Several factors together make more horsepower than what your motor has now. They are:

1. Change-out the cam and valves. Your part store, or news stand has a book on the possibilities. Racing cams come in several possibilities. The more the cam lobe holds the valves open, the more fuel that can be sucked into the cylinder – and more fuel crammed in the cylinder, results in more horsepower development. Sometimes, this calls for machining of the engine head. One type machining shaves-off metal to help raise the compression – a power-increasing factor, all by itself. The other machining makes room for new valves, with bigger heads, which also allow more fuel into the cylinder. About the cam. The more radical the cam lobe duration and degree, the longer the valves stays open to let fuel in, and the higher the power output. But, the rougher the low speed idling will become – You may have heard the souped-up car next to you at a red light rumble, and noticed the idle speed was much higher as it idled. Who cares, if your serious abut hot-rodding. A thought. New souped-up engine heads is often a good choice here – along with a midrange racing cam.
2. The Chip. My son Nic had to have a newer Ford Excursion turbo-charged diesel. It average over 21 mpg. Of the experiments he did to “soup it up a little,” was to upgrade the motors “computer chip.” It came from some mail-in place – where the ad glowing talked about, what their chip modifications will do -blab, blab, blab. It now delivers 18 mpg – and to do so, he has to drive ten miles an hour slower – to get that good a mileage. In my opinion, if he was pulling a boxcar full of cement up a long grade – maybe the chip might work. I think the jury is still out on chips, though. Nic is out about $100 or so, and never brings it up any more. Engine timing must be adjusted when improvement of some sort is made. I don’t know if he got the right chip to do that – Also, the injector spray duration needs to be altered – Don’t know if the chip did that, or not. All are factors for more power output. Dyno testing works this out. Read the rest of this entry »