Spark Plug Wires, Over or Under Headers?
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
Spark Plug Wires, Over or Under Headers?
Looking for opinions regarding best routing and appearance. I have always gone over the headers but looms seems to never work quite right and the wires seem very close to the tubes. I am going with 1 7/8" primary tube headers so I will even be harder now. I am leaning toward going under this time. Thoughts?
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
I just went over. All wires are 1 1/2 minimum from 1 7/8 tubes.
https://www.corvetteforum.com/forums...post1589183171
https://www.corvetteforum.com/forums...post1589183171
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
I've never tried the aftermarket under header wire setups. Although on my new engine I purchased some pre-made "Live Wires" from Davis Unified Ignition.. They route under the headers. I trial fit them on my new engine while on the engine stand. They fit great and lots of header clearance. I think the clean look will be a nice addition to the engine compartment.
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
I just went over. All wires are 1 1/2 minimum from 1 7/8 tubes.
https://www.corvetteforum.com/forums...post1589183171
https://www.corvetteforum.com/forums...post1589183171
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
I've never tried the aftermarket under header wire setups. Although on my new engine I purchased some pre-made "Live Wires" from Davis Unified Ignition.. They route under the headers. I trial fit them on my new engine while on the engine stand. They fit great and lots of header clearance. I think the clean look will be a nice addition to the engine compartment.
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Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
Thread Starter
Melting Slicks
Joined: Nov 2000
Posts: 2,738
Likes: 53
From: Bogart GA
Looking for opinions regarding best routing and appearance. I have always gone over the headers but looms seems to never work quite right and the wires seem very close to the tubes. I am going with 1 7/8" primary tube headers so I will even be harder now. I am leaning toward going under this time. Thoughts?
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
The nice thing about over the top with the looms is when you pull the distributor or just the cap you can pull the plug wire boots off the plugs and remove 4 valve cover bolts and the whole works comes off in one piece. When reinstalling the wires are already laid out front to back in the looms. No chance of mixing anything up like 5&7 (EASILY DONE) been there, screwed that up. 
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
When reinstalling the wires are already laid out front to back in the looms. No chance of mixing anything up like 5&7 (EASILY DONE) been there, screwed that up.
I number my wires with a sharpie. It's all under the chrome static shield anyhow and invisible.
Le Mans Master
Joined: Apr 2006
Posts: 5,403
Likes: 95
Have never liked the looks of spark plug wires or big distributors like an HEI. Always put the wires down the back of the block and under the headers. One of the nice things about the latest modern engines ugly plug wires and dist. are gone.
Last edited by Little Mouse; Mar 29, 2015 at 08:14 PM.
Racer
Joined: Sep 2013
Posts: 361
Likes: 6
From: Jamestown Ohio
I've never tried the aftermarket under header wire setups. Although on my new engine I purchased some pre-made "Live Wires" from Davis Unified Ignition.. They route under the headers. I trial fit them on my new engine while on the engine stand. They fit great and lots of header clearance. I think the clean look will be a nice addition to the engine compartment.
I'm needing some under header looms for my 454.. any ideas?