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94bird
02-01-2014, 06:49 AM
While working on my tune last summer i completely neglected to adjust the fuel cut off. It was still set to 5800 rpms even though i was shifting at 6000. Could this explain my somewhat disappointing times?
Also, on data master does anyone have any input on how accurate the 0-60 and dyno numbers are?


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sweet-94z28
02-01-2014, 09:52 AM
You will know when you hit the rev limiter (fuel cutoff). The LTX computer can be a little bit slow in cutting off fuel and commanding shifts. I always set them to 6200 on a stock bottom end.
Injuneer
02-01-2014, 12:28 PM
What were you using for the RPM? I found the stock tach was a couple hundred RPM higher than actual engine RPM, when compared to a scanner reading the PCM. As noted, you would notice if the PCM cut fuel.... bammmmm! Like hitting a brick wall.
sweet-94z28
02-01-2014, 01:10 PM
My bone stock 94 Z28 I had read 6100 RPM with a WOT shift on the stock tune. On logging software, it showed 5700. So that's 400 RPM off.
94bird
02-01-2014, 01:42 PM
I am going by the shift points in the log
I moved them up to 6200 as well but ive never felt that "wall" lol but i noticed on the data master dyno graph the power tails off fast after 5700. I wasn't sure if that was just the stock cam running out Of juice or if it was because the fuel cut off

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Blackbird96WS6
02-01-2014, 02:24 PM
I am going by the shift points in the log
I moved them up to 6200 as well but ive never felt that "wall" lol but i noticed on the data master dyno graph the power tails off fast after 5700. I wasn't sure if that was just the stock cam running out Of juice or if it was because the fuel cut off

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Probably the stock cam running out of juice, mine does the same thing. I ran high 14s trying to shift mine (manual) at 6-6100 vs running 14.4 when shifting at 5700 and then running out 3rd gear to 6k to cross the line.

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SSlowBoat
02-01-2014, 02:48 PM
I have the shift for the heads cam car at 6000 with a rev limit of 6500 and the tach buries itself wide open on a shift without hitting rev limiter, dont trust stock gauges.
94bird
02-01-2014, 03:08 PM
Probably the stock cam running out of juice, mine does the same thing. I ran high 14s trying to shift mine (manual) at 6-6100 vs running 14.4 when shifting at 5700 and then running out 3rd gear to 6k to cross the line.

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The only thing that makes me question whether or not theirs more power to be had past 5800rpms is because it's a FI car

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Blackbird96WS6
02-01-2014, 03:32 PM
The only thing that makes me question whether or not theirs more power to be had past 5800rpms is because it's a FI car

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Oh, didn't see that bit lol. My bad.

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