[MarioKart]

I love going to the track but I'm horrible in math, can someone explain how a faster 60' time results in a slower MPH at the end of the 1/4 mile?
Here are my results at my last track event
1st run 2.02 60' @12.52 @ 113mph
2nd run 1.7 60' @ 12.55 @ 111mph

How does this work?
TIA
Mario

[daixloxbmw]

i am no expert but i would guess traction vs power.

having slightly less power will give you better traction for the 0-60 but decrease trap speed.

having slighly more power will give you higher trap speed but may decrease traction for the 0-60.

[MarioKart]

Originally Posted by daixloxbmw

i am no expert but i would guess traction vs power.

having slightly less power will give you better traction for the 0-60 but decrease trap speed.

having slighly more power will give you higher trap speed but may decrease traction for the 0-60.

But we are talking about the same car on the same day with the same amount of power. Both times when I nailed the pedal on the last yellow, I never spun the tires. I launched at 2100 rpm both time on drag tires.

[sleepdoc]

Originally Posted by daixloxbmw

i am no expert but i would guess traction vs power.

having slightly less power will give you better traction for the 0-60 but decrease trap speed.

having slighly more power will give you higher trap speed but may decrease traction for the 0-60.

The OP is tallking about the same car with the same power. It is true that a lower 60' usually leads to a better ET, but a slower mph. I have yet to hear a really nice explanation of why this occurs..

[K330i]

how long in between runs>?

if you don't give enough time between runs you will be slower with each pass.

nothing sucks the performance out of a motor like heat.

btw: nice 1.7 launch...keep it up!!!

[vegasspeed]

The lower the 60' time with a stock car the faster you will cross the line before getting up to full speed. If it is the same car and you increase your 60' time chances are you won't need as much speed to pass the 1/4 mile line.

[MarioKart]

Originally Posted by K330i

how long in between runs>?

if you don't give enough time between runs you will be slower with each pass.

nothing sucks the performance out of a motor like heat.

btw: nice 1.7 launch...keep it up!!!

They were about one hour between runs and the weather was around a cool 67F. But this fact of a faster 60' time has always confused me.

[vegasspeed]

Think of it graphically.
A-----------------------finish
B----------------------finish

B is ahead due to the quicker time so I would assume he doesn't need as much speed to cross the line as A would. Just my two cents.

[jworms]

Originally Posted by vegasspeed

The lower the 60' time with a stock car the faster you will cross the line before getting up to full speed. If it is the same car and you increase your 60' time chances are you won't need as much speed to pass the 1/4 mile line.

Originally Posted by vegasspeed

Think of it graphically.
A-----------------------finish
B----------------------finish

B is ahead due to the quicker time so I would assume he doesn't need as much speed to cross the line as A would. Just my two cents.

very good explanations and they are true...to an extent. There are cases that don't follow these 'rules' like when you have a horrible 60ft time (think low to mid 2s and beyond) compared to a 2.0 or lower. this is because you spent your time spinning off the line instead of accelerating, which actually hurt your trap speed.

it's all about finding that 'efficiency range' for 60ft times that will yield optimal trap speeds.

[BALLAJL15]

That was just a weird night... I hit 12.50 only at 109.... with a 60' foot of 1.8

[TheSpungos]

Originally Posted by MarioKart

I love going to the track but I'm horrible in math, can someone explain how a faster 60' time results in a slower MPH at the end of the 1/4 mile?
Here are my results at my last track event
1st run 2.02 60' @12.52 @ 113mph
2nd run 1.7 60' @ 12.55 @ 111mph

How does this work?
TIA
Mario

If you're basing it on these 2 times, something else may have been the issue. You are actually slower on the run with the better 60' time, in addition to trapping lower. The small variable that led to the slower time may have also affected your trap speed.

[raceyBMW]

You can also lose time in shifts down the line. Don't know if you drive an auto or not, but letting the car automatically shift at redline vs. manually shifting the auto at ~6000rpm can result in a lower speed at the end. It is not going to make much difference in the shift from 1-2, but will in the higher gears. Because of this, you might see the same 0-60 time where the trap speed is slower letting the car auto shift at redline. Same deal will work with a manual too.

[sflgator]

Not entirely sure, but great times though!

[mistermojorizin]

correct me if i'm wrong, but

lower 60foot = lower ET

lower ET = less time to develop speed

therefore, ceterus paribus, lower 60 foot = less speed

[sflgator]

Originally Posted by mistermojorizin

correct me if i'm wrong, but

lower 60foot = lower ET

lower ET = less time to develop speed

therefore, ceterus paribus, lower 60 foot = less speed

Makes sense.

[BavarianBullet]

Originally Posted by MarioKart

I love going to the track but I'm horrible in math, can someone explain how a faster 60' time results in a slower MPH at the end of the 1/4 mile?
Here are my results at my last track event
1st run 2.02 60' @12.52 @ 113mph
2nd run 1.7 60' @ 12.55 @ 111mph

How does this work?
TIA
Mario

2 runs aren't a statistical sample. You also really need to spend time looking at the whole timeslip especially the 1/8th mile numbers.

Even if you trapped slower on the second run you still should have posted a roughly 12.2x run if the 60ft was 3 tenths faster and everything else was the same.

If you looked at the 1/8th mi numbers and noticed that your car was 90mph in the 1/8th on the 113mph 1/4 and then 88mph 1/8th on the 111mph 1/4 you'd know you gave up some power in the first half of the track. If it all happened at the end of the track, different factors could have contributed to it such as a high water temp or air temp pulling timing for example.

Post up the whole timeslip (numbers not scan) so we can take a look at it.

Great times regardless though!

[Dan335i]

Foreget about the whys,and just get your 60ft times down and you will see your 1/4 mile times drop.

[MarioKart]

Originally Posted by mistermojorizin

correct me if i'm wrong, but

lower 60foot = lower ET

lower ET = less time to develop speed

therefore, ceterus paribus, lower 60 foot = less speed

It looks simple but it seems like with a lower 60' I would be getting up to speed quicker = a higher trap mph

[MarioKart]

Originally Posted by BavarianBullet

2 runs aren't a statistical sample. You also really need to spend time looking at the whole timeslip especially the 1/8th mile numbers.

Even if you trapped slower on the second run you still should have posted a roughly 12.2x run if the 60ft was 3 tenths faster and everything else was the same.

If you looked at the 1/8th mi numbers and noticed that your car was 90mph in the 1/8th on the 113mph 1/4 and then 88mph 1/8th on the 111mph 1/4 you'd know you gave up some power in the first half of the track. If it all happened at the end of the track, different factors could have contributed to it such as a high water temp or air temp pulling timing for example.

Post up the whole timeslip (numbers not scan) so we can take a look at it.

Great times regardless though!

Thank you,
I know I have at least one of the time slips, but I will look for them so I scan them

[mistermojorizin]

Originally Posted by MarioKart

It looks simple but it seems like with a lower 60' I would be getting up to speed quicker = a higher trap mph

i don't think you would be getting up to speed quicker. at least not necessarily. you're just wasting less time at the starting line by not spinning tires or bogging. but to keep from spinning, you're also not putting down as much power.

[hotrod182]

My trap speed went up with DRs. when the 60' time went down.

On DRs

12.133 1.729 113.49mph
12.261 1.80 112.40mph

On Stock RFT

12.633 2.00 111.22 mph

[Zeph]

because if you spin your tires more, you leave the line at a higher rate of speed and therefore in your 1/4 of a mile stretch you go from say 20mph-110 or with more spin you might go from 25-112

that is what I have always thought.