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I would have loved to be there with you and the team. I traded my 2012 tundra in on a 2019 VW Tiguan. It can only tow 1500 lbs. I wish you and the team all the best, and even more prayers and love to your wife.
On a flat tow, the straight pull on this car is about 400 pounds. No problem! Come on down! In 2012 Steve brought one of his kids Quads and that pulled it around in the pits. Was a little much for the little Quad, but it worked. Your SUV would have no problem.
Last edited by Carl Fausett; 07-15-2019 at 06:39 PM.
Today we put up the belly pans with their ballast. The driver's side weighs about 500 lbs and the passenger side weighs about 650 lbs. Definitely a two-person job! From the side, they will be adjusted so they are higher at the rear than at the front - creating a low-pressure area as the air flow gets to the back of the car to generate some ground-effect downforce. I remember describing how the car would get real squirrely up through 160 MPH, then it would suddenly settle down and squat a bit and get much more civil. He confirmed how much lift he saw in the back of the car up to 165 MPH in the wind tunnel, but that was where the ground-effects started to work and pulled the car down enough to negate the previous lift. Since then, we have made changes to greatly reduce the left we were getting.
The rear diffuser carries the air flow right afterward these belly pans, and they will be installed soon also. Tomorrow I should be hanging the side skirts and setting the ride height. Initial ride height will be 1.5" off the ground, and may be adjusted up or down depending on track conditions when I get there.
A rare pic of the belly pans with just one side in place, so you can see the difference Here both sides, totaling 1150 pounds, are up. You can see the channel down the center they form for the exhaust and Torque Tube. Belly pan from the side. This will be adjusted to be higher at the back than the front before the side skirts go on.
Got side skirts to seal the airflow there next to the ballast pans? Aero under the car from simple stuff like the sloped plate only starts when you can keep air from coming into the side of your cavities. More active aero under the car has ducts that start in the front and exit in the diffusers under the rear bumpers. The vertical strakes in the diffuser are a requirement, and the aero ducts are sealed all the way to the ground on the sides. You would see that in the wind tunnel with traces strings or ribbons at the bottoms of the rocker sills. The wind tunnel results are distorted if the floor isn't moving.
The airflow management under the car, and especially the rear diffuser, isn't something that worth guessing at. It will cause more problems than gains if it isn't done really well. If you start depending on the under-car aero for rear downforce, you'll get a brown-patch surprise if you get at all sideways or see a stiff enough crosswind to disturb the side seal with the ground.
Pics of the rear diffuser are posted above at post #9 above. Here are the side skirts on the car from 2011. There is even skirting behind the front tire - all that we could do to prevent the incursion of air from under the vehicle.
Here is a picture showing how the side skirts carry around and behind the front tires.
Last edited by Carl Fausett; 07-18-2019 at 08:16 PM.
Here is Myles and I installing our lead-filled tube into place over and slightly behind the rear axle. Each one is about 150 lbs, so 600 pounds in total. The engine hoist allows us to lift two of them at a time and place them (carefully) over the fuel cell and bolt them down. Now that all the ballast is in, I will set the ride height. Coming soon: the alignment, the side skirts, and the front air dam. We leave on August 8th.
These pictures show the final ride height as-raced. At about 100 MPH, the car will be settled down onto the suspensions stops and another 3/8" of what you see here will be gone.
Surprised you’re not using AirTabs on your rear....
I’m quite interested in your diffuser, would like one for mine but have to work around the wheelie bars.
Will be doing the “**** wing” on the rear, as mine will be under 160 mph top end. I need downforce with little drag.
Probably get your splitter for the front to keep the nose down.
I used air tabs before and it made the rear wing more effective, and increased my top speed enough that I could measure it on the straight from corner 14 to corner 1 at Road America. This time, however, going with a different package and a vortex generator mounted much further back. I like the air tabs. I put them on the aft edge of my trailer and I gained 2 MPG with my Chevy Suburban when I was towing.
I used air tabs before and it made the rear wing more effective, and increased my top speed enough that I could measure it on the straight from corner 14 to corner 1 at Road America. This time, however, going with a different package and a vortex generator mounted much further back. I like the air tabs. I put them on the aft edge of my trailer and I gained 2 MPG with my Chevy Suburban when I was towing.
Yup yup, I’ll be installing another set at the “top of hatch” roofline as well. Great product.
Finished putting the belly pans up. First pic shows all the pans as seen from the front of the car, second pic is a close-up of just the engine belly pan. A tad heavier and larger than the stock engine belly pan!
Pic shows all three sections of the bottom/belly pans Close-up of the engine belly pan.
We got a service vehicle for Bonneville - a previous 928 owner who lives in Salt Lake City heard our call for a tow and service vehicle for use at Speed Week and has generously agreed to let us use his Toyota FJ. Whew! So glad I don't have to drive another vehicle from here just for that. Many thanks, Kyle!
Rebuilt calipers are installed and system bled with fresh fluid. Now the alignment... take out the road racing alignment and put in one better suited for land speed racing.
07-15-2019, 03:57 PM
