Product images and videos are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Ignitions and Electrical› Wiring Components
CLASSIC INSTRUMENTS
MAG PROXIMITY SENSOR
SKU: C05G SN78SM
Beginner — under 30 min
Overview
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Part #: SN78SM
The Magnetic Proximity Sensor will respond to pulse signals across a 1/16" air-gap between the sensor tip and disk-rotor, IRS-CV joint bolt-heads or notched brake-drum edge.;
It is useful on trans-axle setups or transmissions without mechanical speedometer cable connection.;
Using a stock GM Speed Sensor - 700R, 4L60, etc. Our Speed Pulse Convertor Box is used on late model GM 700-R or 4L60 over-drive transmission applications with a GM VSS (Vehicle Speed Sensor). This Convertor Box will convert the signals from the stock GM-VSS so your Classic Programmable Speedometer will read and operate correctly. The original GM-VSS signal can still be used to operate your fuel-injection, engine monitoring, transmission shift points, etc.
Magnetic Proximity Sensor
Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.
Fitment
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Specifications
| Brand | CLASSIC INSTRUMENTS |
| Part Number | C05G SN78SM |
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Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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