I need a little Drag Racing 101.

I've noticed cars that race with different times, and different miles per hour. The thing I don't get is who is faster?

Like use this as scenario (#1):
Car A
10.134
@126.9mph

Car B
10.134
@94.8mph

They both got to the finish line at the same time, but were traveling different speeds. How is that possible? Who is actually faster?
-------------------------------

Another scenario (#2):
Car A
12.564
@101.3mph

Car B
15.784
@101.3

How is it that they got their at different times, but were at the same speed? Who is actually faster?

...
So far from what I've noticed if you have a fast time but very low mph (82mph). You most likely have small gears (3.73 or so).
But if you have big gears (2.77 or so). You will have a slower time, with higher mph (101mph). Why is that?

How is it possible that two cars can be going the exact same speed as the other, BUT one will get to the end of the track quicker? I don't know if it boggles others, but it seems to boggle mine??
Any help is appreciated thanks!

 

It depends a lot on how the car is set up. When I originally bought my car it has a 383, 26" tall slicks and 3.27 gears. I got it as quick as 11.8's at 117 mph. At that same ET cars were usually running 108 mph. I was geared all wrong. It was hard for my opponents to judge my speed. When they were almost topped out by the 1000 foot mark, I was still building speed and getting ready to pass. I think the car would have topped out by the 5/8 mile point but the track isn't that long.

My current setup has me running 11.6's at 115 mph. I shift at my red line and cross the finish line with the shift light already on. With high gearing and a very high stall converter, mph will be a lot lower than normal.

In scenario #1, car A has HP to run that quick while car B has the gearing to do the same ET. Car B looks like a bad combination if it's doing less than 100 mph and running 10's.

in scenario #2, car A has a good setup. Car B has the HP to run over 100 mph however must have some highway gears and a stock converter to only run high 15's.

None of your poll choices are valid numbers. You'll never see that combination of ET and MPH unless something is wrong.

 

depends on how you judge what is "fast". there is a big difference between a quick car and a fast car. quick is all about e.t.'s, fast is all about power. anyone can build a car that can run a huge mph, but a quick car will run an e.t. to match it.
like stephan running 11.6 @ 115mph. that is a car that sounds like it is well matched and hooking up good. prolly cutting 1.60 to mid 1.5 60ft times. that is a car that is both quick and fast.

later
tim

 

I got to watch a promod tonight. Top Alcohol funny cars were running 6.7's at 175 mph. The promod ran 5.98 at 212 mph.

Go to the other end of the scale. Land speed record cars are not quick but they're fast. A car that can do 200 mph on the salt flats would probably only run 15's in the 1/4 because it isn't geared the same.

A fast car on the highway isn't usually a quick car on the dragstrip. Drag cars are not usually concerned about mph. If you can get down the track in 12.0 at 108 or 12.0 at 115 doesn't mean much since it's a bracket race all that matters is the ET.

My 60' times have been in the 1.6x range. I think I have a bit too much converter to get into the 1.5's until I get the chassis dialed in again.

 

Obviously 147 mph is faster than 98, but a 10 second quarter mile is quicker than a 14 second one.

 

I think the mph in the quarter has to do with the car's purpose and how it was put together.

I'll explain what I mean:

Say you have a drag-only car that never sees the highway and hardly is ever driven on the street: you wouldn't mind a 3500rpm TQ converter or 4.56 gears or slicks. Those items help with ET but erode mph due to friction, pumping losses (converter slippage) and being overgeared. The car might run 11.9 at 111mph, being topped out in revs for the last few hundred feet. Say you have the same motor with a 2500rpm converter, 3.42 gears and drag radials running 12.3 at 115mph. Obviously the car is running 0.4s slower, but 4mph faster. The first car is using its power to produce ET (at the expense of mph), the second car gives up some ET to keep a good mph. In 2002, the pendulum is pushing toward the second car since the first car is done at 111mph (top speed) and the second might do 130mph (not counting OD gears).

Of course there are other factors:

Traction problems
Being undergeared/way overgeared
Transmission slippage & inefficiency (also very heavy flywheels)
Really bad aerodynamics (vans & old cars especially)
Badly mismatched engine combinations

Personally I would rather give up a few tenths in ET to keep the car more streetable and not rev too high on the highway.

 

rezinn, you're right. it doesn't have much to do with dragracing, just english.

 

One question I have is how is it possible for 2 cars to reach the finish line, AT THE SAME TIME, HOWEVER DIFFERENT SPEEDS??

Like for instance a funny car, running off of an engine, would do like 5 @220mph. While a funny car, running off a JET engine. Would run a 5 @315mph.

How is it possible that both cars are parallel to each other, right next to each other crossing the finish line, YET one is another 100mph faster??

 

One car could get to a higher speed quicker, yet not accelerate in the top end, and the other could get to a higher speed right at the end of the 1/4.

My street car runs 14.15 @ around 98 mph. When I run against Supras, we get to the line at the same time, around 14.15... but they're running around 110 mph. During the run, I pull 2 car lengths off the line from torque, I get to my speed quicker, but I have no top end, so I get to around 75 mph and start to accelerate slower. A Supra leaves the line slower because they have little torque until the turbos spin up, so at around 1000 feet, they blow past me. They make their power in the higher RPM range.

If you graphed the change in speed over time, my car would have a sharp rise at the beginning, then a gentle rise from the middle to the end. The Supra would have a gentle rise from the beginning, but would shoot up towards the end. Same times, different speeds.

 

If a car breaks or hits the brakes (bracket racing), you can have a very low ET with low MPH. I've watched a Mustang run 9.20 at only 101 MPH because he blew the motor.

 

I not a drag racer but, don't they attain your speed via a trap (between two lights) torwards the end....I seen top fuels run 7 sec @ apox 100 mph on T.V., because of problems before the speed trap, like pulling the shoots early...My self I voted for the first one..it covers the 1/4 in the shortest time and since your "only" going 98 mph you'll be through a turn sooner than the other person braking from 147 mph. I would think some were down the road the 147 guy would catch and pass, Just my thoughts..

 

i have this crazy hillbilly friend. all he wanted was a car that could do wheelies. he got a mustang, dropped in a 514" 8-71 motor. 5000 stall, 7.08 gears, 33" slicks. without the bars on, it would flip over. did a wheelstand like nothin. topped out at 85mph. ran 12 second 1/4's at 85mph. an absolute terror in the 1/8 though.

 

GO RICE BOY

 

That's great! I love it!