how fast are the Daytona Coupes?

[427sharpe]

Cal, you are spot on as usual.....all the 65-66 GT350's came with "K" 289's given an intake, cam, carb and headers to boost to 306 gross hp. Legend has it that when they were in a meeting to come up with the name there was a lot of bickering going on, and it po'd Shelby. He asked Chuck Cantwell (GT350 project manager) how far it was from the production line to the race shop. Chuck said 'about 350 feet' so that is how Shelby named it. It had nothing to do with hp or torque or displacement, ever. The GT500 was named because it 'sounded right'!
As for 200 in a Daytona? I'll believe it when I see it! I really believe that 180-185 is about the limit for any Daytona other than a ringer. As for 'better aerodynamics than a GT40?'

[Excaliber]

I personally DO believe Dick ran 198 mph with his COBRA as clocked and recorded at the time. That with a big block of course. It is not "that much" of a stretch for me to believe a Coupe could do 200 mph, even with the small block.

Coupe better "aero" than the GT-40? Depends on what you mean by "better"! I wouldn't be surprised if the Coupe did indeed feel more stable at high speed. Drag coeffecient? Thats another debate!

No doubt the GT-40 had the benefit of wind tunnel testing. The Coupe design certainly didn't. Remarkable to say the least!

Ernie

[bwana50]

Don't know what the drag is for a Coupe, but according to the Nov 2003 Car and Driver article about the "new" GT-40, the "old" GT-40 had a c/d of "about .43". Not as aerodynamic as it appears.

[Hal Copple]

when Bob Olthoff showed me some pics of one of the prototypes he was running in SA this spring, before things were pretty well finalized for production, he had one of a shot of the Coupe's speedo, reading between 185 and 190 mph, Bob said he was running up on some traffic, and had to brake, but the car was still accelerating.

The suggested engine is a 402 Roush, if you get a Coupe from the Olthoffs, presently they are carburated. A big block will not fit between the frame rails. The Coupe is more spectactular under the body, with all the race grade stuff they have under the body, which at present is not available in Kevlar, as they have not been satisfied with the finish they can do to SPF standards on the Kevlar. Hard to get the "print thru" to be completely invisible.

Some very careful computer analylsis suggest a top speed of 219, but very few cars out there can do this, i have my own hunch that it will do 205-207 mph. Bob has told me his race Wilmet coupe, a little different than the Shelby Daytonas, would go about 198 mph, (for the unaware, he raced it and Cobra roadsters a lot back in the '60's), so with a hundred-plus more hp, this one should do a bit more than that.

One of these days, we will find out.

It is a truly stunning car. I have ridden in it, and it combines refinement with staggering performance.

[Excaliber]

WOW,,,, .43 for the GT-40 is a "drag"! I would guessed it would be in the low .30's based on "looks". Thats the thing about CD, it's just really hard to measure without the right equipement. And "looks" can truly be deceiving!

Of course many race cars use various "aero" functions to put down force on the car. This causes the CD number to go up by increasing "drag" but the car STAYS on the track! You got to find the right balance between speed and staying on the ground! "Loose" is fast, but the "risk" goes up!

Running the "flats"? We don't need no stinkin' wings or spoilers to slow us down!

Ernie

[California]

DRIVE TRAIN: The Coupe is designed to take a Ford 351 Windsor engine that can be stroked to 427 cu in. The chassis was engineered for a six speed Tremac T56 transmission. The Coupe is fitted with a 3.46:1 BTR Hydratrack differential, arguably the most modern slip-controlled differential available for road cars today. Roush Technologies developed the Roush 402 RC engine for the Beta and Gamma prototypes (the Alpha prototype competed in the 2000 One Lap of America with an Olthoff-developed engine). The RC develops 501 bhp at 5,900 rpm and 580 ft/lbs of torque at 4,900 rpm, giving the prototype amazing performance figures: 0-60 mph in 3.8 seconds, the standing quarter mile in 11.5 sec and a top speed in excess of 200 mph.

This car is the best thing since chocolate pudding and you know what else(hint meow)!

Nick

[Bruce Robles]

Hey Cal and 427
I remember hearing that story about the building being 350 ft. away now that you mention it, however I was refereing to the rated horsepower of the Competetion Engines not street engines. The GT-350 race cars or 'R' cars as they have become known as, were raced with a 715cfm Holley carb on an Aluminum Hi-Rise Manifold. The advertised rated power of that engine was 350 hp with race heads, matched intake manifold and race cam and headers. And you could buy them complete from Shelby for racing.
The GT-350 street models utilized the 715 cfm Holley carb. and the Hi-rise mainfold with the TRI-Y tubular headers as did the 'R' cars but all bolted to the 271 HP 289 Hi Po. or 'K' code engine and developed and advertised increase of 35HP over the stock Hi Po. 289 to 306 Hp. The 289 Cobras came stock with HiPo 289 with the Ford cast iron intake minifold and an Autolite Carb., although there was a 2 4 barrel AFB's Manifold, (DRAGONSNAKE) and a Weber set up as options, and other's they would gladly bolt on for you at Hi Performance Motors for an extra charge of course! Some 289's sold new and used in '65 at Hi Performance Motors could get the 715 Holley Hi-rise as an option.

By the way, are there any purist out there interested in a pair of CORRECT &ORIGINAL Iron Race Heads from Valley Head for thier vintage racer? They are unassemebled and have been in storage since 1970 when they had one SCCA National Race weekend on them after purchased new.

Remember "Too much is just right".

[Mike Stenhouse]

The following is taken from a soon to be published article that I am writing on the new Superformance Coupe.

"In a final competitive hurrah, the original coupe CSX 2287 was taken to Bonneville in November 1965 for a series of land speed record runs. Configured just as it had completed its racing career and with no special preparation, it set a Class G record at 187 mph and set a total of 23 USAC/FIA world speed and distance records."

"The striking shape of the Daytona Coupe was never tested in a wind tunnel and its drag coefficient - the measure of aerodynamic efficiency - never determined. But the Bonneville run gives us the most accurate measure of the top speed of a particular car and engine under known atmospheric and altitude conditions. From this data and some rather complex mathematics, I calculate the drag coefficient to be 0.29. Wow! This is as good as modern automotive designers have been able to do for the most aerodynamic of modern cars with computer aided design, wind tunnels, huge budgets, and a strong directive to reduce drag and improve fuel economy."

There are many legends and rumors about the top speed of the Daytona Coupe. I discussed these at length with Peter Brock and we felt the Bonneville runs were the most accurate representation of the top speed of the Daytona Coupe. The runs were made with the car just asit came off the track at the last race. In racing trim, the 289 with Webers made 375 to 385 horsepower. There were claims of 198 mph at Le Mans, but the track was wet and wheelspin was most likely a factor.

In case you are wondering how I did the math, you may recall from my last post that I am a rocket scientist with a BS and MS in Aerospace Engineering and a PhD in Mechanical Engineering.

Hope this is helpful.

[Mike Stenhouse]

The GT-40 was not designed in a wind tunnel. When it finally made it to a wind tunnel, they found that the complex "airflow managment systems" i.e. scoops and ductwork, consumed more than 100 horsepower. The drag coefficient of 0.43 would not suprize me.

Based on Ford's claimed top speed of 195 mph for their new Ford GT, the drag coefficient works out to be around 0.38.

Due to improvements in design, the Superformance Coupe will prove to be more aerodynamic than the the very sleek Daytona Coupe, which is substantially better than the Ford GT. The Superformance Coupe has about the same frontal area as the Ford GT and about the same horsepower. With the lower drag coefficient, it should be at least 10 mph faster. And that would be 205+ mph.

But this is just bench racing - words and math. Someday somebody will prove it and I hope they report it here.

[Bruce Robles]

At LaMans in Ford's first attempt with the GT 40's in 1964, I think Richie Ginther or Chris Amon went 203 in practice for the race. Both cars were running the Coletti gear box and skinny Dunlop tires. They broke the gear box's and both DNFed. These cars had very pointed nose's on them which caused the front to lift at high speed. Not the nose's Shelby made when they took over the program from the Brits. These changes were first seen at the 1965 Daytona 24hr. race, they finished 1 & 3, as I remember. They added chin spoilers down low in front of the tires, and changed the radiator intake. The noses were further developed by extending them a bit, they lost the chin spoilers completely, and changed the radiator intake to what you see now. All the teams had thier own tweaks so there are some variables of coarse.

The MII's had huge air intakes behind the doors and some scoops that stuck up on the rear deck lid. They also had some tabs added on the sides of the nose that went on an angle over the top of the front wheel wells. Shelby's team and Holman-Moody's all had different little tweaks that were within the rules.

The MK IV was really designed with drag in mind and much slicker than the others.

[Excaliber]

Now I'm no rocket scientist...........

But Mike IS!

Ernie

[SPF604]

Well I may never go 200+ in the new Superformance Brock Coupe, but Bob Olthoff did give me a ride in the sleek red coupe the week before he went to Goodwood. And, I can report that as with most modern, high performance cars, 110 mph felt like 55 mph! It's fast, very fast and rock solid. No suprises. A photo of the Brock Coupe at the Olthoff's shop is in my folder.

[Maricopa]

Seems like I read somewhere that the Pantera (in it's original non-flared fender/giant wing etc) form has a drag # somewhere around .27

Mike

[Randall Thomas]

Ernie: is the Naval equivalent of a Rocket Scientist, a "Submarine Specialist?" We're niether, but Doc Stenhouse is one of em!

Bill A: That's what everyone is saying... that in the Superformance-Brock Coupe it feels like HALF the speed they are really going. And that is awesome in terms of high speed potenial, and fearsome if you have less than a perfect driving record ;-)

Mike, I have a Pantera GT-5 and that wing really does use the wind. My hatch opened up at about 50 and the gas shocks shot it stright up. Pulled up to a buck twenty on the speedo and it not only pushed the hatch down, but at 140 it clicked it back shut. And I'm sure the long arm would have understood had I been placed into that situation to explain that.

Doc Stenhouse, I would be interested in the aero-comparison of the GT-40 and the Pantera... while the '40 looks sleeker, the Panty does look less "busy" in the wind.
http://performanceunlimited.com/clas...s/photo18.html

Also, what specific points on the Superformance-Brock Coupe were the most improved over the vintage versions? does the car have more or less downforce, and is there a point where the downforce is "too much" thus reducing top speed potential? I really need a wind tunnel in my back yard... oh, wait, that would be called "spring" here in Tornado alley.

/Randall

[Maricopa]

LOL, great story Randall. You know, some people would have just pulled over and shut the hatch by hand.

Mike

[avanti-176]

Aerodynamics are interesting things......

It's a fact: The rear window popped out of early production Avantis if driven over 100 mph!

It's a fact: Ron Hall drove his 1963 Avanti to 200.426 m.p.h. in class DP/S at Bonneville on September 22, 1993.

It's a fact: Jim Lange drove his twin-turbo Avanti, to a record-setting 211.929 m.p.h. at Bonneville on August 22, 1996.

It's a fact: A Studebaker Avanti at Salt Lake City achieved a certified 196.62 m.p.h. in 1963.

It's a fact: Avanti was the first American production automobile to have disc brakes

It's a fact: "Indy" 500 winner Roger Ward was the World's first Avanti owner

It's a fact: The Avanti drag coefficient was 0.30 when most stock American cars were in the 0.50's

I copied these off of a Avanti site. Its funny though you would not think by looking at a GT-40 and Avanti side by side that the Avanti would have a lower drag coefficient. The same applies to the Crotch-Rocket motorcycles of today,they are not nearly as aerodynamic as they appear.

Anyway it is just me carrying the Avanti torch since they have always injustly been left out of the discussions about american cars and speed. Especially in the circles of people my age.

Everyone have a good one,
Dan

[mr0077]

Yeah, but Avanti-176,
They cheated on that 196-mph run...they bolted on a full belly pan and changed tires...NOT FAIR!
Seriously, I was in college at the time, and lusted after one. I remember drooling over the poster at the Studebaker dealer that showed that record-setting performance...almost committed a crime just for the poster! Classy cars!

[Excaliber]

I wonder what kind of tires they ran for high speed runs back in those days? I understand tire selection is one of the more difficult aspects of setting up the car (even TODAY)!

Ernie

[Cal Metal]

If that is the real drag coefficient on the original Daytona, it is just another testament to the great skill and intuition of Pete Brock. That guy deserves a lot more credit than he gets. A true genius.

[G.R.]

And some people think the coupe is ugly--like the design wasn't completed at the back--some think the thing is "butt ugly"--
Maybe they'll rethink that one, that is what they are looking at when trying to catch up with a coupe


The Brock coupe is one beautiful car IMO