[Walt Fricke]

Bruce Anderson has some useful discussion about the 2.8 race motor, and the effects of using 92mm ps and cs with stock 2.7 heads.

The real 2.8s produced 308 or so DIN hp at 8,000 rpm advertised. They used titanium rods. They have really big ports. Most importantly, I think, was the fact that they used 49mm intake valves. To get these into a 92 [edited]mm bore, they changed the valve angle. You can take any of the 2.2-2.7 heads and open up the ports, but changing the valve guide angles and relocating larger valve seats might cost as much as a set of custom aftermarket heads?

I don't know if using 3.0/3.2 heads would cause valve to cylinder interference with a 92mm bore. I do know that it is difficult and expensive to move the head stud holes in these heads in to the spacing used on the 2.7s and earlier. Peter Dawe did this on one of his race motors, I think. Called for cutting and welding here and there to make sure you didn't get some walls too thin.

Using stock valved heads on a 2.8 replica with a variety of cams, you can for sure get 250 rear wheel HP. These are, of course, race motors. Don't know just how well they would drive on the street. Mine doesn't idle through the paddock all that well going over to the grid.

You can have your aftermarket pistons cut and pocketed to avoid too much compression, so that's not a tricky bit.