FAQ |
Members List |
Social Groups |
Calendar |
Search |
Today's Posts |
|
#1
|
|||
|
|||
speed O against odometer
OK,probably simple.My speedometer in my 62 GP is 21% off.Will that mean my odometer is 21% off.I feel it should be.Tom
|
#2
|
||||
|
||||
Yes
__________________
1965 Pontiac LeMans. M21, 3.73 in a 12 bolt, Kauffman 461. |
#3
|
|||
|
|||
Thanks!Tom
|
#4
|
|||
|
|||
I’m not sure that’s necessarily true. It could be, though. The odometer is strictly a mechanical connection, so it is what it is, but the speedometer needle is driven magnetically, with no mechanical link, and the two wouldn’t have to match. Just my 2 cents.
__________________
Lee Peterson ------------- "I didn't expect a kind of Spanish Inquisition...!" '69 Cameo White RA III Judge, 4 speed, owned since 1977 -- my first car. |
The Following 2 Users Say Thank You to LPete For This Useful Post: | ||
#5
|
||||
|
||||
speedo is magnetically coupled and the needle reading fights a return spring. That copper spring could have corrosion and read high.
|
#6
|
|||
|
|||
I know the speedo is off because of a trans and rear end change.I have that handled just was wondering about the odometer.Tom
|
#7
|
||||
|
||||
With a trans and axle change everything will be off by the same amount. You can correct both by changing the speedometer gear in the transmission.
__________________
If you built it, drive it. red 62 Tempest total stock restoration. white 62 Tempest modified, 61 389 Tri-Power, and a conventional drive train. |
#8
|
|||
|
|||
The only way to correct my trans is to make a change on the internal gear on the main shaft.I have learned to live with it.Tom
|
#9
|
||||
|
||||
I think you can get an adapter to go between the cable and the tranny.
But otherwise just remember to change the mileage for MPG calculations by 21% up/down.
__________________
John Wallace - johnta1 Pontiac Power RULES !!! www.wallaceracing.com Winner of Top Class at Pontiac Nationals, 2004 Cordova Winner of Quick 16 At Ames 2004 Pontiac Tripower Nats KRE's MR-1 - 1st 5 second Pontiac block ever! "Every man has a right to his own opinion, but no man has a right to be wrong in his facts." "People demand freedom of speech to make up for the freedom of thought which they avoid." – Socrates |
#10
|
|||
|
|||
When I had 4.10s,L60 15s in my SD I got the external adapter. It worked. GM had at least 2 that I remember. I also changed the gear on the trans adapter to get the speedometer close. Since I put everything back to stk.
|
#11
|
|||
|
|||
Quote:
Back when I worked at a number ofPontiac dealers, we set up rearends with gearing changes, then took them to Speedometer Exchange. They repaired/ replaced speedometers when necessary and calibrated them with an adapter that was little more than a housing (which would fit in a large hand) with the appropriate gear sets to correct speedo. They used to do this for law enforcement also. |
#12
|
|||
|
|||
It happened when I put the 2.68 in the back.Tom
|
The Following User Says Thank You to tom s For This Useful Post: | ||
#13
|
|||
|
|||
Don't know how close you live to any major interstates, but on the sides of the interstate are mile markers. These can be used to confirm you odometer as being off or not. They are typically broken down in 1/10ths, so you can sorta get an idea how much the odometers is off. I have used this to gauge mine in the past and if you don't have a GPS/MPH app on your phone, 60 miles an hour is 1 mile a minute and with your watch you can figure if your speedo is off.
|
#14
|
||||
|
||||
Plenty of interstate access in SoCal, but I don't remember mile markers during my driving experience there in '05. The 5, the 101, etc.
|
#15
|
||||
|
||||
Easy enough to run with someone's, 'correct speedo' for 5 - 10 miles and check it.
If it is 21% off, 5 miles should give you approximately a mile difference right? Frank
__________________
Poncho Huggen, Gear Snatchen, Posi Piro. |
#16
|
||||
|
||||
2.68 ! You are ready to go cross country now!
|
#17
|
||||
|
||||
I have and use a Speedo app on my phone.
No guessing...
__________________
When I die, I want to go peacefully like my grandfather did, in his sleep. Not screaming like the passengers in his car. |
The Following User Says Thank You to Jeff Hamlin For This Useful Post: | ||
#18
|
|||
|
|||
Rather than changing the drive gear in my transmission,I bought this https://www.cpttransmission.com/.I called and told him the percentage is was off,and when it showed up it was dead on vs a GPS
|
#19
|
|||
|
|||
that site can not be found?I have the speedo diff down pat,im not sure about the odometer yet.I have a couple gps apps.Tom
|
#20
|
||||
|
||||
__________________
" Darksiders Rule "
|
Reply |
|
|