Spark Plug Wires By Length
Thread Starter
Racer
Joined: Jul 2008
Posts: 446
Likes: 1
From: Cary NC
Spark Plug Wires By Length
Hello,
When i bought my car the spark plug wires were all mixed up (some were so tight against headers and others very loose). I was wondering if anyone has a diagram to tell which length wire goes to which spark plug. I am routing them under my headers. I've tried 5 different configurations but none seem right, this is becoming more frustrating that the heater core
.
Thanks,
Michal
When i bought my car the spark plug wires were all mixed up (some were so tight against headers and others very loose). I was wondering if anyone has a diagram to tell which length wire goes to which spark plug. I am routing them under my headers. I've tried 5 different configurations but none seem right, this is becoming more frustrating that the heater core
.Thanks,
Michal
Intermediate
Joined: Nov 2009
Posts: 35
Likes: 0
From: Lancaster SC
Spark Plug Wire Length
Hey Michal,
What year and what engine are you running. Mine is a 76 with the L-48 350 and stock exaust manifolds. I have the original wires I just removed and a replacement set I haven't put on yet. The original routing is for the #'s 1 & 3 on the left and the #'s 2 & 4 on the right to run down into heat shields (l & r) that go from the back of the motor, down to the lip of the oil pan and then up to the motor mounts. The wires exit the shields, go thru the mounts and go to the plugs. If you need exact measurements, let me know and I'll get them to you but with you running headers I don't know if it's going to help. You might have to make a set to get them to fit correctly.
Jimmy
What year and what engine are you running. Mine is a 76 with the L-48 350 and stock exaust manifolds. I have the original wires I just removed and a replacement set I haven't put on yet. The original routing is for the #'s 1 & 3 on the left and the #'s 2 & 4 on the right to run down into heat shields (l & r) that go from the back of the motor, down to the lip of the oil pan and then up to the motor mounts. The wires exit the shields, go thru the mounts and go to the plugs. If you need exact measurements, let me know and I'll get them to you but with you running headers I don't know if it's going to help. You might have to make a set to get them to fit correctly.
Jimmy
Drifting
Joined: Apr 2008
Posts: 1,305
Likes: 2
From: Lewisburg WV
thgazman
Jimmy...Obviously the longest wires go to the plugs the farthest from the distributor, etc., etc. The easiest way to install plug wires on a C-3 is to buy a good quality universal set where you install the distributor terminals on after cutting the wire to length. Universal wires makes it easier to install the wires at the front of the engine under the motor mounts.
Le Mans Master
Joined: Mar 2001
Posts: 6,640
Likes: 287
From: Ann Arbor Michigan
This is the correct lengths for a 71-74 (prior to HEI dizzy). Not sure what year you have but if you have HEI, I would guess all the wires are an inch or 2 longer but the length relationship should be the same (Longest wires are 1,2 and 3 etc)
Gary
Gary
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,114
From: Crossville TN
Since the distributor is offset from engine center by a few inches to the right side, the ordered sequence of wiring lengths [longest to shortest] are in cylinder order: #1, #2, #3, #4, #5, #6, #7, #8. Some will be the same actual length; but the ordering will stay the same. {Should be true, regardless of SB or BB...HEI or points.}
Intermediate
Joined: Nov 2009
Posts: 35
Likes: 0
From: Lancaster SC
Looked at the sheet that came with the new wires and the lengths listed are as follows ( I'd scan it but the scanner is on the fritz ):
1975 -77 Corvette - All
Wire #1 - 46" Wire #2 - 54"
Wire #3 - 54" Wire #4 - 42"
Wire #5 - 28" Wire #6 - 28"
Wire #7 - 22" Wire #8 - 26"
Wires #'s 2 & 3 are longer because they have to cross over each other in front of the dist. and go to the opposite sides of the engine, as the others go to the sides that they're on the dist. Don't know if these measurements are correct for my car because my engine is still appart but I have a feeling the #7 should be the 26" and the #8 should be the 22" because of what 7T1vette said about the dist. being offset th the right side. Hope this helps.
1975 -77 Corvette - All
Wire #1 - 46" Wire #2 - 54"
Wire #3 - 54" Wire #4 - 42"
Wire #5 - 28" Wire #6 - 28"
Wire #7 - 22" Wire #8 - 26"
Wires #'s 2 & 3 are longer because they have to cross over each other in front of the dist. and go to the opposite sides of the engine, as the others go to the sides that they're on the dist. Don't know if these measurements are correct for my car because my engine is still appart but I have a feeling the #7 should be the 26" and the #8 should be the 22" because of what 7T1vette said about the dist. being offset th the right side. Hope this helps.
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