My Bonneville Project up date
I have 600rwhp in my C4 Open Road Car and the fastest I have hit is 206mph and that was about all she had.

Interesting enough this was the Dolly Varden straight about 30 miles west of Wendover at appox. the same altitude as the salt. This is also on pavement which has somewhere 25-30% less rolling resistance. I have a buddy offically radar clocked at 227mph and said he saw 232mph once again on pavement. He has 850rwhp. Now I will grant you that my wing will cost me some top speed, my buddy also has the same wing on his. Once again I am not trying to discourage you, but passing on info from some one who has been in simular shoes.
Jeff
your car sure looks like 220 standing still. wonder how much the wing is impacting top speed.
are you drag or rpm limited?
I have 600rwhp in my C4 Open Road Car and the fastest I have hit is 206mph and that was about all she had.

Interesting enough this was the Dolly Varden straight about 30 miles west of Wendover at appox. the same altitude as the salt. This is also on pavement which has somewhere 25-30% less rolling resistance. I have a buddy offically radar clocked at 227mph and said he saw 232mph once again on pavement. He has 850rwhp. Now I will grant you that my wing will cost me some top speed, my buddy also has the same wing on his. Once again I am not trying to discourage you, but passing on info from some one who has been in simular shoes.
Jeff
and that max tqr is at between 5500 -7500 rpm.. While your frontend, may be effective at road racing speeds for cooling and venting, its looks like a lot of disruption in the boundary layer. bet you would be supprized if you took it to the wind tunnel.
The spreadsheets would indicate that if your car was bone stock, with 600 rwhp, you would have beat significantly beat your 206 number So I actually believe you have way more drag than you think. or that u were making much less hp at the 4200' of elevation at wendover. Which is probably the case
if you don not have some form of boost, the straight math would say 1" of mercury for every thousand feet, so you lost 4.2 # of boost if it was only 56Degrees outside. this would equiate to about 25% of your rear wheel Hp giving you about 450 rwhp. which fits a low 200 number.
your car is 2-3 inch's higher than I will run, I will actually be triming my front spoiler to keep it 1/4" off the salt, This is big, as its all about frontal area my car will be on bump stops no suspension or movement, your car is lifting on the suspension in the front with speed. your fat tires are also adding tons of drag. you can't run tires wider than 5" on the salt, it just don't work.
we will, see I am very confident of getting over 220, and 240 if I can develop some boost with my air intake idea
Thanks for your comments. We will know the answer in less than 6 months.
Ps. if you look back at the earler posts you will see the current record holder. He did it with a nascar engine, putting out about 800 hp. My goal is to beat his number with less Hp, by working on the drag aspect. hope I am right.
Dave
Last edited by Daves obsession; Mar 14, 2009 at 12:20 AM.
Sometime during Speed Week
For people who've never been, Its a great event to witness, grassroots people doing what they love.
The Best of Corvette for Corvette Enthusiasts
Doesn't that salt create a ton of drag too. The show Top Gear had the new ZR1 out there and it didn't get anywhere near 200.
Jeffs car is an outstanding example of a open road racer, its just a whole different game, his car probably weighs 2400-2700#, with wide tires
a salt car will be 4500-6000# depending on the top speed being attempted.
the stock 1990 ZR1 was a 175 mph car with 375 hp, on the salt I would guess it might make 150.
If no changes are made to the Coefficient of drag CD , then it will take 793 flywheel hp to make 231 mph.
to beat the 230.5 record it will take, droping the CD from a .34 to a .27 and reducing the frontal area from 19.2. ( 1990 calloway turbo has a reported .26 CD)
The frontal area, is the big multiplyer, taking the mirrors off, reduces this by about .5 lowering the car 5-6", and getting a vacum under the car is good for another 1 square ft. narrow tires give you another .5 reduction.
The Key is to clean up the CD, and reduce the FA. with out modifying the body other than taking the mirrors off which is allowed.
The math says, that 450 RWHP is required to go 230 mph with a frontal area of 19.2 and a CD of .27
The real problem is the density altitude, 4200' plus any temps above 56 F. at speed week in Aug, its 46 in the morning, and 95 at 3 pm.
I am very confident of getting RWHP in the 650 range at low altitudes which is about 480 to 430 RWHP at altitude depending on temps.
So as you can see, it all comes down to being able to create, some form of boost with out creating drag. The current record holder did a great job of this look back at the pictures. I am just taking a different
approach, with my modifed NACA air intake design. which should provide 1-2 psi of boost, without increasing the CD. or FA.
Dave
Last edited by Daves obsession; Mar 14, 2009 at 10:37 AM.
I've always said I'd rather be lucky than good. It's nice to be both. It certainly appears you've done your homework. To get well over 200 mph (and back safetly) you're still going to need to be lucky so GOOD LUCK! With that said, if you reach your objective it's going to be because you're also good and it surely appears as if you are! Please keep the pictures, explanations, status and stories coming. This is GREAT READING.
you have good points. Let me add some info. The tires I use when racing are 275/19/50 tucked well inside the fenders these are not very wide,but wider then the 5 inchs that you run. The tires and rims you see in the picture are the roll around tires for pretty pictures and to protect the race tires. My HP numbers were ran in Boise, ID at 2600 ft and 85 temps. So I am losing some HP but not as much you may be thinking. There also is no front end lift on my car the white air dam at speed is against the ground. The vented hood releaves all pressure build-up. Also with the wing on the rear and vented hood at speed I am on the bump stops so I am also right on the ground. With your thoughts of getting some "boost" from an intake is a dream there is little to no gain with a ram effect. You also asked, I believe I am drag limited at 206mp I am turning 5600 rpms and the motor should be good to 65-7000. Good guess on the weight of my car 2645 lbs. My buddy that runs the salt will also be at speedweek so I might be there. If I am I will look you up to cheer you on. I have nothing but respect for people on a quest like this, I have been there and was lucky enough to have reached my goals. I waer my 200mph club shirts and jacket with much pride. When my open road friends join the 200mph Open Road Club I am as close to excited for them as they are themselves. I understand the dedication in time and money it takes to chase this type of dream.
Jeff
if you look back at the current record holder he did an excelent job. though i bet his engine was really lean at 100 mph, as his scoupe is under sized ( with a 372 cid, you need 15 sq in at 100 mph, and about 8at 200)
Later when I get my intake built I will post some pictures. The fab work is going to be done, by a guy that builds and races Red Bull type airplanes. he is well known for his air intake work. particulary Curved Naca vents used for intakes for supercharged airplanes and has access to a wind tunnel.
His and hers thanks for the kind words its been a learning experience for sure! in about two months we will have the web site up for Texas Childerns Hospital. We will be taking pleges for every mph i make over 200, so everyone can participate with me. The TCH turns no child away, and this is paid for by charitys only.
Last edited by Daves obsession; Mar 15, 2009 at 12:28 AM.
Jeffp I am still sorting out what will never go back on the car. Very quickly I will lay all the left over parts on the Hanger floor, and photograph whats left and post them. I would love to sell as a whole cause I have better things to do with my time, than ship items.
Also I may sell the AC sytem as a whole.
right now, door pannels, and sun visors are spoken for.
anything in particular u are looking for?
PS, I spent all weekend painting the Cage, dang thats a lot of surface.
Trey, new liners and a small stroker crank to take the displacement to a 372 ( top of the c class ). stage 3 cams, bumping up the compression a notch. Head porting, total rework on the plentum. Throttle body work. 3 1/2 exhaust no cats or muffs, 110 octane, and the infamous Corey tune.
Last edited by Daves obsession; Mar 18, 2009 at 09:38 AM.


















