351w, maverick header help

With a 351W in my 66 Muskrat I have 2.5" from the header mounting surface to the stock shock towers. That is about the same as a Maverick with a 302 in it. Headers for a Maverick might fit into a Mustang but no header made for a Mustang is going to fit in a Maverick.

 

Hey man, I have a 351w in a Maverick myself. I'm gonna shoot it to you straight.There are other Ford cars out there that look very similar under the hood in the engine bay. For instance, the 65-66 Mustang, at it's closest point on the shock towers, is about 1 1/2 inches further apart than the Maverick. To spite the Mustang being older and using the 260ci. and the 289ci. engines, you would think that the headers that are made for the 65-66 Mustang with a 351w would be a sure bet. Wrong. There are no headers made for a 351w in a maverick. I recall seeing an ad in a Summit catalog, where a Maverick with a 351w, was a vehicle on the list for a particular set of headers to fit. Wrong. My Maverick has a Hooker on the driver side, and a Headman on the passenger side. That is because that is the closest I could find to fit it. On top of that, BOTH headers have been cut and welded with angles changed/altered for them to fit my Maverick.Especially the rear tube on the driver side that had to be modified for the steering box. To get headers to fit a 351w in a Maverick,takes trial and error. I had my engine in and out a dozen times, marking tubes, cutting tubes, welding tubes, until I got it right. When all was said and done, I had three tubes modified on the driver side, and two tubes on the passenger side. I too, didn't know what I was getting into with the 351w swap. Both header sets I bought were for a 351w in a 65-66 Mustang, and I have both my shock towers cut as far in and as far down as they could be without interfering with the shock absorber and a-frames, and then welded back in with 3/16 inch steel plate. I truly don't believe that there is a miracle fix for your problem. Mustangll front suspension or Kooks headers would offer an effective, but costly alternative,with a set of Kooks headers costing around $800.oo-$1000.oo. For guys like us it's trial and error, do it yourself, or else. If you are using the 351w just because you want to, or that is the engine that you happen to have at the given time,you are better off with the 302, for ease of installation and routine maintenance, as the 351w makes even that a chore.

 

I am in the middle of a 351 swap right now. I have put the stock maverick manifolds on and they fit, all but one of the ribs touches the steering box on the drivers side, but that piece would be easy to grind off. I am going with headers though, I was just curious.

 

Shortening the tubes at the flange is the best idea I have ever read. Gotta be careful due to flow concerns maybe. A dyno could prove and maybe. Thanks

 

The 1996-2001 mountaineer 302 manifolds work;Its a little tight but, I have full clearance on both sides still have to grind off some of the end touching the steering box. I'll post some pics once i get back to my garage.

 

Shortening the tubes at the flange has pitfalls .... the first and third tube on the driver side exit at such a steep angle that you have to insert the bolts shrouded by the tubes first and pull the header to the head with them. This is using small head bolts and turning them with an ignition wrench.

The header tube size on mine are small, too.

I did the 351W swap in the mid-1990s. That was the way to get cubic inches back then. Now, stroker kits abound. If doing it now, (and I will if this motor gets tired), a 331 would be my goal. Good heads are easily available now, too. Then it would be easy to get headers for a 302-based motor with decent tube sizes that actually fit the car. .... win, win, win!

Also, you will have a hard time packaging the 351W under the hood if using an intake manifold with any additional height to it.

All that being said, trim the shock towers back, even with a 302-based motor .... much easier to wrench on.

 

"Shortening the tubes at the flange has pitfalls .... the first and third tube on the driver side exit at such a steep angle that you have to insert the bolts shrouded by the tubes first and pull the header to the head with them. This is using small head bolts and turning them with an ignition wrench."


I agree with CaptainComet. I also made my 351W swap in the mid ninety's. I had to use multiple length header bolts plus multiple head size bolts on the headers, tightening them with as-you-say with ignition wrenches. I had to keep an eye on the bolts as they would work loose. In addition I had to use heat sleeves to protect two of the plug wires.

As for hood clearance, I ran an Air Gap manifold 1" spacer, 14" drop top air cleaner. My Comet's hood is functional so the air cleaner would stick up through the opening into the scoop.

I still have the custom made headers by JBA in case I ever want to revert back to 351W power. Not!!!!!!