-7%

Classic Instruments SN20 Tach Filter Module

-7%

Classic Instruments SN20 Tach Filter Module
Classic Instruments

|

#2752005

Classic Instruments SN20 Tach Filter Module

  • Tachometer signal filter module for clean RPM readings
  • Eliminates electrical noise from ignition systems
  • Easy installation improving gauge accuracy
See More

$37.19

/each

In Stock

$40.23

Save $3.04


Quantity

Need Help? Call to Order

Add to a list

Share

Select a vehicle to verify Fitment

Select Vehicle

Product Summary

Universal Fit, .62" Overall Diameter

  • Tachometer signal filter module for clean RPM readings
  • Eliminates electrical noise from ignition systems
  • Easy installation improving gauge accuracy
  • Compatible with most Classic Instruments tachometers
  • Essential for reliable tachometer operation
See more details

Key Specs

MFG. Part #SN20
BrandClassic Instruments
See more specs

Need To Know

Need help?

855.313.9176
View the Help Center

Quick and Easy Returns

Return Policy

Classic Instruments SN20 Details

Eliminate unwanted electrical interference and ensure accurate tachometer operation with the Classic Instruments SN20 Tach Filter Module. Designed to clean up RPM signals affected by ignition system noise, this compact module helps deliver stable and reliable tachometer readings in performance vehicles, hot rods, muscle cars, classics, and custom builds. Easy to install and highly effective, the SN20 improves gauge accuracy by filtering out signal disruptions that can cause erratic needle movement or inaccurate RPM displays. Compatible with most Classic Instruments tachometers, it's an essential component for enthusiasts demanding precise engine monitoring.

  • Tachometer signal filter module for clean and accurate RPM readings
  • Eliminates ignition system electrical noise and interference
  • Improves tachometer stability and gauge accuracy
  • Easy installation for restoration, performance, and custom vehicle applications
  • Compatible with most Classic Instruments tachometers
  • Essential for reliable tachometer performance in modern and classic ignition systems

Charts

Classic Instruments SN20 Specifications

KEY SPECS
MFG. Part #SN20
BrandClassic Instruments
GENERAL
Overall Diameter.62"
Sold in QuantityEach
NotesWire length is 9.00"

Ratings & Reviews

4.7

16 Reviews

Overall Assessment

Customers widely praise the product for effectively eliminating erratic movement on tachometers and speedometers, enhancing accuracy. Users underline its easiness of installation, practicality, and usefulness. The product's excellent quality material contributes to its overall robustness and resilience. Multiple customers specifically state it as being the optimal solution when compared to other brands, emphasizing its superiority in stabilizing meter readings. Despite one case where it was ineffective on a specific model, the majority confirm the product as an ideal, reliable fix for bouncing gauges.

Write A Review

4.7

16 reviews

5

14

4

1

3

0

2

0

1

1

Most Liked Positive Review

4.0

Stop the jitters

I installed at the most obvious location, in my case, directly into the HEI distributor tach terminal and then was concerned about the elements and engine heat. Probably should have tied into the tach feed under the dash for more protection.

Most Liked Negative Review

1.0

Does not work.

Does not solve eratic needle bounce on 68 chev tic-toc-tach (after switch from points to elect distributor.)

Filter by Ratings

Very compact

5.0

7 months ago

FLD

Grand junction co

Verified

Small enough to install anywhere, easy to connect

Would Recommend

If you have an erratic tachometer or speedometer this is it!

5.0

3 years ago

L

Pa

Verified

It stopped my tach jumping around. I thought it helped my speedometer but just the tachometer. If you have a digital dash and the speedometer bounces around then it is most likely your coil! Took out my new hi performance coil and replaced it with the stock and all is good now!

Would Recommend

This filter stopped the jumping needle on my tachometer.

5.0

4 years ago

BIG-O-EXPRESS

Willoughby ohio

Verified

My needle on my tachometer was jumping around. I installed this filter and it solved the problem. Great product

Would Recommend

I would buy this product again

5.0

5 years ago

Drew

Vincent, OH

Verified

I bought this device to keep my gauges from bouncing around. It made it so I could get an actual reading from the gauge.

Would Recommend

Tach filter

5.0

6 years ago

mick

Springfield ,Ill

Verified

Easy to install, works great .Satisfied with my purchase

Would Recommend

Yes

5.0

7 years ago

Ford

Edmond

Verified

Great price.

Would Recommend

Worked great on vdo tach

5.0

7 years ago

Minty Fresh

Ontario Ca

Verified

This noise filter took all the bounce out of my tach . Installed behind the dash , tach gives solid reading at needle now

Would Recommend

Ignition upgrade must

5.0

8 years ago

C10 u Later

Texas

Verified

Great quality part with clear directions. Nice heavy gauge wires with plenty of excess.

Would Recommend

Works Like A Charm !!

5.0

8 years ago

WIJr

Baytown, TX

Verified

My Classic Instruments 4 5/8" tach was very erratic and read about 700-800 RPM high. I ordered the SN20 filter based on their tech support suggestion. I got the filter installed this evening in my 64 El Camino.and the problem is solved. Very stable readings now.

Would Recommend

Best filter

5.0

9 years ago

GW

Sebastian Fl

Verified

Tried all ways to stop eradic tach needle. This one works great. Used it on VDO.

Load More Reviews

Showing 10 of 16 reviews

Questions & Answers

6 Questions • 6 Answers

Will this work with an ls1 engine using aftermarket tach gauge

by Ls swap monte carlo

• 3 years ago

1 answer

View Answer

will the sn20 tach filter work with 1967-1972 chevy pickups with aftermarket tach kits thank you ed blinzler

by ed

• 9 years ago

1 answer

View Answer

Will this filter work on a 6V system, positive ground system with a dual point Mallory distributor and a Flamethrower coil? If so, how should it be wired?

by Jim

• 10 years ago

1 answer

View Answer

Will this tach filter work on Chevy HEI distributor and what wires go where. Please include in answer the wiring to a 1980 Corvette OEM HEI distributor. Thank you, Sal C

by Sammy80

• 11 years ago

1 answer

View Answer

Will this work with a points ignition? I'm trying to replace the tach filter on my 73 Camaro that has the original points ignition.

by Lou1

• 12 years ago

1 answer

View Answer

I need to know which wire goes where?

by rattrod

• 15 years ago

1 answer

View Answer

6 of 6 questions shown

Customer Impersonation Script