Home page

Speedo Circuit Board

Forum: C3 Electrical, Body and Interior

8 Messages
Page 1 of 1
Share:
Sponsored Content

Already a Member?

Welcome back! Access your account.

Sign In

Not yet a Member?

Join our community! Registration is free.

Join Free

Speedo Circuit Board

Posted: 9/7/06 8:46amMessage 1 of 8
8
Former Member
Send PM
Edmonton, Canada
Joined: 10/2/2005
Posts: 164
Vette(s): 1980 Black on Red with 383 Stoker 4 speed. T-Tops

Good day all, I have a question regarding the circuit board on the Speedo/Tach. I did search the forums and found a couple of topics but no answers. I wish to replace the speedo with a 140MPH and currently have the Canadian version of the 80MPH/140KPH, my question is are the circuit boards the same or are the Canadian boards calibrated to the KPH that we use?

Thanks in advance

T

80STROKER38967.3659027778
Be the first to like this post
Sign In to Like this post
SPONSOR AD:: (Our Sponsors help support Vette Registry)

Speedo Circuit Board

Posted: 9/7/06 8:59amMessage 2 of 8
Profile Pic
Lifetime Member
Moderator
Send PM
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 22720
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
I think the difference in the(fact.) kpm/mph speedos is just the printing on the face, and possibly the speedo gears themselves? Not really sure...
If you change to a higher range speedo, there may be a different board required, or maybe just a different resitor/shunt in the system.
If you have a supplier for the new speedo, you might need to ask if there are other mods/parts needed.

Joel Adams
C3VR Lifetime Member #56    

My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/7/06 6:52pmMessage 3 of 8
Profile Pic
Lifetime Member
Moderator
Send PM
CUYAHOGA FALLS, OH - USA
Joined: 12/2/2003
Posts: 6424
Vette(s): 1975 C3 Red, T-Tops, Black Interior. All I need is time and money! Getting there!

In a 1980?  Look close.   The speed is still cable driven.  The printed circuit board should not have any affect on the speed reading.  The difference is the calibration of the speedo head ( mechanical ) and the different face.

Some California speedos have a VSS, vehicle speed sensor, and all 81 have  the VSS as part of the speedo assy.  So the head is different but the calibration is still mechanical.

Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/7/06 7:04pmMessage 4 of 8
Profile Pic
Lifetime Member
Moderator
Send PM
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 22720
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
Wow!! Good catch on that one, Ken!

Joel Adams
C3VR Lifetime Member #56    

My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/8/06 12:21pmMessage 5 of 8
Profile Pic
Free Member
Send PM
Frederick, MD - USA
Joined: 9/8/2003
Posts: 3398
Vette(s): 1969 convertible L71 427/435 4-speed black interior
My '78 came with a metric speedometer. I swapped it out with a 140 mph speedo head and used the same printed circuit...no problem at all. I do think the speedometer reads a bit higher than is accurate, but not a lot. The tires are one size undersized (P245/60R-15 instead of P255/60R-15)), which may account for that. The tires were new on the car when I purchased it so I'm not going to spend for a new set just because of that.
Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/9/06 9:09amMessage 6 of 8
8
Former Member
Send PM
Edmonton, Canada
Joined: 10/2/2005
Posts: 164
Vette(s): 1980 Black on Red with 383 Stoker 4 speed. T-Tops

Thanks a bunch guys for the info. Much Appreciated  

T

Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/9/06 9:18pmMessage 7 of 8
Profile Pic
Lifetime Member
Moderator
Send PM
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 22720
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
[QUOTE=kstyer]

In a 1980?  Look close.   The speed is still cable driven.  The printed circuit board should not have any affect on the speed reading.  The difference is the calibration of the speedo head ( mechanical ) and the different face.


Some California speedos have a VSS, vehicle speed sensor, and all 81 have  the VSS as part of the speedo assy.  So the head is different but the calibration is still mechanical.

[/QUOTE]

Therefore, if you install a "normal"(not metrical) speedo head, it should be properly calibrated...

The 81-82's had 'lectrical speedos for the lock-up convertor to work. It needs a valid speed signal. The Calli cars got the 350lu in '79 or 80.

Joel Adams
C3VR Lifetime Member #56    

My Link


(click for Texas-sized view!)
             NCRS

"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

Be the first to like this post
Sign In to Like this post

Speedo Circuit Board

Posted: 9/10/06 7:00amMessage 8 of 8
8
Former Member
Send PM
Edmonton, Canada
Joined: 10/2/2005
Posts: 164
Vette(s): 1980 Black on Red with 383 Stoker 4 speed. T-Tops

Thanks guys, you da bomb   

T

Be the first to like this post
Sign In to Like this post
Share:

in Forum: C3 Electrical, Body and Interior


Sponsored Content