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Old 10-27-2018, 05:25 PM   #1
gnicholson
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Default different ts ratio between 1/8and 1/4 mile

I have found in my limited experience of running 6.90 1/8th Mile index that the throttle stop ratio is higher which makes sense to me because it's on the stop a shorter period of time and each change is Amplified more. In the quarter mile my ratio is 2.8 to 1 and it's closer to 4 to 1 in the 8th mile. I was wondering if anyone else has ever noticed this? I'm on the stop a little over a second less than 4 quarter mile.

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Old 10-29-2018, 12:48 PM   #2
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Default Re: different ts ratio between 1/8and 1/4 mile

You should be able to answer this using all of your 1/4 miles runs. For each run after the first one on a given day, take the TS timer change and divide that by the ET change at the 1/4 and the 1/8 from the previous run.

Your results may be different than mine because I come off the stop in Low gear, but my ratios for the 1/4 and 1/8 end up looking very similar to each other on a run to run basis.

Congrats on the strong late-season performances and solid top-10 finish! I was watching 2nd round yesterday morning and pulling for you, so I understand why you may be asking this question.
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Old 10-29-2018, 02:55 PM   #3
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Default Re: different ts ratio between 1/8and 1/4 mile

thanks alot tony. i appreciate that. normally to run a 10.90 im right around 7.30 in the 1/8. I thought I had it figured out until that last run where my 60-foot was off .040. That was some of it. That track was all over the place. I seen a lot of people running way off the index along with some staggeringly bad reaction Times by a lot of people that are normally good. If I ever have to do it again I'll need some more data to make any kind of conclusion but there was three runs that pretty much agreed with each other that it was close to 4 to 1
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Old 10-29-2018, 06:30 PM   #4
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Default Re: different ts ratio between 1/8and 1/4 mile

We just had this issue at the LODRS race in Noble OK this past weekend. 2 TTs at 1/4 mile then we switched to 1/8 mile. The ratios are very close. If you look at where you are adjusting, it's at the same point for both.
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Old 10-29-2018, 06:55 PM   #5
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Default Re: different ts ratio between 1/8and 1/4 mile

i turn the stop on at .02 and have it on about 110 numbers less than in the quarter. my ratio seemed to change but im kind of suspicious of my results from noble. you say your car was pretty consistent there?
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Old 10-30-2018, 09:26 AM   #6
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Default Re: different ts ratio between 1/8and 1/4 mile

Quote:
Originally Posted by gnicholson View Post
...my ratio seemed to change but im kind of suspicious of my results from noble.
That's why I'd suggest looking at 1/4 mile runs from Topeka or somewhere that you know the car was good. You can see the 1/8 ratio and 1/4 ratio for the same run, and see if they are close or very different. It will almost never calculate to your actual ratio of 2.8 because of weather changes, but at least you can see how the two ratios relate to each other on a given run or set of runs.
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Old 10-30-2018, 10:56 AM   #7
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Default Re: different ts ratio between 1/8and 1/4 mile

i will look over a stretch of good quarter runs and see what the eighth did like you suggested. my point was i have to take out enough numbers to reduce my et approx 4 tenths in the eighth that it changes the ratio but i really need more runs. i doubt we do the 8th index again but you never know. im just curious about this basically
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Old 10-30-2018, 03:52 PM   #8
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Default Re: different ts ratio between 1/8and 1/4 mile

I see your point also, that if you change your stop duration by a bunch, the ratio could change along with it. Your stop duration was probably over 1 full second shorter than it would be to run 10.90.

I suppose there are a lot of guys who have run 10.90 and 9.90 with the same car who would know if the stop ratio is the same or different between classes.
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Old 11-10-2018, 11:10 AM   #9
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Default Re: different ts ratio between 1/8and 1/4 mile

I was able to do exactly what Tony mentioned and set up a new Db using the two 1/4 passes. Of course this required me to use the same stop rpm to make things work. But I ended up with about 50% less time in the stop doing it like this. Stop ratio was close to the same, maybe a pinch more.
One thing that I did not catch until Sunday was that I was coming off the stop before the 60' timer. Every adjustment I made to the timer affected the 60' time. Initially I thought track conditions were to blame, but it turned out that wasn't the case. 330' incremental numbers lined up. The right thing to do would have been to raise the stop rpm so I could carry a little more time and get past the 60' cone before coming off the stop. This way I could continue to use the 60' numbers to evaluate track conditions (which were suspect already). But when you're thrown a curve ball like we all were at that race you have to play the hand that you've been dealt.
I've promised myself that I'd work on a ideal 1/8 mi set up in case we get jacked around again like we did at TVRP.
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