dist cap [message #327275] |
Tue, 19 December 2017 07:23 |
palerider
Messages: 35 Registered: September 2013 Location: Kingsland , Texas
Karma: 1
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Hey guys, newbie back with more questions. Somewhere a few days ago in a galaxy far far away (usually where my head is) I saw a pic of a GMC on one of the sites with a stock type HEI looking cap with an external coil post. Supposedly an MSD unit but danged if I can find it again. The guy even had a part number for it. He said he had no coil problems after changing to it and removing the coil from the engine heat. Anyone know what it is...Thanks.....Tom
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Re: dist cap [message #327278 is a reply to message #327275] |
Tue, 19 December 2017 08:09 |
Carl S.
Messages: 4186 Registered: January 2009 Location: Tucson, AZ.
Karma: 13
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palerider wrote on Tue, 19 December 2017 06:23Hey guys, newbie back with more questions. Somewhere a few days ago in a galaxy far far away (usually where my head is) I saw a pic of a GMC on one of the sites with a stock type HEI looking cap with an external coil post. Supposedly an MSD unit but danged if I can find it again. The guy even had a part number for it. He said he had no coil problems after changing to it and removing the coil from the engine heat. Anyone know what it is...Thanks.....Tom
You should find what you need here:
http://www.gmcmhphotos.com/photos/general-pictures/p63438-msd-coil-conversion.html
Carl Stouffer
'75 ex Palm Beach
Tucson, AZ.
Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
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Re: dist cap [message #327285 is a reply to message #327275] |
Tue, 19 December 2017 09:50 |
Chris Tyler
Messages: 458 Registered: September 2013 Location: Odessa FL
Karma: 7
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Its an MSD 8401. You will also need a high tension lead of sufficient length and a good coil like the MSD Blaster
To he honest, for our applications iits a bit of overkill UNLESS you ad the MDS CD box or the equivalent.
Also, most failures I have had with HEIs its the module at fault. Only once have I had a pickup fail. If you go tho the MSD box you can leliminate it or keep the working module in place in case it fails
76 Glenbrook
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Re: dist cap [message #327291 is a reply to message #327275] |
Tue, 19 December 2017 10:40 |
JohnL455
Messages: 4447 Registered: October 2006 Location: Woodstock, IL
Karma: 12
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Adding external coil adds failure point. The lead between the coil and cap gets taxed with all the pulses not one in eight like cylinder wires. My 97 Tahoe has that setup factory and that lead burnt off at the cap shortly after it was new to me vehicle. End of wire was gone but hidden by boot. In the rain. In an intersection. Cost me a tow home to where I could diagnose. I can only imagine what they would have charged me if it was towed to a shop with "computer diagnostic fees" and parts I did not need.
John Lebetski
Woodstock, IL
77 Eleganza II
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Re: dist cap [message #327292 is a reply to message #327275] |
Tue, 19 December 2017 10:46 |
JohnL455
Messages: 4447 Registered: October 2006 Location: Woodstock, IL
Karma: 12
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On the other hand I have been driving GM HEI coil in cap type since 1976 and never had a coil, module or pickup failure. You decide.
John Lebetski
Woodstock, IL
77 Eleganza II
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