----- Original Message -----
Sent: Friday, December 07, 2001 9:16
PM
Subject: Re: [Chevelle-List] Spark
plugs & Resistor wire.
The spark plugs recommended for a 1971
Chevelle is AC R45T with a gap of .035. The plug for a 1975 is R44T with a
gap of .060. The plug for a 1976 is R45T with a gap of .045. The plug for
a 1977 is R45T with a gap of .045.
My question is- being that I am using a HEI
dist. what should I set the gap at, .060 or .045 The second question
is should I go to a R44T plug.
My third question is should I look at a
better coil. I now have a stock HEI coil. Can you buy a High Perf. coil
which will fit inside the top to the stock HEI dist. cap??
Keith
----- Original Message -----
Sent: Friday, December 07, 2001
10:40 AM
Subject: Re: [Chevelle-List] Spark
plugs & Resistor wire.
You bring up a very good point. I have been
purchasing spark plugs are a 71 Chevelle, when I should be buying plugs
for a 1975 something. You have the book, but I thought that HEI where
put in 1972 cars. Thanks for the information. I really overlooked the
spark plugs application.
Keith
----- Original Message -----
Sent: Friday, December 07, 2001
10:38 AM
Subject: [Chevelle-List] Spark
plugs & Resistor wire.
Let me try and clear up some
confusion. First, I'm not an expert on this but I do have some
knowledge on the subject.
The HEI was was installed
across the GM car line in 1975 through 1980. After that computer
controlled HEI's came in. The main difference being the external
vacume advance housing. Conventional point dist. can only handle 2.5
amps before burning up. The HEI can handle 4 amps. More amps, better
coil saturation. Since the HEI needs a full 12 volts to run
efficiently (unlike points, 8 volts) you MUST lose the resistance
wire. The HEI can produce 35000 + volts but it needs the full 12 volts
to do this. (coil saturation) The resistor wire causes a voltage drop
after starting. During starting it is by-passed. This wire is what
kept the points from burning up. Keith is right about the PINK wire.
But don't make it too long. The longer the path, the less voltage. As
for spark plugs and the HEI, you should be sure to use the right
application. Plugs designed for conventional ignitions should
not be used because when you open the gap you are really bending the
electrode at an angle. To fire efficiently the ground electrode should
be flat over the center electrode. HEI plugs have a shorter center
electrode. And this allows for the larger gap. Larger gap, longer
spark. And don't over look the plug wires. You need at least 8mm wire.
Use a good silicone and wipe the inside of the plug and dist. boot. It
not only keeps moisture out but helps keep voltage loss down. Not to
mention easier boot removal. A very good book I bought several years
ago was "IGNITION / ELECTRICITY BOOK by Dr. Christopher Jacobs. It may
still be available. I think it cost around 15 bucks. Hope this small
bit of info helps everyone.
Rich
