Shelby 427 Cobra

My current Cobra is:

A Contemporary kit with a real Ford 427 side-oiler (lightly bored and stroked), dual 4bbls, and top loader.  This car is blue with no stripe.  It looks very authentic, more so than the first Cobra I owned, and it's better made.  After having tasted one cobra that was "almost right", I really went out of my way to be sure this car was perfect. I wanted a driver's car more so than a cosmetic garage queen. Nothing will keep a car parked like having it be unreliable or twitchy to drive.

The first Cobra had a humongous engine, but no suspension. It was only good for drag racing, and I wanted a car that would handle like the real racers. This car has huge Willwood ventilated disc brakes on all four corners and Carrera coil-over shocks. Rear-end is a Jaguar XKE that has been expertly set up. There is just no comparison in the handling of the two cars. This latest car is tight, but has a wonderful light feeling so you don't feel like you have to muscle it around, very much like a Ferrari.

I've never driven either Cobra much, but I've always regretted time spent without a Cobra in my inventory.  These are machines designed to scare you silly, plain and simple.  The Cobras get more attention than any other car I've ever owned by a wide margin. The kit cars are very inexpensive, and they offer basically the same thrill as a $350K original for about $40K.  

What a country!

Cobra Viper Comparison

A rare opportunity to compare...

Very similar in size...

The Cobra looks better to my eye...

Another issue with a lot of kit Cobras is reliability and workmanship. After all, these cars are built by individuals in their homes, and represent probably the only car the owner will have ever built. There was some pretty funky stuff going on with my original car, and I wanted a car more like a production original that was built with fine craftsmanship. This blue car is nearly perfect. The original builder had a garage full of musclecars, about half under restoration, and half already gleaming like new. This guy really knows cars and how to make them perfect. Just to make sure the car was really sweet, I dropped it with Ferrari of Los Gatos for over a year. Their lead mechanic has worked on customers' real Cobra race cars for years and years and knows what it takes to make one of these cars right.

We did the following to make it "better":

   Changed rearend ratio to 4.11 "digger" gears. I've always gotten tons of mileage out of rearend changes--do that before expensive engine mods. It really wakes up a car. Given that the differential is an XKE with inboard disk brakes, its critical to have someone set it up right and not just your every day muscle car mechanic. This one is right!

   Replaced tires. Doesn't take anything exotic, just cheap soft compound work great. In fact, the cars don't look right if you stick modern low profile tires on them. These are the closest thing to race slicks that you see on the roads.

   Rebuild carbs. This was key to driveability. The car has twin 600cfm vacuum secondary 4-bbls. When set up right, they are the best compromise between driveability and the cosmetics of a dual quad setup. Highly recommended.

Set up suspension like the race cars, bleed and balance brakes properly. The second big key to driveability is having a suspension that's "right" on these little cars.

Set up the Cobra's funky reverse shifter so it was properly adjusted for smooth shifting.

Doesn't seem like a lot of work for a year, right? I agree, but lots of little things got fixed in addition. The car just feels a lot more "right" and a lot tighter than any Cobra I've driven, and I've driven a bunch of them! It makes it a real pleasure to tool around in. There is nothing quite like one of these retro-machines to make you forget your troubles and focus on driving! This thing corners and stops extremely well, and goes like a banshee. It feels like the fastest car I have ever owned, although I'd bet that a stopwatch would show my Porsche Turbo S to be a tad quicker. That's a $165K car, so you'd think it oughta have some kind of advantage!

My Cobra has a fine patina of wear on it that I debate about. On the one hand, I could polish everything to a fine gleam and make a show car of it. On the other hand, the patina makes it look a lot more authentic. This car is already set up very faithfully to the originals, and I kind of like it that way. The racers at Monterey are some of the finest specimens of their kind, but they don't gleam like showcars. They have a particular purpose in life and aesthetics are secondary to that purpose. I'll probably leave the patina in place.

Starting a Cobra (or other high performance carbuereted engine)

Both Cobras I've owned have been equipped with dual 4-barrel carbs. They'd probably run better and get finer throttle response with a single 4-barrel, but the duals just look so trick! These days, a lot of people have lost the knack of starting an over-carbuereted internal combustion engine, particularly one that isn't driven every day. Modern fuel injection has a lot of advantages, but one of the best is super easy starting. It isn't so hard:

  • Crank the engine until you're sure you've got gas. My Cobra has a handy fuel pressure guage, which helps. You should smell a little bit of gas close to the air filter. Be sure to give the starter and battery a break from continuous cranking now and again--the copper really heats up with the current needed for this operation. I don't crank continuously for more than 3-5 seconds with a 3-5 second rest between. DO NOT POUNCE ON THE ACCELERATOR YET--LEAVE IT ALONE!
  • Depress the accelerator to the floor once and release. Crank it again. It should pop and try to catch. If it does, try to catch it by GINGERLY feathering the throttle. If you miss, crank some more to make sure there are no pops, let it rest, and give it another single pump on the accelerator.
  • Repeat until the engine catches and runs.

The deal is that energetic pumping on the accelerator will almost always flood the engine and drench the plugs in gasoline. You can unflood the engine by cranking. It'll go quicker if you remove the air cleaner lid. Or you can just wait about the length of time it takes to drink a Starbucks (been there, done that!).

Someday, I'd love to put a fuel injection system on this car that looks like Webers. They are very cool, and would tremendously improve the driveability.

The Weber-bodied injection would look about like this, but these actually are Webers...

My first Cobra was a:

Shelby 427 Cobra.  Red w/ white racing stripe.  This was a Contemporary kit, with a real 427 side oiler, dual carbs, and 4-speed top loader.  The car had Dove aluminum heads, and was quite a handful. I remember the day I had to have it. I buddy of mine who normally buys different corvettes every 12 months showed up with it at a party I was giving. One 0-100-0 ride was all it took before I had to have it. I knew he'd get tired of it like every other sportscar he's ever owned, or at least he'd want to get back to his Vettes, so I bided my time.

The motor was really built, and truthfully was too much for the street. It had 11.5:1 compression, for starters. One time I got gas at the wrong place and they put gasahol in the car. Next thing I know, I had burned a groove between two cylinders and it was making a horrendous noise. Seems carbureutors won't meter gasahol the same as gas, and I got a too-lean mixture. Fortunately, aluminum heads are easy to fix and I was back on the road $400 later. The dual 4-bbls were also a bit much. These were 800-cfm Holley double-pumpers, and were definitely overkill. You'd stab the throttle and get 1.5 seconds of stumble followed by the fist of God smiting you in the small of the back as the car started accelerating.

While I'm on the list of nits for the car it had a funky looking big square roll hoop protecting both seats. I'm sure its safer than the standard Cobra roll hoop, but it sure didn't look right. The car also had a Mustang II suspension and kinda handled like it. There was some road rash under the front lip of the car because my pal got on the loud pedal in a curve one day and managed to drive off the road into the weeds. You've gotta keep your eye on a Cobra all the time or they bite!

Eventually I sold the car to make room for a Ferrari Boxer Spyder (that's another story), and I'm told an accountant in Monterrey currently enjoys the car as his pride and joy. Somewhere around here I have a picture of the car with me standing next to it that's been autographed by Carol Shelby. I need to get that scanned and up here I guess.

My little Cobra Blog: Random Notes to Myself

10/24/04: Got car back on the road after re-fabricating a nicer clutch linkage. It's probably been 9 months and I had forgotten how crazy these cars are to drive. You're totally exposed to the elements, the sounds and smells are glorious American Internal Combustion, and the thing is just crazy fast. I got back a bit rubber knee'd, I must admit. Need to adjust the clutch a bit more too to reduce the free play. This thing will build up the ole leg muscles even with a Centerforce clutch!

All material 2001-2006, Robert W. Warfield.