2 Time Slips - What's the difference
 

This has been bothering me all weekend. I went to the track on Friday and ran a 11.54. My best thus far has been a 11.515. What is troubing me is that my trap speed is higher yet it doesn't look like my car picked up much speed in the 1/4 mile. If you look at the 60 ft. time it is .029 higher than my best and the 1/4 mile is .025 higher. Strange given the increase in trap speed in my opinion. Any thoughts?

Wow,

You are going to be amazed at this.


Your car produced more power in June, your run was faster. Your March run was at a highly negative DA producing faster times than normal. Like if you had a tail wind etc. Your cars times throughout the slip in June are better than your March times.



The closest weather results for 06/15/2007 at 09:43 pm

Time recorded 9:35 PM
Temperature °F 60.8Dew Point °F 48.2
Altimeter Setting 30.07 in Mercury
Density Altitude: 208.3 feet
Track Elelvation: 86 feet

UnCorrected ET:
11.54 (sec) @ 123.69 (MPH)


Corrected ET to Sea Level:
11.515 (sec) @ 123.967 (MPH)

Your run in marcch was actually slightly slower when correcting to standard condition.


Your car was producing more power in June due to more favorable air temp. Although the car seemed faster in March when looking at the slip it was actually slower because of the DA of negative -959. Here is the corrected slip in MArch

The closest weather results for 03/31/2007 at 01:01 pm

Time recorded 12:55 PM
Temperature °F 48.2
Dew Point °F 19.4
Altimeter Setting 30.27 in Mercury
Density Altitude: -959 feet
Track Elelvation: 86 feet

UnCorrected ET:
11.515 (sec) @ 121.91 (MPH)


Corrected ET to Sea Level:
11.631 (sec) @ 120.653 (MPH)

Had you had your car from the June run run at negetive DA you would have run 11.315@125.7


Your run in June without a question was faster so your car produced power more effectively

The 60ft is everything, its hard to make up any ground after that with-out alot more power. You were definitely making more power on Friday, you were gaining ground as your incrementals were getting smaller compared to your previous run but not enough to overcome a .029 deficit. If you look at your 1/8 trap speed you only gained .81 mph over your previous run and stretched out the average to 1.78 mph out the back door, to little to late as far as et is concerned.

Thanks... this is very helpful.. My headache has gone away... :)

Juicee63,
This is very helpful. What is the difference between the March and June run? About 80 pounds in unsprung weight, or about 320 pounds in static weight. Most people say that reducing 320 pounds in static weight is equivalent to adding 32 hp which can add 3.2 mph to your trap speed. I think that is what we are seeing here.

...........I agree that it is all in your 60ft time. For the same et, the run with the slower 60ft time will have the higher trapspeed. The idea is that your car has more distance to cover allowing it to get to a higher speed at the end of the 1/4 mile.

Ted

Great , I am doing this as well with lighter wheels. Hopefully I can get 80 lbs off. My car is way too heavy. 4600 plus ew! So yeah it really helps to look at the DA. If you do not you would likely be depressed that your weight reduction did nada. The DA changed by over 1000 ft from your run in March to the 1 in June. Even with forced induction 1000 feet will effect your car.

Awesome runs BTW. Wicked fast ride you have

Very true..
we agree again LOL

welcome to the quarter, you're a time slip whore......

Sleeper, nice run bud. It sounds like the Evo rotors and light weight wheels are making a difference.


Try this experiment the next time you are at the track. Instead of attempting to come out of the hole hard to get the best 60ft time. Attempt to shoot for your best trap speed. I'd be interested to see what happens if you don't rocket out of the gate so hard.


Juicee, nice post my friend........a lot of good information there.

Thanks Rock! I think in better weather conditions, October - March, I can trap at 125mph. We shall see. Unfortunately, it is getting too warm here in the next few months to break any records.

sick sick traps man:bow:

Thanks Jay. That means a lot to me coming from the fastest CL600 in the country..... I think it is time to take the street tires off and get D/Rs.

damn that was on street tires:eek: wow very impressive, yeah put some real rubber on there and see what it will do

Im sure with some drags you can get your et down a tenth or 2. your trap speed may have increased but that doesnt change the fact that our cars are limited to how hard we can get out of the hole. 60 is the key in low et's. if these cars were able to stall speed at a higher rpm with some slicks we would see alot of 10 sec passes. thats why Nitrous is the only other way to make up for it once your out or the whole.

and a LOT of broken drivetrain parts! these cars are easily capable of 1.6x 60ft times with d/r's...how much quicker off the line do we need to be?

i think we'll see a few non n2o 10 second passes once we get a reliable i/c cooling set-up.

How do you get thos 1/4 times...DO you use Drag radials ???

I run on Toyo Ra1s. It is a R compound tire that you can use on the street. They are my everyday tires.

What mods do you have aqnd what size tyres do you run, pressure etc ???

Do you do burn outs ???

Do you lower the tyre pressure ???

ESP on or OFF ???

At which RPMS and how do you launch ???

Thanks:y

..........do you use the ra1's for both the front and rear or do you use regular tires for the front?

ted

I use Toyo Ra1 in the front and rear. No LSD needed!!!

check your PM

May I know your tyre sizes and widths as well? Those are amazing times for street tires and no LSD!

245/40/18 in the front
275/35/18 in the rear

......Respect!!

Ted