351 header clearance issue after dropping in a new engine

[carpesdiem]

Hi All,

FF5 MKII had a 302 in it. Upgrading to a 351 windsor 216695216696216695216696stroked to a 408. Bought the 351 headers from FF5 recently and when i now try to bolt them tight they end up hitting the body where they come out for the side pipes. Does anyone have any other ideas besides cutting the body since it was just repainted? Please and thank u

[Jeff Kleiner]

You can add 1/4" flat shim which will move the entire pipe outward increasing body clearance at the pipe's inside radius.

https://breezeautomotive.com/shop/1-4-sidepipe-flange-spacer/

Are the pipes parallel with the body? If the rear of the pipes are closer to the body than the front a tapered wedge to kick the tip outward will also help the inside radius to body clearance. This is the 1" wedge but others are available.

https://breezeautomotive.com/shop/side-pipe-1-adjustment-wedge/

In the end it may take a combination of both.

Jeff

[JMD]

How far away is the tip from the body? If you bring the tip out does it give more clearance? It may need to either put a spacer in where the sidepipes meet the header to push them further out or clearance the opening.

Also check to see if the engine is level (compare oil pan to frame rails). Mine was at a bit of an angle when I first installed it and dropping one side down to level it helped orient the sidepipes into a better position. I still had to cut a good bit out from the rear of the passenger side opening to make enough space for it. Cutting isn't ideal, but if you're careful and mask with tape and touch it up you'll probably never notice unless you looked for it. (Which you would, but most anyone else wouldn't.)

Ah, you got a response from Sir Jeff while I was typing. Just listen to him. ;)

[CraigS]

If you do end up needing to cut, don't cut. Use a 2" drum sander on a drill instead. Don't go too hard or too long so you don't heat up the f-glass/paint. Be real careful so the drum doesn't jump out of the opening and run across the paint. Double layers of masking tape for 6" all around the opening is a good idea. Using the drum, all you end up w/ is the edge of the f-glass needing touchup. You can do that easily w/ a standard touch up paint stick and no one will see it due to it's location.

[Rebostar]

If you swapped out 302 with a 351 the deck height would be about 3/4 higher which will raise the headers about the same amount. As mentioned above use a fine drum sander, put high quaity painters tape where you want to trim. Go slowly and move around, you dont want the paint to heat up.
Best of luck

[Ford & Jeep Fan]

If you swapped out 302 with a 351 the deck height would be about 3/4 higher which will raise the headers about the same amount. As mentioned above use a fine drum sander, put high quaity painters tape where you want to trim. Go slowly and move around, you dont want the paint to heat up.
Best of luck

Correct increased deck height also means farther out to the side as well.

[carpesdiem]

Thank you all for the great suggestions. I believe Jeff Klieners response will work perfectly. You guys are great

[Jeff Kleiner]

If you swapped out 302 with a 351 the deck height would be about 3/4 higher which will raise the headers about the same amount...




Correct increased deck height also means farther out to the side as well.

He already told us that he has the FFR 351 headers which bring the collector out to the original cutout location.

Jeff

[bobl]

Looks like the headers are exiting too far rearward. I've run into that problem a couple of times when changing to the ball end headers. Had to cut and put an offset into the side pipe adapter. If they are the the older style you may be able to use a combination of wedges to get clearance. It appears you have plenty of clearance on the front side, so I would be hesitant to trim the back side for fear of the opening being too large.

Bob

[JRL16]

Another option would be to use the drum sander and then DAX cobra in Europe has a chrome trim piece that goes around the side pipe opening. A little difficult to fit as their bodies are flat in front of the sidepipe hole and FFR is not. Have to hone your finished metal bending skills but it can be done.