05-20-2017, 12:39 PM | #1 |
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Drag strip woes
I went to the drag strip last night, and while nobody there was running spectacular times, I noticed that compared to last year I was having a hell of a time trying to get traction.
The track was Castrol Raceway in Edmonton, elevation somewhere around 3800 ft. Temp started at ~60 and went down to about 50. Car was running Shell 91, tires at 22psi. The problem was obviously traction. It was too cold to hook up. But I did notice that when I got to about 5500 RPM in 2nd, the car felt like it shut off. Didn't do that in 3rd or 4th. Best time of the night was 13.79 @105. Best 60' was 2.28. How do you guys with manuals launch? Last night I found running with the car in sport+ ran the best. I'd hold about 2000 RPM and feather the clutch out, otherwise it was massive wheel spin or wheel hop. Last year my best et was 13.05 @114, I think my 60' was around 2.1.
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05-28-2017, 07:12 PM | #2 | |
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Quick question though, was it the same track both times? Even if traction was a issue the loss in trap speed is what has me a little confused. Losing 9mph in the 1/4 is brutal. Any mods? |
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05-28-2017, 08:02 PM | #3 | |
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05-29-2017, 09:53 AM | #4 |
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05-29-2017, 08:22 PM | #5 |
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Same track. Only mod is the catless down pipe. I think it has the compressor wheel spinning up too fast, the MAP is probably reading too much boost then wasting.
I don't have this problem on the street, but I'm also not opening up like this in traffic. I think I need a tune to allow for higher boost/faster spooling. Then I can data log to see what's happening. I've heard a few others talking about the car going into limp mode because of down pipes, maybe mine is just on the verge.
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05-29-2017, 09:22 PM | #6 |
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Are you capturing any type of data right now? With a Performance Analyser or Torque App for example?
I see you are running 91 octane, how good is the gas in your area? I am thinking like someone else mentioned above, might be pulling timing because its sensing knock?
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05-29-2017, 10:44 PM | #7 | |
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05-30-2017, 07:22 PM | #8 | |
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I didn't have any problems in any other gear, just second
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05-30-2017, 07:28 PM | #9 |
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Well I have done pulls where the car lost traction and I feel like its DSC kicking in to get the rears to hook again. It does happen mostly in 2nd gear while running in Sport+ where DSC is just partially off. But it feels like its just cloaong the throttle or something because the car basically halts the acceleration for a full second.
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05-31-2017, 06:47 PM | #10 | |
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Something is up for sure though, the loss of mph in the 1/4 is substantial. People have posted dyno's with a little e85 added and they pick up power and get a cleaner powerband from just the 91oct piss fuel. |
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