Cobra Safety and HP

[Richard Hudgins]

OK FOLKS,

Everyone needs to read my first post. I stated:

"There is much being said about how dangerous these cars are. Well, I beg to differ. Any of the chassis's currently available can handle 10 lbs per horsepower quite well and would be quite safe in the normal drivers hands. They would also be quite fast."

What I am trying to get across to everyone is that the Cobra "per se" is not an inherently dangerous design as has been stated by others.

It only becomes dangerous when someone makes the platform unstable. And a 500+ engine does this REAL fast.

I am not against putting in crazy motors. Hell, they make them fun. But they also make the car a very unstable and dangerous beast.

My point is this. There are very few folks who can effectively deal with a power to weight ratio below 5-1 in everyday use. I know that everyone will say, "I never use full throttle, etc. etc. etc."

Guess what, it seems that a few have done just this recently and there is a post saying “Cobras, unsafe at any speed”. My point is that properly designed cobras are not unsafe at any speed. However, builders think that they need to put in an engine that makes the car virtually undriveable from an engineering standpoint. Sure, it makes much noise and can spin the wheels in any gear. All that is great fun.

But, does it make for a proper overall performance package?

I guess it really comes down to what you want. Something that works really well, or something that appears to.

Pat,

I try not to discuss my miss-spent youth. But yes, I have raced a number of cars. The ones shown are among the multitude of vehicles that I abused. The coolest part is that I got paid to do it. (That will show you how stupid race team owners are.)

[petek]

I wonder what percentage of Cobras have engines with more than 500 hp. Of those that do have more than 500 hp, I wonder how many of them are driven on the street more than once a week.

and flipping everything over...

I wonder how many Cobras out there have less than 500 hp and how often those Cobras are driven on the street.

Even with less than 500 hp, you can get yourself into some interesting situations with a little bit of pressure on the throttle of the Cobra!

[Richard Hudgins]

Bandit 1.

You stated: "I guess none of you "preacher types" have never went above the speed limit ever, not even because you were late to work or something."

I think that you are missing the point here if you think that I am a "preacher".

If you consider me a "preacher" you certainly do not know my past.

I have spent my time on this mortal coil designing, building, and driving very extreme vehicles. And having a hell of a lot of fun doing it.

But, I am also a practical engineer. My job is to produce products that work. And this means understanding the requirements of the application.

I have never seen “Fast and Furious” Hollywood fantasy and Bull**** about vehicles are outside of my reality.

Please read my posts and pay attention. I am not trying to make the Cobra a lesser vehicle. Only trying to instill some proper design theory.

[KobraKarl]

Richard,

nice post.

[BANDIT 1]

Mr. Hudgins:

My comments were towards the "judgmental a$$holes" whom are judging the recent Cobra fatality without having all of the facts. I have yet to see a newspaper article of an event like this that was even close to the "real" way things happened. For all we know the Cobra driver was minding his own buisness and the Trans Am pulled up next to him and "punched it" and lost control and crashed into the Cobra.

Where I do disagree with you is about the horsepower issue. It is totally logical for a dealership to "warn" you and see if you know what you are getting yourself in for, but please don't tell me what I can and can't handle.

[Bill E]

The system can be switched from timing turn back mode. To drooping cylinders. slip can be adjusted from 2% to 35%. the unit only droops timing 5 degrees in timing mode and you can drive through it but you will know it is there. It is grate for the accomplished driver. The dropout mode will not tack out the same cylinder twice and is for the moor heavy handed driver. It does not run through the ignition box like a lot of units the unit is modular and can accommodate an accelerometer and 2 to 4 wheel censers. This unit has been tested at one of the best racing schools in the country with unbelievable results. But Richard is right It is not a panacea for bad judgment. But it could potentially $ave your ride or your self especially in an over powered car. I am working on getting manufactures discount. We will pass the savings on. Any One know an insurance guy who can tell us if this could qualify for a discount?

[Richard Hudgins]

Bandit 1,

You stated the following:

"Where I do disagree with you is about the horsepower issue. It is totally logical for a dealership to "warn" you and see if you know what you are getting yourself in for, but please don't tell me what I can and can't handle."

I do not think that I have stated anywhere in my posts what you can handle or what you cannot.

It is obvious from your posts, that you can handle a vehicle no matter what the parameters involved.

Cool.

I wish that that I had this capabilty.

Alas. I never have.

[STG]

I've seen Richard's resume. The stuff he's left off (do a google search and find out which racing school he used to own!) would impress even the most jaded among us.

[Excaliber]

Richard clearly deserves a diplomatic trophy. You silver tongued rascal, LOL.

Ernie

[750hp]

Originally posted by Richard Hudgins


By installing traction control, you have in essence controlled (read reduced) the HP (or Torque) that the chassis will see in a dynamic situation. Exactly the correct thing to do with your engine/chassis combination. By using traction control you have taken an inherently unstable platform and applied controls that will allow this platform to remain in a stable longitudinal dynamic window.

With the Motec M800 I think that you are limited on the digital input side to 4 inputs for wheel sensors. I do not know if they can read the A>D outputs of two accelerometers and correlate with the wheel speed sensors to provide total traction control. But I am sure that OZVENOM will know how to do this and program them correctly. But with a manual throttle I do not know if a really effective friction circle system can be developed. But you can certainly make a single dynamic system work well.

Richard, thanks for the reply. You now have me intrigued as to the capablilities of the system for the racetrack. I was going to be content with simply applying the traction control based around the wheel speed sensors, but I'm going to send an email to Motec Tech to see what they have to say about the accelerometers and drive-by-wire throttle. I was concerned about the suitability of simply retarding ignition timing, as I believe that the motor will still be making 600+lb/ft with only 14 degrees TOTAL timing. The ignition cut seems like a brutal way to cut power, and I certainly can't see that it would help the chassis dynamics to have the engine hitting a soft rpm limiter mid corner . This leaves me with drive-by-wire, and mounting the throttle body before the supercharger to effectivey choke off the intake air supply. Much more delicate and effective, I'd assume...

"It's an OZ thing...." I might have a sticker made up for when I bring the car over for next year's Fling!!!

Craig

[Tom Wells]

Richard,

However, maybe it is fun to be able to light up the tires in third gear while driving down the freeway. Maybe it is fun to set off car alarms as you drive by.

But does any of that make for a really good road car?

Yes. Yes and yes

You had your misspent youth. Now let me have mine

Said with tongue quite firmly in cheek just to make sure you don't misconstrue.

My car has over 300hp. It does all the above nicely. It gets driven every day. I love it!

I also go to driving schools every chance I get.

I try very hard not to be stupid - can't guarantee the results - also can't stay home and hide under the bed

I mean this all in good spirit,

Tom

[casaleenie]

[quote]Originally posted by BANDIT 1


[b]Mr. Hudgins:
. For all we know the Cobra driver was minding his own buisness and the Trans Am pulled up next to him and "punched it" and lost control and crashed into the Cobra.



and I think they were both just driving along and a meteor from outer space fell on him... (it's just a theory of mine)

[wilf leek]

Casaleenie - that just plain ain't helpful. But I suspect you know that already. 'nuff said.

However - since we are talking about the engineering aspects of Cobras and the impact of that on their safety for street use, here is a particular "thing" that bugs me - Limited-slip or locking diffs..

To my mind, LSD just is not required for a street-driven Cobra. Absolutely necessary for track or drag strip, yes, but not for the street.
If you guarantee that both rear wheels will lose traction together with injudicious application of throttle, you are also guaranteeing a total loss of lateral stability.
Not something you really want if you are tight for space, or committed to a corner.
I might lose out on outright traction with my open diff, and for sure it annoys the heck out of me to spin away all the power from the inside wheel on a road course corner, but my car is 95% street driven, and I much much prefer a rear end that stays put to one that gets squirrely if I misjudge things (and don't we all sometimes, if we are honest).

No - I would rather that just one rear wheel breaks loose, leaving the other with some semblance of lateral grip.

JMHO, of course. I should be very interested to read the opinions of others with far better driving skills than I, and for sure there are a lot of them. Turk said it well elsewhere - I drive this car scared for my life. Might live a bit longer because of it.

[GeorgiaSnake]

Richard you are so logical you are causing me to feel guilty about my engine choice -----------------------------------------------------------------------------------nah.

Seriously, I think you are right on the mark. Most of the original cars had half the hp of what we are building today and they were a handful.

Must be ego driving the hp war One point about the modern cars (i.e. Porsche etc) they are light years ahead in engineering applications to handle high hp. The Cobra is a fifties design and most of the replicas have not evolved much.

Thanks for your insightful comments.

Randy

[Roscoe]

How does it go?

"Your ego's writing checks your body can't cash!"

Roscoe

[BANDIT 1]

Mr. Hudgins:

My comment wasn't totally clear. I wasn't saying that you were telling me what I can and can't handle, only that there are several on this forum that do. My statement was, that if people want to add safety items to a Cobra, I am all for it. I think that traction control is awesome (as long as it can be turned of...). However I disagree that anyone getting a 600 + horsepower is not going to be able to handle it. I don't think most wrecks in a Cobra come from "losing control" due to the power getting away from the driver.

Mr. Casaleenie:

The point was, "we don't know what really happened". I have driven many "fast" cars on the street and I know it is not uncommon ( in fact, very common...) to have a car pull up next to you wanting to race and then they "punch it" to show you what they have and to get you to want to race. I have seen on two occasions someone get "out of control" and get out of the throttle in a situation were I am just driving along minding my own buisness. I had a guy once in a early 90's GT Mustang (sounded like a really strong 351 c.i. engine) follow me through a stop light and proceed to "race me" (I was driving normal, and was NOT racing this guy in any shape or form of the word). He roars past me and then I hear the engine go "BOOM", it was night so you could see parts flying and everything.

[casaleenie]

[quote]Originally posted by BANDIT 1


Mr. Casaleenie:

The point was, "we don't know what really happened".


My point is that, although none of us were present at the time of the accident, it seems pretty clear that street racing was a common activity for the deceased.. I'm sure that the girlfriend and the other driver will swear that the race never occured.. That's what I would do... I'm sure the other driver will say he was just passing Glassnake and something happened.. He's not quite sure what exactly happened but it was beyond his control.. For insurance purposes a race never happened.. I would suspect that the insurance would be void if they were involved in street racing?????

[Tomsti]

HI, I am new around here and just in the planning stages of building a car. If the $$ works out :-) might take a little bit. However I was thinking that a 500 + HP machine would be the right thing to do (Not a daily driver, I live in the rain or cold 9 to 10 months of the year in Seattle). After reading most of the posts I still feel that this is the right thinking for me. Currently I race motorcycles (Not saying that I am any better then anyone else, just that I currently deal in low weight high hp machines). I ride a bike that I am estimating in race trim is at about 380 wet without me on it. Add 200 (Me) and you have 580 / 154HP = 3.76 lbs per HP that needs to be controlled on a very small patch of rubber, sometimes only one wheel is on the ground at 130+.

What I would like to say is… I shouldn't say this because now I will crash… Well, I am not known as a crasher (some guys are)… 4 seasons at this one time down because someone else hit me. I am at the tail end of our fast guys and seem to be able to keep the bike on two wheels. Reason…. I don't know, all I can think of is maybe the way I approach problems that you encounter pushing mass around track/street. There are guys out there that loose their minds and try things that really don't benefit them at all and it usually ends up with them on the ground.

When you add HP you really have to get rid of the red mist and start using finesse. Finesse and the knowledge of how your vehicle reacts to input. Hard to figure out from stoplight to stoplight.

HP isn't what kills it's the idiot behind the wheel.

Tom "idiot behind the wheel" Stimach.

[KobraKarl]

Hi tom,

Hope you get a car , I drive mine east of redmond a fair amount ,out fall city etc., Being a long time bike rider I can understand your point , but these cars dont begin to aproach the responce to braking and steering input that a bike will. My car is right about 500 hp ,I can honestly say the power to weight ratio is more of a hinderance than an asset , and iv'e driven hot rods and sport cars for 30 years........would I swap my side oiler for a mild 351??? .................no ,i dont think so , ..but I have been thinking lately, that a 289 car would be a more pure performance sport car.

see you around
Karl

[BANDIT 1]

Mr. Casaleenie:

Most people aren't use to the loud sound of a Cobra, if you just drive the speed limit in a Big Block Cobra it can sound like she is being very aggressive. To any "normal" person two "hot rods" next to each other is a race. Just because the gentleman "might have" raced in the past, doesn't mean he was racing on this night.