll panel to fit a black mesh, supported with one inch ribs formed from .050 3003. Hang the same or universal round hella tail lamps.

Fab front uprights with minimum offset hat and floating caliper to move the LBJ out for reduced scrub and weight.

Pull a mold of the front clip for a one-piece to remove all that hardware and ribs holding the panels in place.

Oven mold acrylic for the rear side glass on a wood form?

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

MV8,
Thanks for all the good suggestions. The only one that I balk at is the one-piece front end. My experience with one on a GT3 car was the need for two people to remove/install and the large area needed to set it when removed with the occasional windy day consideration.

After all of the work, I have some interesting test results and a report from the latest autoX.
A friend (who is into aerodynamics), questioned the angle of the second element and gap on the rear wing. He suggested some tuft testing to see if the air was really attached to the under/backside of the wing. So, I taped tufts on the end and middle elements of the wing and first did a stationary box fan test. The first pic shows the tufts being "attached" to the end element section with the fan blowing horizontally.
The next pic is a screen shot from the GoPro video with the car on the trailer going 55 mph into an 8 mph headwind. It was interesting that the video shows the attachment forming at 25 mph. My friend is satisfied that the wing design is acceptable .
At the autoX yesterday, the afternoon temps (63F) and clear sky resulted in the pavement warming up enough for the rear tires to develop temps in the 85-95F range. There were a couple of places that allowed WOT use so that the car could stretch it's legs. The aero downforce at the speeds reached made the car very stable in the ensuing turns. There were several locations where cornering g's of 1.64-1.71 were experienced.
My placement in the overall results of 8th was the first time in many years that I've been in the top 10. The last time was when this engine was in the Caterham.

The video from the best run:

https://youtu.be/p-6bMJFiHGc

Legendary status unlocked. Congrats on the crispness of that run.

Thank you KinRe.

A local drift group is now organizing a Time Attack series. A relaxed first event test-and-tune was conducted yesterday at short oval track that just added infield sections for such events. The two rules for cars to be entered are: must have been registered for street use at some time and the tires have to be 200 treadwear rated. Since the RX7 complies, I attended. They have more events scheduled this year at different tracks (all small ovals).

https://youtu.be/aRIrGHM2oG8