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How far is speedo off with 4.10's and a 23 tooth gear?

  • Thread starter Thread starter NEEDA5.0
  • Start date Start date Apr 27, 2004

NEEDA5.0

Founding Member
Jun 13, 2002
563
0
0
Apr 27, 2004
#1
  • Apr 27, 2004
  • #1
So I installed the 4.10's and a 23 tooth speedo gear. According to my calculations I would actually need a 27 tooth gear to make the speedo accurate.

8 x 4.10 x 815
____________ = 26.732

1000

So, my question is how far is my speedometer going to be off with the 23 tooth vs 27 tooth?
 

94CobraPace

Founding Member
Aug 30, 2000
907
1
0
Houston, Tx.
Apr 28, 2004
#2
  • Apr 28, 2004
  • #2
It should be app 10% off, maybe 12%.
 

NEEDA5.0

Founding Member
Jun 13, 2002
563
0
0
Apr 28, 2004
#3
  • Apr 28, 2004
  • #3
Really? I was thinking alot more.
 
S

slytherin

New Member
Apr 5, 2004
702
1
0
52
northeast ohio
Apr 28, 2004
#4
  • Apr 28, 2004
  • #4
what tranny stock or after market, i,ve got the 3550 w/23tooth and my deputy sherrif buddy paced me down his road and my speedo was right on, those crown vics have certified calibrated speedos so i took his word on it.
 

NEEDA5.0

Founding Member
Jun 13, 2002
563
0
0
Apr 28, 2004
#5
  • Apr 28, 2004
  • #5
Its an automatic. There is no speedo gear that will compensate for a 4.10 gear in the AODE because the drive gear is an 8 tooth.
 
H

HazMat404

Founding Member
May 24, 2002
1,749
0
36
Apr 28, 2004
#6
  • Apr 28, 2004
  • #6
well i had a friend drive next to me with a walkie talkie when i got my gear install last year. i have the white tooth gear (think thats 23). with the stock auto and the t-5 in there now, i am 1mph off for every 10mph i go. works all the way up to 100mph too.

the mph should be more off the faster you go and there is no set amount of mph that you will be off.
 

LT1Killa

New Member
Oct 16, 2003
192
0
0
Apr 28, 2004
#7
  • Apr 28, 2004
  • #7
NEEDA5.0, How in the world did you go slower with 4.10's as opposed to the 2.73's?? Just curious.
 

NEEDA5.0

Founding Member
Jun 13, 2002
563
0
0
Apr 29, 2004
#8
  • Apr 29, 2004
  • #8
I didn't have a chip. The 2-3 shift was really bad. I just got the chip, so I'll find out this weekend what the 4.10's really did (if the rain stays away ).
 

AznStanger3v

Active Member
Aug 11, 2003
2,026
0
47
40
Northern VA
Apr 29, 2004
#9
  • Apr 29, 2004
  • #9
LT1Killa said:
NEEDA5.0, How in the world did you go slower with 4.10's as opposed to the 2.73's?? Just curious.
Click to expand...
damn, that was random.
 
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