If you have American Racing Headers, CHECK THIS!

Jason18ZL1LE · 02-11-2019, 03:57 PM

So some of you may recall I have been dealing with a weird issue getting Stabilitrak and Fuel Pump A Voltage Low codes when making hard left turns on the track back in Nov. Since then the problem got progressively worse.

Well since then we found the issue (today actually) and we found that on the passenger side main fuse box harness (under the coolant tank) there is a harness that instead of being ran on TOP of the frame rail, it runs next to it between the frame and the manifold.

With ARH headers, the way the primaries are routed, the 1 7/8" headers will make contact with this harness under load and with the chassis twist under large G loads. 2" headers will nearly touch is sitting still.

What we ended up doing after we repaired the harness was reroute the harness on top of the rail (as GM should have) and the issue is resolved. I will be adding head protection wrap next.

My builder said he hasnt seen this issue with Kooks or SW headers due to their slightly different tube bends.

If you have ARH headers, this is worth a look. I never knew this was happening until I tracked the car or did hard canyon runs. The issue NEVER happened on the street. So you could have this issue and not even know it yet.

Can'tHave2MuchHP · 02-11-2019, 04:02 PM

Good post. Though I feel like the installer should thoroughly check for good clearance at all points so this probably "shouldn't" have happened...But sounds like this was a car-to-car issue that was a GM assembly error.

Jason18ZL1LE · 02-11-2019, 04:05 PM

You are correct, this could have been spotted however the installer hadn't been doing too many ARH systems due to the cost but I was insistent that we use ARH. Fortunately due to this he was able to go back to the ARH systems hes installed lately and revise them. He did say there is some variance in the slack on the harness. What actually happened is there is too much slack which caused it to bow out towards the header.

Consider this a learned experience.

2018ZL1 · 02-11-2019, 05:49 PM

I just installed the 2 inch ones on mine! I am gonna have to take a close look at this. I had mine ceramic coated so I wonder if that would make a difference???

Agent K · 02-11-2019, 06:03 PM

First, thanks for the heads up.

I recently installed a set of ceramic coated catless 1-7/8" ARH headers. My wire harness is ran on top of the firewall not on the side. Your installer took a different route than I did in installing the headers. I didn't have to touch that wire harness. I just checked just to make sure though...all good.

Jason18ZL1LE · 02-11-2019, 06:16 PM

Quote:

Originally Posted by Agent K

First, thanks for the heads up.

I recently installed a set of ceramic coated catless 1-7/8" ARH headers. My wire harness is ran on top of the firewall not on the side. Your installer took a different route than I did in installing the headers. I didn't have to touch that wire harness. I just checked just to make sure though...all good.

He had 3 different ZL1s that he checked and 2 (mine included) was making contact with the header.

What we found is an inconsistent routine of the harness between cars. Didn’t matter if it was an 18 or 19. I figured this would be a quick thing to check since some (like mine) was routed to the side instead of on top of the rail

Jason18ZL1LE · 02-11-2019, 06:17 PM

Also to be clear this harness is running from firewall to the front of the fuse box, not along the firewall. This is the factory location for the harness

sage85z28 · 04-18-2020, 04:06 PM

Quote:

Originally Posted by 2018ZL1

I just installed the 2 inch ones on mine! I am gonna have to take a close look at this. I had mine ceramic coated so I wonder if that would make a difference???

Who did you send them to for coating?

2018ZL1 · 04-18-2020, 04:10 PM

Quote:

Originally Posted by sage85z28

Who did you send them to for coating?

These folks, they are holding up really well so far.

https://mtairycoatings.com/

SJFGTO · 04-18-2020, 06:02 PM

Interesting. I have 2 inch ARH headers which were installed by Vengeance Racing. Not an issue at all on my ZLE. I agree with the above post that the install can head off this potential issue in advance.

XXX ZL1 · 04-18-2020, 11:27 PM

I wrapped mine in heat tap and zip ties with the push pins on the end to secure the harness to the frame rail. Tons of room now.

waterman · 04-19-2020, 03:55 PM

02-11-2019, 03:57 PM	#1
Jason18ZL1LE Drives: 2018 ZL1 1LE Join Date: Apr 2018 Location: SoCal Posts: 134	If you have American Racing Headers, CHECK THIS! So some of you may recall I have been dealing with a weird issue getting Stabilitrak and Fuel Pump A Voltage Low codes when making hard left turns on the track back in Nov. Since then the problem got progressively worse. Well since then we found the issue (today actually) and we found that on the passenger side main fuse box harness (under the coolant tank) there is a harness that instead of being ran on TOP of the frame rail, it runs next to it between the frame and the manifold. With ARH headers, the way the primaries are routed, the 1 7/8" headers will make contact with this harness under load and with the chassis twist under large G loads. 2" headers will nearly touch is sitting still. What we ended up doing after we repaired the harness was reroute the harness on top of the rail (as GM should have) and the issue is resolved. I will be adding head protection wrap next. My builder said he hasnt seen this issue with Kooks or SW headers due to their slightly different tube bends. If you have ARH headers, this is worth a look. I never knew this was happening until I tracked the car or did hard canyon runs. The issue NEVER happened on the street. So you could have this issue and not even know it yet. Attached Images

02-11-2019, 06:03 PM	#5
Agent K Drives: 2017 ZL1 6MT Join Date: Feb 2018 Location: Memphis, TN Posts: 190	First, thanks for the heads up. I recently installed a set of ceramic coated catless 1-7/8" ARH headers. My wire harness is ran on top of the firewall not on the side. Your installer took a different route than I did in installing the headers. I didn't have to touch that wire harness. I just checked just to make sure though...all good. __________________ 2017 ZL1 Arctic Blue Metallic / 6MT / sunroof / NAV / PDR / RotoFab CAI + dry filter / Tony Mamo TB V1 / Skip Shift Eliminator / Hurst Short Throw Shifter / ZL1 floor mats / Dead Pedal cover (to match other pedals) / ARH Catless 1-7/8" headers + ARH X-pipe + AWE Touring Axle-Back / Diode Dynamic smoked side markers / American Authority tow hook

04-18-2020, 06:02 PM	#10
SJFGTO Oh Oh it's Friday Night! Drives: 2018 ZL1 1LE Nightfall Gray Join Date: Jan 2018 Location: Walton Woods Posts: 1,061	Interesting. I have 2 inch ARH headers which were installed by Vengeance Racing. Not an issue at all on my ZLE. I agree with the above post that the install can head off this potential issue in advance. __________________ 2018 Camaro ZL1 1LE NFG; ARH 2” headers, catless mids, ARH full exhaust, Lingenfelter 18% lower pulley, ATI Harmonic Balancer, Roto-fab CAI, EE-catch can, TM ported TB, NX Lid, BMR strut tower brace. Aeroforce dual pod interceptor gauges. Tuned by Vengeance Racing!!! 644 HP @ 6250 rpm / 689 trq @ 3660 rpm Four that wanna own me Two that wanna stone me One says she's a friend of mine...

04-18-2020, 11:27 PM	#11
XXX ZL1 Drives: 2023 ZL1 M6 Join Date: Sep 2018 Location: Pace FL Posts: 417	I wrapped mine in heat tap and zip ties with the push pins on the end to secure the harness to the frame rail. Tons of room now. __________________ 2024 Riverside Blue ZL1 M6 Magnuson 2650R, NW 103, Roto Fab Big Gulp, Jet Hot Coated ARH 2 inch LT's, Stainless Works NPP, Too High PSI Billet Valve Covers, Mighty Mouse Wild CC Signature Forged 20x10.5/20x11.5, 295/30-315/30, BMR springs, BMR Cradle lockout, AAD Billet Control/Trailing arms 2023 Vivid Orange ZL1 M6 - sold 2019 Riverside Blue ZL1 A10 - sold

04-19-2020, 03:55 PM	#12
waterman Drives: Grandad's C2 L89 Join Date: May 2017 Location: 2051.50N 15629.60W Posts: 1,711	__________________ 2018 ZL1 1LE sw/PDR

02-11-2019, 04:02 PM	#2
Can'tHave2MuchHP Drives: Fast Join Date: Mar 2015 Location: Michigan Posts: 3,696	Good post. Though I feel like the installer should thoroughly check for good clearance at all points so this probably "shouldn't" have happened...But sounds like this was a car-to-car issue that was a GM assembly error.

02-11-2019, 04:05 PM	#3
Jason18ZL1LE Drives: 2018 ZL1 1LE Join Date: Apr 2018 Location: SoCal Posts: 134	You are correct, this could have been spotted however the installer hadn't been doing too many ARH systems due to the cost but I was insistent that we use ARH. Fortunately due to this he was able to go back to the ARH systems hes installed lately and revise them. He did say there is some variance in the slack on the harness. What actually happened is there is too much slack which caused it to bow out towards the header. Consider this a learned experience.

02-11-2019, 05:49 PM	#4
2018ZL1 Drives: 2018 ZL1 A10 NFG Join Date: Feb 2018 Location: Woodbine Md Posts: 655 View My Garage	I just installed the 2 inch ones on mine! I am gonna have to take a close look at this. I had mine ceramic coated so I wonder if that would make a difference???

02-11-2019, 06:17 PM	#7
Jason18ZL1LE Drives: 2018 ZL1 1LE Join Date: Apr 2018 Location: SoCal Posts: 134	Also to be clear this harness is running from firewall to the front of the fuse box, not along the firewall. This is the factory location for the harness

User Name		Remember Me?
Password