What's It Like to Drive 600hp?

[W. MITTY]

I've had a fair number of high performance cars in my life, but never anything even close to a 2400 lb. car with over 600 hp. (By the way, that's a power-to-weight ratio of almost THREE TIMES that of the C5 Corvette I owned.) I've heard lots of tall tales about busting the tires loose in any gear at any speed. For the rare few who have experienced driving a high hp/lightweight car, how would you describe it to those of us who have not? Just trying to prepare myself for the mighty Kirkham that I have on order

[MidOHasp]

No idea.

But w/ over 500HP, the tales are a little tall. Not too tall though. First gear is a complete joke, second pretty much is too although can be finessed. Third you can definitely get sideways if you are stabbing at the pedals, but if you roll on, with 295mm rear tires, 3rd is pretty steady. Fourth gear is a really strong pull up to about 120-125 (never can tell w/ the speedo bouncing between 110 and 130) and I haven't been much past 130 yet (only have 500 miles on her). That whole fun process takes around 11-12 seconds.

The whole experience kinda depends too on how you get there. I have a stroker and with the torque it makes and how long the throttle pedal travel is, I can literally have it bouncing off the rev limiter before my foot hits the firewall. That's no tall tale.

I'd imagine 600 HP would pretty much be all that but a little hairier yet.

I'd like to drive 600 HP sometime - but I'm guessing it's not much different until 3rd gear unless you have drag radials or real slicks. Beyond that though, who knows...

[Chuck Nickloy]

I may get chastised a bit here but I'll try this one.

First, the great majority of the folks that have one of these fantastic cars do not have over 600 HP. If the stats were taken, the better part of the whole would have 350 to 450 maybe 475.

Most will admit what they have is a hand full, because these cars are a hand full!

If you really want to get ready, consider a driving school. I am, and recomend it for all our customers. There is a great one close to you.

I lost control of one of these cars at 120 mph plus. I consider myself lucky as all get out to not have had a really bad incident! It happened instantly. Donuts on a drag strip with concrete both sides and a friend next to me. Again, lucky! The car has roughly 565hp.

This was in a controled environment.

If you don't prepare, you won't be prepared. For warned is for armed.

You have purchased one of the finest car out there. It will still go Sideways in a nano second.

Be ready or veg-o-matic

The Best of Times
Chuck

[MAXVELO]

I cant say anything about 600hp but I can say you'll never get the adrenaline rush from any "stock" Corvette that you will from a slightly modified Cobra! It apeals to "ALL" the senses!!! I agree with Chuck on the school! No matter how good a driver you think you are, these cars can humble the best of em!

[BlueRooster]

600 at the flywheel or the rear wheel?

[750hp]

Originally posted by BlueRooster


600 at the flywheel or the rear wheel?

I'd say that you'd be hard-pressed to tell the difference between the two.

In hindsight, I would probably like to lose a couple of hundred HP and have a high revving, high compression, non-supercharged motor. Something along the lines of a barely tamed World of Outlws Sprintcar motor

I'm having recurring dreams about a J-model Kirkham hybrid with a 12.5:1 comp avgas sucking, 398 cube dry-sumped 8000rpm small block with kinsler magnesium injection controlled via a Motec, roll-over mounted G Force staight cut transmission, and my name on the registration slip.

Anyone got a cigarette?!?!?

[Johan]

This horsepower stuff just kills me. 750 hp (the previous poster) knows what he is doing,and has been doing it a long time, but not everyone can handle that much power in such a light car.
Bill Elliott has a Cobra replica (actually a couple ) in his hanger ( I 'm pretty sure one of them belongs to the wrestler Goldberg),and for engines they have Earnie Elliott 358's and jericos for transmissions. Bill took a friend of mine up and down the runway in it and ATE a set of tires in 5 minutes. I declined when it was my turn for a ride, and Bill said "thank Gawd, that thing scares me, 4th is no better than 3rd".
The thing has sat there for three years now with two flat rear tires. I think it is around 780 hp.
The car will really only transmit a certain amount of horsepower to the rear wheels in a tractable fashion, and beyond that point horsepower is not your friend.
I removed my 13.5 to 1 pistons and changed my cam to make my car more street drivable and allow the use of less octane, and have the added benefit of a more durable, longer lasting engine. Cup car motors last a matter of hours between rebuilds, not miles or years.
My opinion is to plop in a nice durable high revving engine of your choice and don't get caught up in the horsepower wars.
500 is a LOT,
It is sort of like breasts, more than a handful is a waste.
A few comparisons:
A Military Humvee has to tote 34.66 lbs per 1 horsepower
Porsche RSR 4.95 lbs /horse
gt40 mkI 4.94 lbs/horse
500 hp Cobra (3200#s) 6.4 lbs /horse
600 hp Cobra 5.3 lbs. / horse
700 hp Cobra 4.57 lbs/ horse
800 hp Cobra 4.0 lbs / horse
Lola Can Am (1575 lbs., 610 horse) 2.58 lbs. / horse
Porsche 917 Can Am (1450 hp, 1650 lbs) 1.14 lbs / horse.

The rear and mid engine cars take the horsepower great because of weight transfer during accelleration. The Cobra does not have any weight back there, except the gas tank, which on some cars was 42 gallons.

I'm not attempting to cut down the guys with high horsepower cars, because they might dragrace them, or be engine gurus, or know what they are doing. I'm just saying be careful.

[RACER X #99]

Another BIG mistake with Cobras is barley stoppable brakes. Except for the 17" wheel crowd with giant rotors and big calipers, most of the 15" wheeled cars have brakes much too small for 600 HP cars.
For those that Open Track, you have seen the Vettes, Porshes, and other late model cars go past you just before you enter a corner. Not because they are faster than you are but because thay can drive in deeper and still slow down faster than you can.

For those that only cruise or do car shows 600 HP is 300 more than you need. You still have a better power to weight than most other cars.

And like others have said, Drivng schools,Driving schools.

Cranky

[Menace]

As more and more cobras are being built many with insane horsepower We collectively will soon not be able to insure and register/license as accidents will surely follow.. the freedom of owning these cars will be gone caused by a few...

[anchor2]

I’ve had my Cobra (500hp) for about a year. I have owned a lot of high performance cars but I have to admit the first few weeks I was a bit cautious (cautious – I would never admit afraid) of it. How quickly this car can get out of control is really amazing. I went to a driving school and spent some time on a open track and really opened it up. Made some mistakes including spinning out at about 60-70 mph but I also learned how to handle a 90-inch wheelbase a lot better.

By going to a driving school in a controlled environment you will learn what these cars are capable of. Otherwise the temptation to do something on the street is going to be overwhelming and may get you hurt or worst.

[W. MITTY]

Points well taken. I am certainly not interested in horsepower for the sake of bragging rights, and I don't want to sacrifice the longevity of my engine for outrageous horsepower. However, the alumunium Shelby engine package I'm looking at has apparantly dynoed in excess of 600 hp (crank, of course). Compression is in the 10's, so it runs on pump gas.

Am I hearing some of you right -- that 600 hp is unusable? If so, what is the practical limit for backroad/canyon/street driving? Never thought I'd be looking for ways to REDUCE horsepower

[coyled]

Whats it like? Like taking drugs(see road america video in race talk). At 660hp, the motor never stops pulling. Under 50 mph and traction is always a problem. Any cobra with 300 hp or more can run out of driver in a heartbeat. Scott

[djseed]

I only have 525 HP in my 501 (smaller hyraulic roller cam and a dual plane), but it does have 600 Ft Lbs of torque. I spend most of my time between 2K and 4.5K Lots of tractable power for accelerating and cruising. In an SPF with a Tremec and 3.73 gears, you are only doing 2K or so at 60 Mph. If you have a big cam etc, you will need to run faster to pick up the speed or your engine will lug. I guess you could downshift to 4th and run at 3K. Mine runs like a champ from 1.2K until it starts falling off at 6K. My design goal was a reliable sports rod and not a dragster. I got what I ordered.

[scottj]

W. MITTY ,
600+ HP in a Cobra is not what I would consider a “Plug n Play” device, at least not when it’s used for the track or other “spirited “ cornering.

Initially, on the throttle off corners, my car moved around a lot and was unpredictable. The solution was to either not push the car (some would refer to this as driving smart) or to fix the problems (my definition of driving smart).

The solution(s) to being able to use the power was much more than a matter of bolting on big sticky tires. I have Vette suspension so working with Dick Guldstrand and Doug Rippie, I made extensive modifications to the suspension. All pieces, such as trailing arms, toe rods, camber rods, and sway bar links were replaced with rod ends, swedged tubes and billet mounting hardware(which I believe the Kirkham alreadt has). Components and mounting locations in the rear were modified to change the camber gain and bumpsteer and all rubber bushings, front and rear were replaced with bearings or nylon. Additionally, spring rates, dampers, alignment setting and weight distribution are geared more towards acceleration off corners than ultimate skid pad grip. As Guldstrand put it, “power becomes more of a problem than a benefit when you can’t hook it up". He encouraged me to think “outside the box” when setting it up.

The point is, if you take the time to set it up, the power can be used and it will be an absolute BLAST!
Scott

[Carroll DeWeese]

Go to driving school and get experience with high performance cars. Treat the car with respect. It is a wild animal that can bite at any time. You do not have to use all the horsepower all the time. Learn to control the throttle. My car with over 500 hp is very throttle responsive. Be aware of other drivers and their ability to act and react. When I am driving on the street I leave losts of distance between myself and the car in front of me -- if you do not want a car up your tail, you can only stop as fast at that SUV with small brakes and an inattentive driver following too closely behind can stop. Learn the limits of you car throught taking small steps. As you get comfortable at a given level of driving you can "edge" up a little and get comfortable at th new level. If a problem starts to develop, you can cut back. Make transitions smoothly. Sudden braking, sudden acceleration, sudden steering, etc. are all formulas for trouble. Smooth is fast and safe. Given time, you will grow into your car. It will become an extention of yourself. Have fun.

[Johan]

Your engine will be fine, just adjust the linkage so that the throttle does not open al the way. Change it as you get used to the car of if you go to a track. There is nothing in the world to make your car seem slower than taking it to a race track.

[Ant]

Not being an expert, but having driven a variety of fast cars on circuits here in NZ, I remember going out in my first race with about 100bhp in a Ford Anglia on slicks, in those days 1970's we had cars like the PDL Mustang (banned in Aussie, and not allowed to race in the US) , this car was ahead of its time cleaned up, when you get this yellow streak and about 20 fast V8 sports sedans going past at the end of the straight and your little Anglia physically gets pushed off the track, with the wind pressure and me hitting the edge of track, as I was on pole, being slowest, one learns about horsepower and racing quickly.

Most of the people in CC who say that 300 and whatever horsepower is enough, they are right for a lot of people who have just got interested in these cars, a lot of guys haven't done any driving on the track in competitions, driving 600hp on slicks took me some time to get the momentum up and start to produce some good lap times, having said that now I am a bit to agressive in my old age and make every lap count.

I would think if your car has a good chassis, tires and is setup properly somewhere between 400 - 500bhp is fine in a lightweight car, and then that depends on what size engine, a smallblock is more driveable, and if you have a BB then you get that sheer grunt, these cars can be driven with the tail out if they are setup, but I found with BB 600+hp I would bascially show off and give it the gas a bit early and start going from one side of the track to the other, and my heart would beat a bit faster. Tires are a big issue, get good tires and they will transform your car, most street or performance radials are wanting!
A lot of exotic road cars with 550+hp etc are either 4WD or rear engined and do put the power down extremely well! In a 2wd Cobra this task is a lot more difficult.
Thats my $10 worth and I still get a big buzz out of these machines, when I get this one going I will probably make a Joe hunt of myself!!

[speed220mph]

Learn how to "roll" into the throttle, especially when exiting turns. And if your car has a locker or limited-slip diff, be prepared for the car to snap sideways--back end to come out fast--if the tires break loose. Just go at it easy and be prepared to lift off the throttle.

[BB427]

I have driven a 1050HP drag car. I ave driven a 600 HP Cobra and I now have a 475 HP Cobra. The 475 HP Cobra is , by far, the most enjoyable of all. It starts easy,it runs cool,it idles at 800 rpm, low maint., and will run on any fuel you give it. Too many people turn their Cobras into a once or twice a year vehicle. BS......Not for me.
If you want to race, build BIG HP. If you want to drive and have FUN ....use your head.
Brent

[Wayne Maybury]

As 220MPH said, learn how to apply the throttle. Stabbing it will result in problems and use up the rear tires quite quickly. Getting into it in a controlled fashion is much better but takes some practice. Also make sure that you have the correct chip in the rev limiter since you will not believe how quickly you will be relying on it.

Wayne