6speedonline's official 60-130, 1/4 Mile, and Standing Mile list
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I would also love to see a dyno comparison, same dyno, same day for some of these monsters (like perhaps at a 1-mile event).
Btw, is there any greater error/reading variance in the 1000+rwhp levels vs. the lower rwhp range?
Btw, is there any greater error/reading variance in the 1000+rwhp levels vs. the lower rwhp range?
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Well, the TTGs are dynoed on Dynojets with the front driveshaft removed, while the GT-Rs are dyno'd in their AWD configuration, but no matter how you slice it...the Stage 'R' TTGs are putting down quite a bit more power overall. They are quite impressive cars..
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I really don't think it pulled 2.4 g's of acceleration, I don't think that's feasible on the street, especially with R888's (which are designed more for lateral acceleration, not longitudinal) which I've driven on a road course. For reference a Top fuel dragster pulls 4.5 G's
P-box uses GPS to calculate everything. There are no accelerometers. Any math majors or fellow engineers out there? Change in position over time = speed. Change in velocity over time = acceleration
The sampling rate of the GPS is in the P-box and all the other consumer grade devices from Race logic is 10hz, so 10 samples per second. This is taken right from the P-box specifications in the manual. Absolute positioning is 5m diameter (16.4 feet) 95% circle of error probability. Meaning that 95% of the positioning will be in a 16.4 foot diameter circle. They do say that distance measurement is accurate to within .05% But I just calculated the data from our V-box and P-box that were in our car on the exact same run, and the error is more than that.
The p-box and v-box is a great tool but the closer I look at our #'s and the discrepancies we showed when we ran both units in our car the same time, the more I see that if you're trying to get accuracy to the .1 of second or less, there could be some accuracy issues.
I've used a lot of different dataloging systems that use either GPS and/or accelerometers (Motec dash, AIM, Race Pack, p-box/v-box, Chase cam, Race keeper, etc) and that data is never 100% accurate or perfect, especially when compared to dedicated track timing equipment (road course or drag strip).
-Martin
P-box uses GPS to calculate everything. There are no accelerometers. Any math majors or fellow engineers out there? Change in position over time = speed. Change in velocity over time = acceleration
The sampling rate of the GPS is in the P-box and all the other consumer grade devices from Race logic is 10hz, so 10 samples per second. This is taken right from the P-box specifications in the manual. Absolute positioning is 5m diameter (16.4 feet) 95% circle of error probability. Meaning that 95% of the positioning will be in a 16.4 foot diameter circle. They do say that distance measurement is accurate to within .05% But I just calculated the data from our V-box and P-box that were in our car on the exact same run, and the error is more than that.
The p-box and v-box is a great tool but the closer I look at our #'s and the discrepancies we showed when we ran both units in our car the same time, the more I see that if you're trying to get accuracy to the .1 of second or less, there could be some accuracy issues.
I've used a lot of different dataloging systems that use either GPS and/or accelerometers (Motec dash, AIM, Race Pack, p-box/v-box, Chase cam, Race keeper, etc) and that data is never 100% accurate or perfect, especially when compared to dedicated track timing equipment (road course or drag strip).
-Martin
Not sure why you want to pick apart the G readings on a Pbox. It's an accepted measurement of 60-130's. We might as well be arguing about the differences in dynos.
Anyway you look at it - with or without the Gs' - 3.04 is fast.
-Eric
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I'm not contesting the run, just curious about the G spike, since the Pbox calculates G's from GPS position. I've been racing, developing cars, etc for years and have been looking at data from all sorts of data acquisition systems and when I see what to me looks like an anomaly I try to figure out why.
They won't release the file but now the distance has been posted on the graph, which is what i wanted to see. All good.
-Martin
They won't release the file but now the distance has been posted on the graph, which is what i wanted to see. All good.
-Martin
have you seen a spike like that from a drag car with a vbox?
just curious
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Ha ha...of course that won't happen. GT-Rs are running 60-130s that are within 3/10ths of a second with 300 less whp, 200 lbs more weight, during 1/4 mile runs (which produce times that are almost always slower than during dedicated 60-30 runs). GT-Rs will continue to get more powerful and faster at an exponential rate.
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