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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

New gears, but can't set speedo

  • Thread starter Thread starter tradde
  • Start date Start date Aug 4, 2005
T

tradde

New Member
Aug 2, 2005
94
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0
Pennsylvania
Aug 4, 2005
#1
  • Aug 4, 2005
  • #1
Hello all. This is my first post here. But I have been reading this board for some time. Lots of useful info here. I finally upgraded my gears from stock 3.08s to
4.10s on my 2000 GT vert. The guy who did the swap attempted to set my new
rear ratio using my Hypertech Power Programmer III. I drove off and the speedo
was way off. I assumed he had not set it right. He admitted he could have done
something wrong. I tried it when I got home and know I stored in 4.10s and
it even displayed my changes and showed 4.10s. But the speedo is still off
by quite a bit. Nothing else was changed. Any ideas. Maybe the tires that
are on it are not stock height? They were on the car when I bought it used.
Brand new in fact. I could live with a few mph off. But this is waaaayyyy off.
Thanks for any hints.
 

Skidzz

Tinkerbell
Apr 11, 2005
328
1
19
Salt Lake City, UT
Aug 4, 2005
#2
  • Aug 4, 2005
  • #2
Well from what I understand, the hypertech programmer is teh suck. That may be your problem. I suggest just buying a speedcal for $100. I also suggest getting rid of the hypertech and getting a preditor.
 
J

jamez1502

Banned
Nov 6, 2003
135
0
0
Lakeland Fl
Aug 4, 2005
#3
  • Aug 4, 2005
  • #3
but the programmer will fix ur speedo...
 
T

tradde

New Member
Aug 2, 2005
94
0
0
Pennsylvania
Aug 4, 2005
#4
  • Aug 4, 2005
  • #4
Can't set my speedo

Skidzz said:
Well from what I understand, the hypertech programmer is teh suck. That may be your problem. I suggest just buying a speedcal for $100. I also suggest getting rid of the hypertech and getting a preditor.
Click to expand...

Ok, first what is this speedcal thing? I have seen it mentioned before in other
posts. If I do indeed get the Preditor will I still need the speedcal? Do you think
the shop that did the gear would have that? He mentioned something for about
that price when he asked me if I had some type of programmer. Thanks.
 

csledd

Official Ovary Punching Member
Founding Member
Aug 18, 2001
1,115
1
0
Paducah, KY
Aug 4, 2005
#5
  • Aug 4, 2005
  • #5
speedcal adjusts your speedometer. If you get a Predator you shouldn't need a speedcal. Also consider the SCT Xcalibrator 2
 
T

tradde

New Member
Aug 2, 2005
94
0
0
Pennsylvania
Aug 4, 2005
#6
  • Aug 4, 2005
  • #6
tradde said:
Ok, first what is this speedcal thing? I have seen it mentioned before in other
posts. If I do indeed get the Preditor will I still need the speedcal? Do you think
the shop that did the gear would have that? He mentioned something for about
that price when he asked me if I had some type of programmer. Thanks.
Click to expand...

Ok, I ordered the Predator. I wish I had known this before I bought the Hypertech.
Oh well. live and learn.
Tim R
 
J

jamez1502

Banned
Nov 6, 2003
135
0
0
Lakeland Fl
Aug 4, 2005
#7
  • Aug 4, 2005
  • #7
yep ull love the predator i did...
 

Green&GoldGT

Member
Aug 1, 2005
302
0
17
Virginia
Aug 5, 2005
#8
  • Aug 5, 2005
  • #8
I think the problem might be is when you said that you swapped the 3.08s. I thought the 99+ GTs had 3.27s The speedometer is sensitive from what size gears you swapped to the new ones, seeing the Dallas mustang calibrator install.
 
T

tradde

New Member
Aug 2, 2005
94
0
0
Pennsylvania
Aug 5, 2005
#9
  • Aug 5, 2005
  • #9
Green&GoldGT said:
I think the problem might be is when you said that you swapped the 3.08s. I thought the 99+ GTs had 3.27s The speedometer is sensitive from what size gears you swapped to the new ones, seeing the Dallas mustang calibrator install.
Click to expand...

I am pretty sure they were 3.08s. I thought only Cobra's came with 3.27s?

The Predator should be here in a few days to fix the problem. It's so hot here
it's not even fun driving a vert with the top down.
 

V_Eight

Founding Member
Sep 5, 2002
617
1
0
ATL
Aug 5, 2005
#10
  • Aug 5, 2005
  • #10
Does someone make something mechanical I can swap out with the gauge cluster to make it read properly with my 3.73's?
 
C

CdnNavybob

New Member
Nov 24, 2003
105
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0
Aug 5, 2005
#11
  • Aug 5, 2005
  • #11
V_Eight said:
Does someone make something mechanical I can swap out with the gauge cluster to make it read properly with my 3.73's?
Click to expand...

No. As far as I know, the last mechanical piece in the system is the rpm sensor , which if I'm not mistaken is when the Dallas Mustang Speedcal hooks up. It's in the vicinity of the shifter. Everything from there up is all electronic. I had a DM Speedcal for a few weeks but it was defective. I exchanged it for the Predator, which I then realized I should have gooten in the first place. It would have saved me money on my MIL's as well.
 

Give Me TP

Member
Jun 17, 2004
936
0
16
Republic of Texas
Aug 5, 2005
#12
  • Aug 5, 2005
  • #12
tradde said:
I am pretty sure they were 3.08s. I thought only Cobra's came with 3.27s?

The Predator should be here in a few days to fix the problem. It's so hot here
it's not even fun driving a vert with the top down.
Click to expand...

The stock gears were 3.27, and if the shop that did the gear change still has your old ones you can count the teeth on the ring & pinion to confirm that. On the Predator you will simply select your current gear ratio, and the former stock ratio will make no difference. I am surprised that the HyperTech tuner didn't adjust the speedo properly though.
 
T

tradde

New Member
Aug 2, 2005
94
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0
Pennsylvania
Aug 5, 2005
#13
  • Aug 5, 2005
  • #13
Give Me TP said:
The stock gears were 3.27, and if the shop that did the gear change still has your old ones you can count the teeth on the ring & pinion to confirm that. On the Predator you wll simply select your current gear ratio, and the former stock ratio will make no difference. I am surprised that the HyperTech tuner didn't adjust the speedo properly though.
Click to expand...

I too was surprised at that. I just figured he did something wrong. We were outside in the sun so he could have read something wrong and not programmed
the gear change. He also mentioned he was not familiar with the Hypertech.
So I did it myself, and saw that it had indeed been set to 4.10s during the final
display. But for some reason it did not fix the problem. I don't see that it matters
what my old gears were like you said. With my luck the same problem will happen
with the Predator and I will discover it's some other goofy problem.
 

Ryan's 02 GT

New Member
Jul 26, 2004
100
0
0
Fayetteville, NC
Aug 5, 2005
#14
  • Aug 5, 2005
  • #14
The Predator was very easy to change ratios with. I'm suprised the Hypertech didn't work. Maybe the mech is not up on the programmers. Call Hypertech and maybe they can help. Remember to install the stock settings with the Hypertech before you plug in the Predator. Had a buddy who didn't and was stuck a few hours trying to figure it out. Good luck
 

forpit2000gt

Founding Member
Jun 30, 2002
2,490
0
0
Columbia, SC
Aug 5, 2005
#15
  • Aug 5, 2005
  • #15
the programmer has to know whtat the stock ratio is and then the new. You had 3.27s , not 3.08s.
 
T

tradde

New Member
Aug 2, 2005
94
0
0
Pennsylvania
Aug 5, 2005
#16
  • Aug 5, 2005
  • #16
forpit2000gt said:
the programmer has to know whtat the stock ratio is and then the new. You had 3.27s , not 3.08s.
Click to expand...

The Hypertech Programmer only asks the gear ratio being changed to. It does
not ask about what the old ratio was. That should have been whatever the
programmer was set up for stock. But weren't some Mustangs 3.08s? This
programmer covers many years of Mustangs. It cover 1999 and up 4.6L Mustangs
and Cobras. Is 3.27 stock in all of those? If so wouldn't the progammer be set
for that as stock?

How does the Predator change the ratio? Does it ask both?
 

Give Me TP

Member
Jun 17, 2004
936
0
16
Republic of Texas
Aug 5, 2005
#17
  • Aug 5, 2005
  • #17
No. The stock ratio according to your ECU will appear when you go to modify it, but does not have to be entered in any way. BTW the Predator will show 4.09 as a selection rather than 4.10, don't know why.

3.27s are stock in all '99+ Mustangs except '03-'04 Mach 1s and (I presume) Cobras which have 3.55s
 

forpit2000gt

Founding Member
Jun 30, 2002
2,490
0
0
Columbia, SC
Aug 6, 2005
#18
  • Aug 6, 2005
  • #18
I haven't used a hypertech, I received bad info from a friend, sorry. I used a speedcal for mine and no problems. All 99+ are 3.27 except 03 SC had 3.55.
 
T

tradde

New Member
Aug 2, 2005
94
0
0
Pennsylvania
Aug 6, 2005
#19
  • Aug 6, 2005
  • #19
forpit2000gt said:
I haven't used a hypertech, I received bad info from a friend, sorry. I used a speedcal for mine and no problems. All 99+ are 3.27 except 03 SC had 3.55.
Click to expand...

I see that now that stock is 3.27. For some reason I thought I had read stock
was 3.08. So I swapped from 3.27s to 4.10s. The Hypertech does not display
the current ratio. It only asked you to select from a scrollable list the ratio
changing to. I can't wait for the Predator to arrive. I am hoping today, but would guess Monday.
 
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