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With the misalignment shown in my pictures, this is with the slip fit connection completely bottomed out on the header. So zero "gap" and 100% overlap.
It's like the bend is in the middle of the extension having equal leg lengths. But for me the bend needs to be closer to the header and the 2-bolt flange leg be extended longer to fit to the midpipe. If this pans out how I'm thinking, all I need to do is to splice in a ~1" piece of 3" tubing to each extension.
I could MAYBE slide my midpipe forward, but with the stock manifolds, the midpipe was slide ALL the way onto the axle back pipes (reaward). I think there is enough hanger length on the midpipe to slide it forward and I believe enough slip fit overlap in the midpipe to axleback pipes to do this.
I should have marked the location of the stock downpipe outlet with a marker on the tunnel to see how the headers/extensions compare location wise. Would have been a useful aid in making these tweaks. Right now I'm using the location of my tips in the rear facia as a starting point since I know how those looked before I started.
This all seems lengthy and troublesome, but if anyone has basic fab skills this is easy work.
Another 3hours put in tonight. One header wrapped.
.041” stainless safety wire, wire cutters, pliars to twist and needle nose to bend each end around in a loop. Hopefully the carpal tunnel doesn’t set in tomorrow 😆
They say NOT to fully cover the pipes so the inside is allowed to breathe a little.
Last edited by smitty2919; Mar 4, 2026 at 09:32 PM.
Headers have been on for a week. No leaks and no issues. I was actually able to finagle the midpipe and extensions to a point where no modification was needed to the extensions. Being ****, I WOULD still modify them but they are on and leak free. The angle at which the extensions meet the midpipe aren't "inline" and are lightly crooked. But the ball/socket style flange allowed for some misalignment.
I will advise you to check all the o2 connectors and double triple check that they are up tied off out of the way!! thought I had mine secured and now I have a mess to fix just days before a big road trip
and I love the thermal wrap you did that looks awesome
Headers have been on for a week. No leaks and no issues. I was actually able to finagle the midpipe and extensions to a point where no modification was needed to the extensions. Being ****, I WOULD still modify them but they are on and leak free. The angle at which the extensions meet the midpipe aren't "inline" and are lightly crooked. But the ball/socket style flange allowed for some misalignment.
Are you able to install the tunnel plate back underneath the midpipe?
14k mi
M7 manual
1 7/8” EOS headers
stock catted x pipe
stock C7 NPP mufflers
headers gained 19/34 over stock
headers and 55% E85 gained 37/58 over stock.
The LT1 direct injection likes E.
just to clarify and so everyone can know what the setup is the eos headers are actually 1.875 " not 1.78 slightly bigger than most 1.75" and just smaller than the standard 2.00"
just to clarify and so everyone can know what the setup is the eos headers are actually 1.875 " not 1.78 slightly bigger than most 1.75" and just smaller than the standard 2.00"
Thank you, no problem you're welcome. With how these fit, I would never justify a set of SW/ARH/Kooks set for $2000+ AND having to get a matching midpipe.
Props goes to @9sec for his thread that I saw first and convinced me to get a set. At $600 I was willing to cut/modify to make them work. Luckily, no modifications needed.
I agree. Tremendous work gentlemen. I’m in a conundrum, I would rather buy these but shop that I want to do my heads/cam will only work with ARH and Kooks so I might be forced to pay up.
I agree. Tremendous work gentlemen. I’m in a conundrum, I would rather buy these but shop that I want to do my heads/cam will only work with ARH and Kooks so I might be forced to pay up.
Do you have a garage spot to do these at home with tall enough jackstands?
I understand as a friend of mine owns a speed shop and will usually charge customers MORE if they bring their own parts LOL. Rightfully so as I have witnessed some really poor fitting stuff when I would go down and hang out. I do my homework though.
I did the same when I bought a set of TPS RPM Headers for couple hundred dollars a couple yeard back from TPS Motorsports for my C5Z. Those were also 1 7/8" and fit AMAZING. I avoid anything Texas Speed and anything off Amazon/Ebay.
I have not asked that specifically but based on our conversations they likely would refuse and make me purchase ARH anyway to reinstall. This is the most famous shop in Delaware. They know what works and stick to it I guess.
