06-09-2018, 03:17 PM | #1 |
Drives: 2011 LS3 Camaro 2SS/RS Join Date: Aug 2015
Location: Colorado
Posts: 32
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High DA 1/4 mile times.
So 2 weeks ago I went to Bandimere Speedway and ran my car for the first time, only got 4 runs that night.
I started off with a 2.4 60' 14.08 @105 (pretty much a rolling burnout in 1st). 2nd run was 2.15 60' 13.71 @105. 3rd run was 2.21 60' 13.63 @105. 4th run was 2.12 60' 13.61 @105. Density altitude was ~8200' for these runs. Now last night at a track in lower elevation buy about 1000' (DA was still 7900') First run of the night was 2.0 60' 13.37 @108 Next 3 runs hovered around 13.5 ish all at 108mph. With 2.2+ 60'. I'd like to blame the 60' on the bald p zeros but I'm also experiencing some wheel hop so I have to pedal it sometimes. Anyway, I guess my question is did 300ish feet change in altitude really give me the extra 3mph? Or the .1 better 60'? And how is my mph compare to somebody at sea level? I'll update my sig later but car is '11 LS3 with catless long tubes, CAI, and RDP email tune (sct x4). |
06-09-2018, 03:38 PM | #2 |
Drives: 2015 2ss Join Date: Jun 2015
Location: Wooster ohio
Posts: 586
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200-250 feet change in da is generally about .01-.02 in et but the barometer and humidity also play a huge factor also
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06-09-2018, 03:40 PM | #3 |
Drives: 2015 2ss Join Date: Jun 2015
Location: Wooster ohio
Posts: 586
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Also different tracks we race at a track that is uphill from 1000 and beyond. So it's .1-.2 slower than other 1/4 tracks depending on weight of the car hp etc so mph difference could be based on that also
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06-09-2018, 07:05 PM | #4 |
Drives: 2011 LS3 Camaro 2SS/RS Join Date: Aug 2015
Location: Colorado
Posts: 32
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Wow never thought a track would be uphill. At Bandimere Speedway there's a very obvious "hill" at the end but looks like it's after the 1/4 to help you slow down I'm guessing.. but maybe the incline starts at the 1000 like you said. Would that account for .3 & 3mph difference? Also when you calculate for DA isn't that taking baro and humidity into consideration among other things?
I'm not complaining that I ran a faster time I guess I'll get a better idea once I get a bit more seat time. Side note concerning wheel hop: would it be a waste of time to do bmr trailing arms and leave the stock bushing in the knuckle? |
06-10-2018, 06:04 PM | #5 |
Drives: 2015 2ss Join Date: Jun 2015
Location: Wooster ohio
Posts: 586
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If it is uphill from 1000' it could be 3mph off for sure and possibly .3 et also but that also changes based on hp to weight too. A lighter car with lots of hp will be affected a little less from a slight incline where heavier car with less hp will be affected more by the incline.
As for wheel hop I'm not sure I have all stock suspension still with a 9" and I drop the clutch but never had a week hop problem. |
06-24-2018, 05:10 PM | #6 |
Drives: 2012 SS LS3 Join Date: Nov 2011
Location: NorCal
Posts: 818
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For what it's worth, I ran 10.40's in my stocker at Sonoma Raceway and 11.60's at Bandimere the next weekend.
You didn't mention wind. A 10 mph headwind changing to a 10 mph tailwind could give you a few mph.
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Buttonwillow 2:23.736
Sacramento Raceway 12.89 at 112 mph Thunderhill 2:22.242 |
06-24-2018, 11:59 PM | #7 |
Drives: 2015 Summit White 2SS 1LE Join Date: Feb 2012
Location: Vance Alabama
Posts: 8,019
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I do a 1000ft/.1sec in my head when Im at the track. Gets you in the ballpark.
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