[RACER X #99]

I have had the same engine as you have and unless you are looking for some track HP save your money and keep the 351. I think the GT40 heads are too small for a 408.

I had the gt 40 heads ported by a pro and they were marginally better on the 351 but not noticable enough to warrent the expense. You can buy a set of Victor Jr's for a little more than a good port job on the Ford heads and they work a lot better.


If you want more power sell the 351 and buy a World products or Dart block and have your engine builder put something together for you with some better breathing aftermarket heads. Jr's AFR.

Putting a lot of money into a stock 351 block just does not make sense to me. The block is weak and you will have to bore .030 over to get to 408 with your 4"stroker and you are really putting a lot of strain on a weak block.

Some will disagree but I have done both and I would not build another stock block 351.