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CFranks
06-08-2019, 03:43 PM
Hello all,

I’m tweaking my exhaust cutouts and having a little trouble with the driver side. The header flange is really close to the body, as you can see the top of the exhaust flange when installed is about 1/4”inch from the body. This means the nut will rest on the body when installed, and will obviously melt it. Elephant ears are NOT on yet. I’ve trimmed the opening upward about 1/2” but reluctant to do anymore unless consensus says I’m supposed to. Is this normal and should I open it up another 1/2-3/4” upward? The edge of the top nut will be flush or just be peaking out past the body cutout.

I have zero interest in playing around with the engine location on the mounts so hopefully this is normal.

Passenger side is perfect.

Thanks,
Craig 108512108513

Railroad
06-08-2019, 03:49 PM
I would look into heli coiling the header. You may have to use a larger bolt, but the bolt will not protrude through the header flange. I would also grind the edge of the flange to clear the body. It looks to be stainless, so no issues with plating or coating.

michael everson
06-08-2019, 04:54 PM
Is this a 351 based engine? I have run into the same problem twice now. Not 351 based engines. A Heli-coil is probably the best solution.
Mike

CFranks
06-08-2019, 04:59 PM
Is this a 351 based engine? I have run into the same problem twice now. Not 351 based engines. A Heli-coil is probably the best solution.
Mike

Thanks. Yeah, it’s a ford racing 427x with a 351 boss block.

Murd
06-08-2019, 05:09 PM
I had a similar issue with a 302 setup. Two things, I put the nuts to the inside and once I put the elephant ears on it pushed the body out quite a bit. I’d do that before you do anything else permanent.

frankeeski
06-08-2019, 07:09 PM
Hello all,

Elephant ears are NOT on yet.

Thanks,
Craig 108512108513

I think you answered you're own question. Install the front wheel well rear pieces (elephant ears). Until then, you're just wasting your time.

CFranks
06-08-2019, 08:00 PM
I think you answered you're own question. Install the front wheel well rear pieces (elephant ears). Until then, you're just wasting your time.

Thanks. I mentioned the elephant ears because I wasn’t sure if we were supposed to use them to push out the body or trim them to keep the body as currently shaped. I’ll trial install them and go from there, I don’t believe I’ll need to cut anymore.

Jeff Kleiner
06-09-2019, 05:43 AM
It's actually fairly common with the 351 headers. I use button head bolts installed with the head to the outside to gain some additional clearance between the bolt head and body. As Frank mentioned the elephant ears can push the lower edge of the body out a bit. If you're going to thread anything it would need to be the pipe flange, not the header because threads in the header would still leave the bolt head in the same relationship with the body.

Jeff

CraigS
06-09-2019, 06:47 AM
Not sure why you have 'zero interest' in messing w/ the mounts as they can be a huge influence on header location. Put a piece of plywood on your floor jack and place it so it will lift the passenger side pipe. Loosen the bolts that attach the mount to the engine block. Remove one at a time and put a washer between mount and block, reinstall the bolt. Drop the floor jack and see how your headers look now. Also, the elephant ears can push the body out. But looking down from the top, the way the body is rolled under the rocker panel area, makes it very stiff from header cutout to rear wheel well. So, if you push it out at the header, it will also be pushed out at the door opening. keep this in mind.

CFranks
06-10-2019, 07:51 AM
Thanks all for the responses. I tightened everything up and used a button head bolt in reverse as per the recommendations here, seems to be heading in the right direction. I have about a 1/2” clearance between the bolt head and the body, which hopefully I should be able to nudge out a bit more with the elephant ears. If not I’ll move the engine on the mounts as per CraigS’s recommendation, I was just trying to avoid that since I had the PS side dialed in perfectly.