Topic: 1979 tachometer with MSD 6AL
in Forum: C3 Electrical
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Baker, LA - USA
Joined: 12/12/2011
Posts: 9
Vette(s): 1979 Corvette, ZZ4 with serpentine belt front dress, ATI THM 350 with 3500 stall, Vette Brakes and Products suspension, tires - 295/50 rear 255/60 front on factory aluminum alloys, Autometer guages
My 79 ignition system is an MSD pro billet distributor with a 6AL box. I am hooked up from the Tach output on the 6AL to the tach wire under the dash. The tach filter went bye bye with the L48 engine. The tach moves but reads 3 or 4 times the accual RPM. Should I get a stock style tach filter, or the MSD tach adapt? (not the mechanical) Or is the output on the MSD "clean" enough that this is a symptom of a bad tach board?
Thanks
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Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
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#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
I would see if I could contact MSD, and see what they recommended. They may have a specific filter for you application...
Joel Adams
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Former Member
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Baker, LA - USA
Joined: 12/12/2011
Posts: 9
Vette(s): 1979 Corvette, ZZ4 with serpentine belt front dress, ATI THM 350 with 3500 stall, Vette Brakes and Products suspension, tires - 295/50 rear 255/60 front on factory aluminum alloys, Autometer guages
Sorted out the Tach / MSD 6al issue. It was the tach board. Not a big surprise. MSD output on the ignition box is compatible with the corvette tach with no mods.
Lifetime MemberHOWELL, NJ - USA
Joined: 5/18/2004
Posts: 6812
Vette(s): 1979, Targa Blue (72 Color), Pace Car rear spoiler, L88 hood, Dark blue factory interior, 525HP 406, HD 700R4, 370 gears,Steeroids, composite rear spring, TT IIs wrapped in T/A Radials.
I'm running the same set up on my 79, however, I am using the tach wire from the distributor plugged into the 6AL. Reads perfectly - also dumped the tach filter with no problems.
PM me if you'd like assistance.
Paul
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in Forum: C3 Electrical
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