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Old 07-30-2013, 11:14 PM   #1
Steve Cole
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Please read.. Is This normal

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Old 07-30-2013, 11:52 PM   #2
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Re: Please read.. Is This normal

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I have aftermarket headers on my truck, (Hedman) the drivers side hangs down 3/4" lower than the passenger side. Actually the drivers side looks right, the passenger side looks too high. I discovered this when I went to install my new Magnaflow exhaust system, ( p/n 16643). The driver side went on no problem but the pass. side wouldn't clear the transmission crossmember. I inspected both headers and neither side looks tweaked or bent. The two pipes that connect to the collectors go into an "X" pipe then continue on to the back. Because the one side doesn't fit, neither side will work because they are connected together by the "X" pipe. Also, my headers are 1" wider than the two pipes that connect to them. So for this to work, my right header needs to be 3/4" lower and the two header pipes need to be 1" closer together or this mandrel bent exhaust needs to be reworked. I'm at a loss as what to next. Is this common for one header to be higher or lower than the other by this much?

Any advise appreciated. Thanks
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Old 07-31-2013, 12:05 AM   #3
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Re: Please read.. Is This normal

The magna flow system is a cat back system. It does not take into account what manifold or header you using. You will have to modify to meet your needs. It's not uncommon for one header to be slanted different than the other.
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Old 07-31-2013, 12:37 AM   #4
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Re: Please read.. Is This normal

The SBC cylinder heads are offset... so the drivers side header will be a little more forward than the passenger side header by about an inch.

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Old 07-31-2013, 07:59 AM   #5
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Re: Please read.. Is This normal

IIRC when I had headers on mine, both sides ended up at the same level and it seems like one collector was a bit longer than the other to compensate for the one head being slightly (one lifter width) forward of the other.

But I remember them being uniform.

Those are my only header experience and it was 30 years ago.
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Old 07-31-2013, 08:11 AM   #6
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Re: Please read.. Is This normal

take some measurements to verify your engine's sitting level and try another brand of headers...contact magnaflow and see whose they might recomend
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Old 07-31-2013, 09:12 AM   #7
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Re: Please read.. Is This normal

i would check my motor mounts to see if they are causeing the engine to not sit right
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Old 07-31-2013, 09:24 AM   #8
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Re: Please read.. Is This normal

Motor mounts are the first thing that comes to mind. Header manufacturers know that the cylinder heads are offset and make the headers to end evenly. I buy the brand and model I want and wouldn't want Magnaflow telling me what headers to use. I always wondered how anyone could make a bolt-on exhaust system to fit any manifold/header. That's why I still have custom exhaust made. I think the benefits of mandrel bent are never realized in most applications,but if I had to have that I'd pay more and have a custom mandrel bent system done. If you come up with no other solution,you could always have an x-pipe made to work or modify the out of box one.
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Old 07-31-2013, 09:53 AM   #9
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Re: Please read.. Is This normal

I can tell you on a BBC, the headers NEVER come out sitting the same. Driver's side is always longer and the angles will be different. I just installed temp mufflers on my ride and it's pretty funny to get under there and see how different they hang. It was the exact same way on my Camaro.
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Old 07-31-2013, 11:47 AM   #10
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Re: Please read.. Is This normal

Depending on the model of Heddman headers. The high end ones migh be a better fit. But if you bought the cheapies... Then I would be supprised if they lined up well.
Also, the made to fit exhaust system you have is most likey designed to fit their brand of headers and asume that other manufacturers are close enough.

A little tweaking is in order for you.

I would check the motor mounts just to make sure the motor is not leaning
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Old 07-31-2013, 12:16 PM   #11
Steve Cole
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Re: Please read.. Is This normal

I called Hedman and Magnaflow. No luck with either one. Magnaflow said their system may require some cutting,tweaking or welding to work with different headers and that the system was designed to fit the truck not a particular header/manifold setup.

BTW... These headers are not "cheapies" they are the "elite" series, ceramic coated long tube headers. Cost about $600. I Will make this work, just going to be a PITA!
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