mark kibort

best not to run a wing, as most do not. you dont want to lift the nose at 220mph. putting downforce on the front to match the wing is touch to do.
just keep the car straight. put on an airdam up front maybe skirts, and he should be fine. wind tunnel time is VERY expensive!

James Bailey

Quick search finds a MODEL airplane wind tunnel...."Example of a Cost Estimate:
This example cost estimate is for a customer interested in conducting a wind tunnel test of an aircraft. Electronic Pressure Scanning (EPS) data will be collected in addition to standard force and moment data. The proposed test matrix totals 300 wind-on runs (each run is a set of test points where only one parameter is varied, such as the angle of attack or sideslip.) The test matrix also calls for 100 model configuration changes. The customer wants a test report.

Installation Time: 6 hours

Actual model installation times vary quite a bit depending on model complexity and the model manufacturer’s familiarity with UWAL’s model support systems. Sometimes it’s as short as 2 hours, other times it’s 2 days. For this example, 6 hours is used as a reasonable estimate.

Total Wind-On Time with EPS: 25 hours

Assumes an average wind-on time of 5 minutes per run. Run durations primarily depend on number of test points and how much time EPS zeroes /cals add to data acquisition. Runs typically last 4-7 minutes at UWAL.

Total Model Change Time: 30 hours

Assumes model changes take 18 minutes on average. Note that some model changes may take several hours.

Model Removal: 2 hours

Total Time Required:63 hours (or 7 days at 9 hours/day)

Tunnel Rental: $26,775 (63 Occupancy hours at $425/hour)
EPS Set Up and Usage: $2,500
25 Feet of Trip Dots, including sales tax: $314.82
Test Report: $250

Total: $29,839.82 " ..............
This is the University of Washington Aero lab.......wonder how much a full sized tunnel rents for ?

Aspkiller

A couple of Bonneville guys use the dyno at our shop in Carson City. We are constantly amazed that anyone would actually get in some of these cars and drive them at speed (based on the fabrication expertise we see). So, based on the prep that Carl has done, I suspect he has a leg up already on at lease half of the field.

760 RWHP and the aero I see makes me believe 230mph is likely. Go set a record, Carl.

James Bailey

I too have seen some "Bonneville" cars at El Mirage dry lake and talk about weird, crude, make do engineering......but they seemed to be having fun ! Traction there was a big issues as well saw a couple big spins ! They had to post volunteer guards along the course to keep the windsailers and dirt bikes from crossing the "track".

928mac

Wow James I had know idea that wind tunnel time was so costly.

I never guessed that it would be that much.

Edit: maybe bigger is less because I did find a much cheeper wind tunnel

http://www.wired.com/cars/coolwheels...5-10/pl_motor#

bcdavis

Yeah, seeing how touchy aerodynamics can be, and how adding wings can slow a car down, it seems like it would be better to leave the car close to stock, just lower, and just add weight to aid traction. Seems easier to add or remove some steel weights, rather than continually messing with aerodynamics, which is a bit more tricky.

James Bailey

Granitelli years ago did some record runs and carried a bunch of water in a big tank used it as ballast and to cool the intercooler, as long as it is full it does not slosh around They could easily dump the weight when hauling the car around and add it back with a garden hose....

hacker-pschorr

I would guess in order to do proper aero testing for top speed a rolling road dyno would be necessary. So call your nearest F1 factory and see how much they want for 30 minutes

A lot of those sitting around the Salt Flats?

Imo000

One of my favorites. That guy was the ultimate DIY gearhead!

bcdavis

Then again, a lot of those salt flat guys work on their cars all year long, and only get to run them at Bonneville. If something doesn't work, they go back to the drawing board and come back next year. There aren't many places to do testing of extreme speeds and aerodynamics. That's why I was thinking it would be very useful to have some quick options to change the setup of the car, if there are problems on the first run. Like if there are traction issues, it would be better to try adding weight, than adding downforce, which will slow you down. It also might be good to bring the big wing, but if you aren't quite hitting the top speed, take off the big wing, and try the stock spoiler instead...

928mac

Hacker, who are the two in your avatar?

jorj7

One of them is the Cal Quarterback from a few of years ago, now plays for
some team that won the superbowl... Can't imagine why Hacker would
use him in an avatar.

GregBBRD

"Interesting" has a bit of sarcasm it, when used here.

Seriously.

This form of racing is not running up Pikes Peak, measuring your time with a sundial, when everyone else is using a stop watch, and then going and writing a book about it. This is serious business!

At these speeds, you can kill people when the engine or anything else fails. I'd sure not want to be anywhere near that car, if the engine fails at over 200 mph. The driver might survive....might not.

You need to get this engine onto some sort of a test apparatus where you can load it up and really test it. Blowing through a rear wheel horsepower dyno test for 20 seconds is not reality....it isn't even accurate.

Load that engine up and take it to an engine dyno and run the crap out of it. Run it at WOT for extended periods of time! Not 20 seconds...but for 20 minutes! It needs to be absolutely bullet proof! I'll even loan you my DTS adaptors, if you can find a DTS dyno.

Not knowing if the engine will live or not is irresponsible when you are going to try and go 230 mph!

IcemanG17

George blew an engine at 189mph......and slowly coasted to a stop....I do think having an automatic that prevented the sudden locking of the rear wheels when the engine seized probably saved a significant "off"

Carl Fausett

True. For a full-on amateur effort.

While we are not a full pro effort, I like to refer to us as a semi-pro racing team. We are paid by our sponsors and they do expect us to perform. I am the toughest one here on that... if I say I am going to be someplace with the car at a certain time - I mean to be there come hell or high water.

So, its a little harder for us, the world is watching ( OK, not the world, but our customers and sponsors) and we want to get it right the first time out. Thats a much higher standard than the family race team who, if they win or fail or bust it doesnt matter so much.

Announcing what we are trying to do before we go is more like Babe Ruth calling his shot. :-)