USA Made Quality Control:

Inspector #20

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So, recently, i began to get fault codes for catalytic converter efficiency, which at 224,000 miles, wasn't surprising.

I'm actually fond of the clean exhaust smell of a catalytic converter equipped vehicle, so i sought a 'direct fit,' California Compliant replacement from Magnaflow, made and shipped from Oceanside, California.

I needed to pass smog recently, so i wrote a custom tune that leaned fuel mixture and spark timing, which allowed the catalyst monitors to set and the car passed smog with no issues.

Yesterday, i took some time off to install the new cats on my friend's hoist.

The monolith in the old cats looked remarkable for 224,000 miles:

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But, the chemical compunds break down and they gradually become inefficient.

So, i move on to installing the Magnaflow catalysts.

The flares at the flanged sections didn't look right, but i installed them anyways. Overall, the install was very slow because the pipes had odd bend angles and the fit just wasn't good like the factory catysts.

I then discovered that i could not tighten down the flanges because of the mis-shapen flared sections, which resulted in a huge exhaust leak from the left bank on startup.

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Magnaflow was contacted and advised to just "run the bolts up with an impact and it will seal." They even confirmed the replacements they would potentially send me looked just like the one i now have.

I was floored...break an ear off a manifold or strip/break a stud??? No way...

So, i spent about 3 hours yesterday afternoon for nothing.

Grrrrrr....!!!!!
 
That stinks. Guess I was lucky on my Civic. Flange on the original muffler rusted off at somewhere around 150k. Went to my local Napa and purchased a new muffler. Everything fit perfect. Went back together and no leaks.

My biggest issue was I broke one stud trying to take it apart. Did a little trick I learned from a service manager I worked with nearly 40 years ago. All I had was a propane torch so I hoped it would put out enough heat. Was actually able to get the metal around the broken stud cherry red. Then poured water on the area. Using vice grips on the exposed threads I was then able to screw the broken stud out. Before the heat/water thing, vice grips just spun on the threads.
 
I gotta head back this afternoon and swap in the old catalysts, box up the Magnaflows and get the return started.
Robert, this is extremely common with aftermarket performance automotive parts. Generally very small companies with minimal quality control. I used to run into this all the time.

Agreed, I have seen a lot of issues in my past work as a fabricator, but I wasn't expecting it from Magnaflow with a Direct-Fit, Made In USA catalyst...
 
That stinks. Guess I was lucky on my Civic. Flange on the original muffler rusted off at somewhere around 150k. Went to my local Napa and purchased a new muffler. Everything fit perfect. Went back together and no leaks.

My biggest issue was I broke one stud trying to take it apart. Did a little trick I learned from a service manager I worked with nearly 40 years ago. All I had was a propane torch so I hoped it would put out enough heat. Was actually able to get the metal around the broken stud cherry red. Then poured water on the area. Using vice grips on the exposed threads I was then able to screw the broken stud out. Before the heat/water thing, vice grips just spun on the threads.

Heat the broken.stripped stud and melt a birthday candle on the threads. You won't believe it until you try it...
 
Ok,

So, as i contemplate this matter more and more, it's clear that the factory Ford replacement H-pipe would be the best option in terms of fit. However, the sheer principle of this has been so upsetting that I am resolved now to just set the original catted h-pipe aside for future smogging and construct something to correct this issue once and for all. I like having a clean exhaust system and being in compliance with all applicable states and regulations, but this has really twisted my thought process.....
 
Ok,

So on a Ford of this vintage. the rear oxygen sensors serve only one purpose - to tell the PCM that the catalysts are operating within an specified efficiency parameter. They are part of the catalyst monitor circuit. Knowing the Ford PCM sends an approximate 5VDC reference signal to the oxygen sensor, its signal voltage jumps up to 0.8 to 0.9VDC when the air/fuel mixture is rich, and drops to around 0.3 volts or less when the air/fuel mixture is lean.

By incorporating a 1 MegΩ resistor and a 1.0uF capacitor, I can send a constant 0.5 to 0.6VDC signal to the PCM. which would staisfy the catalyst monitors and prevent a CEL even if the car had no catalysts at all.... :)
 
Heat the broken.stripped stud and melt a birthday candle on the threads. You won't believe it until you try it...
I can see how that could work too. The trick I learned was just a metallurgy thing. Heat it with the torch. Cool it rapidly with the water. Expand/contract. Breaks the rust bond. And yes. With it cool, it also got a good dose of PB Blaster.
 
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Ok,

So, as i contemplate this matter more and more, it's clear that the factory Ford replacement H-pipe would be the best option in terms of fit. However, the sheer principle of this has been so upsetting that I am resolved now to just set the original catted h-pipe aside for future smogging and construct something to correct this issue once and for all. I like having a clean exhaust system and being in compliance with all applicable states and regulations, but this has really twisted my thought process.....
You sound a bit like me. Clean installation. I once spent half a day fabbing a brass connector for a vacuum line. Swapped the OEM carb and manifold on my 350 for an Edelbrock and Holley. Hole on manifold was too small for OEM line..... so I built an adapter from a brass nipple and coupler. Bit of drilling. Some JB Weld. Chucked the finished assembly into a drill to polish it up. You can’t tell it was fabbed and not a purchased adapter.

Edit: Yes.... I did try a little bit to find an already available adapter. I’ve done this for a living since about 1980. Parts department. Tractors/combines now boats. I’ve never seen an adapter that went from the size NPT nipple to the bigger size female fitting for the vacuum line.
 
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Robert, I am sure if the Magnaflow was mated up to brand new flange it would seal up fine. Put up some pics of the 2 Cats pipe ends side by side for us to look at? Also, I know you don't feel as if you should need to do extra work with NEW parts, but you are dealing with mating NEW to OLD and we are talking exhaust now aren't we? Exhausts are thin metal, bent to various shapes and bolted together to carry gases. Whenever I work on exhausts nowadays, I am always prepared to use a torch, welder, sawzall, lift and lotsa cussing. Heck, it looks like you are close enough fit there. What about some sort of lapping type treatment on the 2 parts to make them mate up?
 
Dremel and abrasive wheel. Shape the Magnaflow to match the Ford H pipe? I could do all manner of things, but I am sure you will come up with a solution, Robert.

For me, most of my life the hardest obstacle was not having good access to the underbelly of a car, ( no lifts working in apartment complex parking lots.) Getting access to a lift should make your solution to this problem a piece or cake. Robert.
 
Dremel and abrasive wheel. Shape the Magnaflow to match the Ford H pipe? I could do all manner of things, but I am sure you will come up with a solution, Robert.

For me, most of my life the hardest obstacle was not having good access to the underbelly of a car, ( no lifts working in apartment complex parking lots.) Getting access to a lift should make your solution to this problem a piece or cake. Robert.
That’s a big 10-4. Been turning my 1977 Vette from single into dual exhaust to true dual exhaust. I have jack stands as high as they go and laying on my back on a creeper. It sucks. On a lift, the job would have been completed a long time ago. I’m too stinkin’ old and my body no longer allows me to play that game.
 
Robert, I am sure if the Magnaflow was mated up to brand new flange it would seal up fine. Put up some pics of the 2 Cats pipe ends side by side for us to look at? Also, I know you don't feel as if you should need to do extra work with NEW parts, but you are dealing with mating NEW to OLD and we are talking exhaust now aren't we? Exhausts are thin metal, bent to various shapes and bolted together to carry gases. Whenever I work on exhausts nowadays, I am always prepared to use a torch, welder, sawzall, lift and lotsa cussing. Heck, it looks like you are close enough fit there. What about some sort of lapping type treatment on the 2 parts to make them mate up?

The radii of the 'cup' (flare) on the Magnaflow pipe is wrong. That manifold is cast iron. It cannot be deformed and there is no corrosion or pitting on the 'cone' section. It's just plain made to the wrong specs....
 
I've done a little fabricating, but honestly, I try my best to avoid it on my daily driver....

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Know what I mean????
 
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