Reply to "351c EFI intake manifold"

Doug,

Raised port heads? Has somebody other than Thomas Tornblom done the conversion? I am aware of only two conversions, Thomas' and an american's, a gentleman named Jim Murch.

the basis for the conversion is the Trick Flow 351W FI manifold base. The runners of the manifold are pretty much in the same location as the 351C 2V, they are a tad smaller and more rectangular, whereas the 351c 2V runners are a bit more oval (corners more rounded). There is plenty of meat in the Trick Flow intake casting to grind them to the same size as the 351C 2V. Thomas Tornblom mated his manifold to a Aussie 351C motor, with small port 2V heads. Jim Murch, has done the same conversion mating his manifold to the 4V heads. He found plenty of meat around the runners to grind them open to "almost" the same opening as the 4V head ports. (see pic below). A 2V port lines up in the lower right hand corner of the 4V port. The Windsor/2V runners also line up with the ports in the Ford/SVO heads, only needing a height adjustment. For instance, David Berman's engine builder modified an Edelbrock Performer 2V manifold to mate up with the high port Yates heads on David's motor. Since the Windsor block is taller, making the "vee" wider, the wider Windsor manifold sits higher in the "vee" when it is installed on the 351C block, since the Cleveland "vee" is narrower. I can't say if it aligns properly with the ports in the Ford/SVO heads (A3, B351, C302), but it can be adjusted one way or the other.

Ignoring the un-needed water neck in the front of the manifold, there are 3 operations that must be performed to the Windsor manifold base to mate it with the Cleveland heads & block.

(1) The rear "valley rail" of the Windsor block curves outward, the rear valley rail of the Cleveland block curves inward, so the manifold's rear valley rail mating surface must be welded up to create a new inward curving mating surface, machined flat and then cut to the Cleveland shape. You can see the outcome of this operation in the picture below, looks like it was cast that way from the factory.

(2) The Windsor manifold bolts are all oriented vertically, whereas the Clevelands manifold bolts are a mixture, the two in the middle on each side are vertical, but the outer bolts are perpendicular to the head. The manifold base must be redrilled for the perpendicular orientation of the outer bolts.

(3) The Windsor block has a 9.5" deck height, the Cleveland deck height is 9.2", so some material must be machined from the manifold base to allow it to sit at the proper height in the narrower "vee", unless of course the intake is being mated with a high port SVO head.

So Doug, are you ready to put the A3 heads & Webers on the shelf and bolt on a set of C302s and an FI intake?

cowboy from hell