Carl Fausett

Video is up:

My shift light is set at 6800 rpm, Brian waves me off at 7000.

http://www.youtube.com/watch?v=GF1Ik...el_video_title

hacker-pschorr

Is that an elevated or in ground dyno?

The #1 problem we have running full load extended runs is heat on areas that are normally seeing 100+mph airflow at those power levels.

The superflow we use in Neenah is elevated which gives the room for a ton of fans under the car blowing over the exhaust, oil pan etc... Sure this doesn't simulate 100+mph winds, it's better than nothing:
http://mpi-ferrari.com/

Then you have this place in Mosinee - I've never been there, it looks like they have quite the fan system infront of the dyno.
http://www.doneriteautomotive.com/

Carl Fausett

It's elevated and they too have excellent air movement. I have also gone to a dual-pass radiator on this car and that has made a big difference.

Actually, this engine is running cooler than the 5.1L supercharged motor I ran for the last 4 years.

ubercooper

Awesome job Carl, 900hp is going to spin the bejesus out of those skinny tires, especially on salt.

What top speed are you guys aiming for / whats your gearing like?

...looks like its time for me to get a blower and some nitrous

Iwanna928

Ubercooper I like the way you think!

Carl Fausett

The world record in BGMS (Blown Gas Modified Sports) cars is currently 231.5 mph.

Our math tells us that, with a Cd of .34 (stock Porsche 928), with the frontal area of a 928, and with the gearing and tire diameter I have; that we need 750 HP at the tire just to tie the record.

Now that I have 765 at the tire, the rest we will get from improvements in aero - maximising those adjustments the rules will allow in reducing drag and frontal area. We are not allowed to modify anything behind the cowl. The rear wing is made to rule book spec and offers no advantage - it is just meant to reduce the number of blow-overs they see at Bonneville.

Carl Fausett

Video of a typical blow-over.

The term "blow-over" is borrowed from hydroplane racing....

http://www.youtube.com/watch?v=Kq-C9...eature=related

rgs944

Exciting stuff Carl. Great work.

Gregg K

That is so cool. Your tow vehicle isn't too shabby either. I really hope it goes well.


And to think you could have just bought a Veyron.

andy-gts

in that video above , were the rear wheels spinning too fast on the salt and caused the spin out?

Carl Fausett

I can only speculate, but usually the nose is loaded with aero and downforce, the load on the rear wheels gets lighter; and the nose plows into the wall of air (which gets harder and harder to penetrate) and the *** end tries to come around and pass the front end....

The car, equipped with side skirts and air dams, will do well to keep air from going under the car so long as it stays down. Once the car rocks a tad and air is allowed to get underneath it, the car becomes a wing and takeoff occurs.

jorj7

Very impressive numbers Carl. Looks like you've got a monster there.

Bill and I plan to be at the Silver State Challenge ORR Sept 15-18th, so we'll
be down the road in Ely. Don't know if we'll have time to swing by, but
we'll see.

anonymousagain

Very nice Carl !!

Curious about the 231.5mph mark.

Considering that Mark, Tim, Cheryl and a few others have passed the 200+ mark during ORR, with substantially fewer modifications and HP, is really a testament to how much more effort is required to squeeze that little bit more mph out of Physics.

Look forward to seeing 232 on the side of the car afterward!!

Carl Fausett

Correct. Air resistance is exponential, not linear. What is it that Bugatti said about the Veyron? It takes them 250 HP to get the first 150 MPH, and 700 HP to get the next 100 MPH. Something like that.

Gregg K

Air resistance force is a cubic function of speed, if I recall.