Speed to wheelbase ratio

[Topcat]

Is there a general rule on how much horsepower to wheelbase ratio?

Car in subject is a 93 inch wheelbase, 3200 lbs.
At what speed/HP will it become unsafe...if at all?

I do know that shorter wheelbases tend to get scarier at higher speeds.
I would think there must be some type of engineering equation or scale chart.

[Alaskan_TA]

Aerodynamics would need to be known more than the wheelbase. Is it shaped like a bullet or a brick?

The variables are endless.

[71chally416]

There was a guy that ran a 9 second 454 Chevette at Atco years back. He sold the car and on the first pass the new owner barrel rolled it trough the lights and died. Lots of drivers have similarly met their fate in Vega's, Dodge Colts that were banned from pro racing after the death of Don Carlton and even Fox Mustangs.  I myself can think of better cars to go fast in than the short wheelbase cars. They are unforgiving when you get sideways at speed. That's why you don't see Pro Stock drivers get back into the throttle after shaking the tires and the funny cars and rails do with their long wheelbases, even multiple times on the same pass. Light weight is GOOD  SHORT WHEELBASE is not so good 

[Topcat]

Aerodynamics would need to be known more than the wheelbase. Is it shaped like a bullet or a brick?

The variables are endless.

The car in subject is my friends. An early El Camino body on frame, shortened wheelbase to 93". Last timeslip came in high 10's not totally dialed in yet.
SBC stroked.

He asked me today to see if I could find out anything about this for him.
I thought it was an interesting topic worth bringing up also.

[Topcat]

There was a guy that ran a 9 second 454 Chevette at Atco years back. He sold the car and on the first pass the new owner barrel rolled it trough the lights and died. Lots of drivers have similarly met their fate in Vega's, Dodge Colts that were banned from pro racing after the death of Don Carlton and even Fox Mustangs.  I myself can think of better cars to go fast in than the short wheelbase cars. They are unforgiving when you get sideways at speed. That's why you don't see Pro Stock drivers get back into the throttle after shaking the tires and the funny cars and rails do with their long wheelbases, even multiple times on the same pass. Light weight is GOOD  SHORT WHEELBASE is not so good 

 

It brings back a memory of doing 150 in a 280Z.
Was very drifty feeling at that speed.

[71chally416]

http://www.youtube.com/watch?v=4ATs6lBQtFs

[hebeegbz]

There was a guy that ran a 9 second 454 Chevette at Atco years back. He sold the car and on the first pass the new owner barrel rolled it trough the lights and died. Lots of drivers have similarly met their fate in Vega's, Dodge Colts that were banned from pro racing after the death of Don Carlton and even Fox Mustangs.  I myself can think of better cars to go fast in than the short wheelbase cars. They are unforgiving when you get sideways at speed. That's why you don't see Pro Stock drivers get back into the throttle after shaking the tires and the funny cars and rails do with their long wheelbases, even multiple times on the same pass. Light weight is GOOD  SHORT WHEELBASE is not so good 

what about sprint cars on dust they even make turns on half mile ovals and at one time they ran on 1 mile ovals at over 175 mph . i admit thoes guys have hundreds of hrs of track time instead of moments at a time . and yes the short cars are dicey and not for the novice. by the way this is a great post .

[71chally416]

Put a sprint car on asphault and put skinny drag race tires on the front and see what happens Sliding around on the dirt actually saves them from flipping more than they already do, and they do often.

[hebeegbz]

http://www.youtube.com/watch?v=4ATs6lBQtFs

 
wow did you notice the time it took for the safety crew to show up . i wonder how many minutes the driver has under his belt . this is not a dig but a concerned ex drag racer .

[hebeegbz]

Put a sprint car on asphault and put skinny drag race tires on the front and see what happens Sliding around on the dirt actually saves them from flipping more than they already do, and they do often.

you are spot on .

[Chryco Psycho]

I agree with all of the above , the shorter wheelbaase cars are unforgiving , but not nessisarily unstable , Areo plays a big part in stability as well

[hebeegbz]

After a good nap i had a thought, short cars need at least three things to keep the shinny side up. 1 hard side wall tires in front .  2 longer throttle travel .3 engine forward . some will say move the engine back for traction but in modern times we have so much tire and options to hook a car it becomes moot . also a long deck with side boards off the back like pro mods use will help keep a car straight . also to many racers run the tires to low ,listen to the tire manufactures about minimum pressures on slicks ,this will help on side bite when a car does get a bit goofy . and this is the big one the best drag racers i have ever met spent time in other racing forms to get seat time i.e. super bikes  ,any road racing ,best when wet . or at least a long course on driver development take a car out for a day and dump it till you stop loosing your lunch . you and or your friend will learn to know when to give up and remove your hands from the wheel and relax and dont forget to close your eyes ,it sucks to have some one put your eyes back in your head or some one hand your tonge back . my whole point is that fast race cars are no joke and i have lost many friend in racing over the last 35 years ,always thinks safe as for the camino sit down with an nhra tec guy hopfully an old one he will bring your car up to speed and help make your car the best that it can be with what your working with .in closing i started this season at the age of 50 with 35 years in racing its a milestone for me ,so race safe and good luck.

[heminut]

If you want to see the stability difference between long and short wheelbase cars then try to go to a race featuring both the nostalgia and modern class of fuel altereds! I attend the race at SIR in Tucson, and the nostalgia class is much wilder! The nostalgia cars have the short wheelbase, and are restricted to single plug heads and a 6-71 blower. Those cars are all over the track! The modern class has what is basically a funny car chassis (longer wheelbase and rear set engine) with some kind of a coupe body on it, and put out a lot more power because they are allowed much bigger blowers and dual plug heads. Compared to the nostalgia class these cars are a dream to drive!