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70LonghornCST · 05-01-2009, 03:35 AM

I recently installed an American Auto Wire engine compartment harness. I then talked, by chance, to a tech that helped design the harness, and he said that I will need to run an inline tach filter if using the factory tach in order to get the proper RPM readings since I am using an HEI distributor. Has anyone who has installed the American Auto Wire harness come across this problem. I have not yet installed the new cluster with the tach into my truck so I am not sure what reading I will get. What do you think? I'd hate to be hasty and run out to purchase a tach filter only to find out that I did not need it.

05-01-2009, 03:35 AM	#1
70LonghornCST Moderator Join Date: Jun 2008 Location: Modesto, CA Posts: 5,775	Tach Question I recently installed an American Auto Wire engine compartment harness. I then talked, by chance, to a tech that helped design the harness, and he said that I will need to run an inline tach filter if using the factory tach in order to get the proper RPM readings since I am using an HEI distributor. Has anyone who has installed the American Auto Wire harness come across this problem. I have not yet installed the new cluster with the tach into my truck so I am not sure what reading I will get. What do you think? I'd hate to be hasty and run out to purchase a tach filter only to find out that I did not need it. __________________ 2018 Chevy Crew Cab 2006 Impala SS 1965 Plymouth Sport Fury 1970 Chevy Longhorn Bucket Seats Shoulder Belts Front Tow Hooks Factory Air Factory Speedwarning, Tach & Vaccum Factory Tilt CST Package AM/FM Radio Bumper Guards Richard 70 Longhorn CST Build Adding an AM/FM Decal Last edited by 70LonghornCST; 05-01-2009 at 03:37 AM.