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Dave Tabor
09-22-2022, 11:39 PM
Got this from forum member Fbird.

Cut it into 3 pieces to save 3/4 the cost of shipping- high-level math here and sacrilegious to cut this thing up- fit in a small box, lol. Seems like everyone has an old purple towel to wrap stuff up in.

Back together, here is what is looks like on the car- no splitter, just the bumper. There was a question in another thread about how far the hood opens.

My frame to ground ride height is 4". The bottom edge of the bumper is also 4" from the ground.

From the pics I'd say you could perform some routine fluid-type checks on the motor but not really wrench on it.

I'll eventually add a splitter (likely cheap plywood like luan- annoying that the bottom of bumper is not totally flat across - higher in the center- looks cool, but...).

In the autocross pic it was just taped on with Gorilla Tape- drove to and from the venue like that- no issues. I then painted it with Summit single stage urethane Wimbledon white- it's blue now, though- got bored this afternoon.

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Dzus fittings make it quickly removable.

I'd say this is a track-only item. It will hit stuff on the street and damage itself and perhaps the nose and it's mountings.

I'll try it at the drags and HPDE at Sonoma Raceway in two weeks (back to back testing with data)- I expect zero differences but it's something to do.

Dave
Gen III Coupe #17

Skuzzy
09-23-2022, 06:36 AM
At high speeds it should help reduce front end lift. It should act as an air dam forcing air around the front of the car instead of under it, especially outside of the fog lamps where the body curves under, quite a bit.

Then again, it may not be noticeable until you get over 120MPH (arbitrary guess).

J R Jones
09-23-2022, 09:36 AM
I have read about aero development at Porsche and their understanding is a balance exists between front and rear. Therefore a change of this magnitude in front is likely to change the dynamics at the rear. The drag strip may show a change in total drag. On the road course you should be attentive to potential change in grip and high speed stability at the rear.
jim

racingandfishing
09-23-2022, 12:34 PM
https://www.factoryfive.com/whats-new/gen-3-type-65-coupe-r-aero-testing-report/

rhk118
09-23-2022, 01:39 PM
https://www.factoryfive.com/whats-new/gen-3-type-65-coupe-r-aero-testing-report/

Good to read this once again.

Dave - great fiberglass work! Looks great....how long before you add a wing to her? :D

drewr
09-23-2022, 03:10 PM
That autocross picture is badass.

Dave Tabor
09-25-2022, 09:21 AM
I don't expect anything except maybe increased oversteer if the aero bumper reduces lift at the nose- so a wing is at least in my thoughts- probably should start with a wing, then nose or both at the same time.

That FFR report on John George's old car need data- I need numbers- lbs of downforce, drag and the like.


http://www.johngeorgeracing.com/

There are sites that sell wings that list drag, downforce and hp required vs. speed and wing angle- from these and the type of event you're running, you can make real choices.

Dave
Gen III #17