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Old 09-06-2009   #1 (permalink)
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Default calculations are incorrect for mph
I am running 3.73 gears, 26x10-15 slicks and crossing the line 11.97 and 113.49 mph at 6600rpm on my tac?
These numbers don't work out right on any calculator I try. I should not be turning so many rpm crossing the line. Whats up?
I should be crossing around 5600 instead.
Does the converter change things?
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Old 09-07-2009   #2 (permalink)
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your stall converter has a lot to do with it. or if the converter is going bad you could be driving through it
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Old 09-07-2009   #3 (permalink)
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My first question what tach are you using.......
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'88 LX Hatch With A Little Of This & A Little Of That......
10.39 @128 MPH Soon to be faster....
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Old 09-07-2009   #4 (permalink)
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Yes there is something up with the converter. I'm going through that little myself.
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Building it right from the beginning is always better than starting over to build it better because it was temporary.

93' LX hatch, 460 with mods, TH400 trans, 9" w/ 3.89 spool. Best (so far!) of 10.18 @ 131 mph with 1.39 60'

Reese,
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Old 09-10-2009   #5 (permalink)
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Seems like the tac is 300-350 rpm off. I will check it. The 9psi in the slicks makes them wrinkle a lot just sitting there. If you measure the radius from ground to center of axle it makes it about a 24" tire. I will air up next time I run it and see if that helps.
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Old 09-12-2009   #6 (permalink)
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stock or aftermarket tach?

when my shift lite comes on at 5400rpms on my 5" monster tach,my stock tach reads 7000rpms..no kidding...
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Old 09-13-2009   #7 (permalink)
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Quote:
Originally Posted by need4spd90 View Post
stock or aftermarket tach?

when my shift lite comes on at 5400rpms on my 5" monster tach,my stock tach reads 7000rpms..no kidding...

I believe you......
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10.39 @128 MPH Soon to be faster....
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Old 09-14-2009   #8 (permalink)
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Sun Monster tac with shift light.
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Old 09-15-2009   #9 (permalink)
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Quote:
Originally Posted by lilorange79 View Post
Sun Monster tac with shift light.
My opinion, I would use Autometer guages.
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Building it right from the beginning is always better than starting over to build it better because it was temporary.

93' LX hatch, 460 with mods, TH400 trans, 9" w/ 3.89 spool. Best (so far!) of 10.18 @ 131 mph with 1.39 60'

Reese,
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Old 10-24-2009   #10 (permalink)
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4-10 gears with 5-speed and 26'' tires i trap 6700
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