145mph speedo
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Car: 86 SC
Engine: 5.0 305 LG4
Transmission: M5
Axle/Gears: 3.23
145mph speedo
Is it possible to replace just the speedometer in the gauge cluster, and keep everything else?
I want to change in my 85 mph'er
I want to change in my 85 mph'er
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Car: 1988 IROC-Z
Engine: Fast Burn 385 Crate Engine / Accel DFI
Transmission: T-56
Axle/Gears: 10 Bolt Auburn Pro / 4.10 Gears
185 to 240 speedo
I just changed mine from the 185 speed to the 240 speedo. The only difference is the actual face plate. I guess you just have to change your tranny speedo gear to recalibrate to the proper speed. as the internals of the speedo are identical, I believe the speedo cable is what is responsible for the difference in speed. I haven't used the car yet but I'm also changing to a 3.73 gear. so I'll need a speedo tranny gear for a 240 speedo and 3.73 gear.
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Car: 86 SC
Engine: 5.0 305 LG4
Transmission: M5
Axle/Gears: 3.23
So all I have to do is get a new faceplate for the 145mph(???kph), and a tranny speedo gear for a 145 with 3.23 gears.
great, where do you think I can find a tranny speedo gear for that combo?
tuff to install??
great, where do you think I can find a tranny speedo gear for that combo?
tuff to install??
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Car: 87 IROC-Z28
Engine: 305 TPI-New 355 on the engine stand
Transmission: T56
Axle/Gears: 3.73 Eaton posi-Soon a 9" Ford!
I was just at my local speedometer shop and asked the guy about changing only the gears to get a 85mph speedo to read correctly with a 145mph face. Basically, it can't be done with the gearing in the trans. You have to replace or possibly find a way modify the existing 85mph speedometer head to read correctly with the 145 face plate.
If you are changing rear end ratios and have an electric speedo with a VSS unit, there are two kinds of setups for these. One uses the standard speedometer gears in the trans to drive the VSS unit, and the other uses a relucter ring and a magnetic pickup.
To make the gear driven one read correctly with a different rear end ratio, you simple change out the gears to drive the VSS at the proper speed.
On the relucter pickup style, you have to by a new VSS from a dealer that gives you the proper pulse counts to make your speedo read correctly. You need to tell the dealer what yor tire size is, and what rear end ratio you have, then he can supply you with the proper VSS unit for your car.
If you are changing rear end ratios and have an electric speedo with a VSS unit, there are two kinds of setups for these. One uses the standard speedometer gears in the trans to drive the VSS unit, and the other uses a relucter ring and a magnetic pickup.
To make the gear driven one read correctly with a different rear end ratio, you simple change out the gears to drive the VSS at the proper speed.
On the relucter pickup style, you have to by a new VSS from a dealer that gives you the proper pulse counts to make your speedo read correctly. You need to tell the dealer what yor tire size is, and what rear end ratio you have, then he can supply you with the proper VSS unit for your car.
Last edited by alloy; 04-01-2003 at 03:41 PM.
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Car: 87 Formula T-Top, 87 Formula HT
Engine: 5.1L TPI, 5.0L TPI
Transmission: 700R4, M5
Axle/Gears: Sag 3.73, B&W 3.45
First IF you are JUST changing the Speedo and not the gears etc, then all you need to change is the Speedo Assembly, not just the faceplate.
SECOND, If you replace jsut the faceplate and recalibrate the transmission to the speedo, the Odometer will be off therefore (ILLEGAL)
THIRD, Its TONS easier to just change the Speedo out to a 145 Model whether or not you have a cable drive or an electonic speedo period, anyone who likes to crawl uder their car get driped on by your trans as you remove the tailcone, drop the driveshaft, is nuts...
My advise, find out what years will fit, I think in the Camaro 82-89 are interchangable but ask here they should know, I am a Firebird guy, I deal with electonic speedos...
John
SECOND, If you replace jsut the faceplate and recalibrate the transmission to the speedo, the Odometer will be off therefore (ILLEGAL)
THIRD, Its TONS easier to just change the Speedo out to a 145 Model whether or not you have a cable drive or an electonic speedo period, anyone who likes to crawl uder their car get driped on by your trans as you remove the tailcone, drop the driveshaft, is nuts...
My advise, find out what years will fit, I think in the Camaro 82-89 are interchangable but ask here they should know, I am a Firebird guy, I deal with electonic speedos...
John
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Car: '86 IROC
Engine: 305 LG4 awaiting the crate Vortec 350
Transmission: 700R4
someone wanna tell me whats going on with all this HITHERE bullHITHEREHITHEREHITHEREHITHERE? Is there HITHERE virus in the system or something and why is everyone in the "administration"?
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Car: 1987 Z28
Engine: 383 Single Plane EFI-NOW RUNNING!
Transmission: T56
Axle/Gears: Not there yet...
[HITHERE]Originally posted by Need4Speed1387 [/HITHERE]
someone wanna tell me whats going on with all this HITHERE bullHITHEREHITHEREHITHEREHITHERE? Is there HITHERE virus in the system or something and why is everyone in the "administration"?
someone wanna tell me whats going on with all this HITHERE bullHITHEREHITHEREHITHEREHITHERE? Is there HITHERE virus in the system or something and why is everyone in the "administration"?
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Get on the clue bus!!!!!!!!
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