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SN78SM

SKU: SN78SM

Mag Proximity Sensor (Senses ferrous targets to generate a sine wave signal for speedometers/May also require SN74)
$91.00

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.

Tachometer Filter Our Tach Filter is supplied with most Classic Tachometers. Installed between the Tachometer and the Ignition Trigger Source (usually the coil) this filter traps, redirects, and dissipates the high voltage spikes and surges that are emitted by any late-model high-energy ignition system. 

It also modifies the sharp up-and-down spikes into a semi-square wave signal for steady pointer readings and faster pointer response. Three color-coded wires allow for fast and easy fool-proof connections for life-time protection and superior response on all Classic Tachometers.

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.

Tachometer Filter Our Tach Filter is supplied with most Classic Tachometers. Installed between the Tachometer and the Ignition Trigger Source (usually the coil) this filter traps, redirects, and dissipates the high voltage spikes and surges that are emitted by any late-model high-energy ignition system. 

It also modifies the sharp up-and-down spikes into a semi-square wave signal for steady pointer readings and faster pointer response. Three color-coded wires allow for fast and easy fool-proof connections for life-time protection and superior response on all Classic Tachometers.

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