Our 1917 runabout has served us well on several tours in the past few years. It is smooth and reliable. Still, we wished that it had a bit more power on some of the steeper hills. This edition we find out the easiest way to get more horsepower and torque from any Model T Ford. We install an aluminum high compression cylinder head.
The instructions and photos here can also be used to guide the replacement of the head gasket for any Model T with any sort of cylinder head. If you have a cast iron head then any of the available head gaskets will work fine. My preference would be for the one that is cheapest.
When installing an aluminum cylinder head there are some general rules that need to be followed if you are going to be successful. First of all, there needs to be a washer under every head bolt to keep the head from being damaged every time the bolt is rotated. Second, the length of the bolts is invariably shorter than it was before, so you need to make sure the bolts that you install are the proper length. Third, aluminum rots away quickly in the presence of pure water. Make sure that you have an appropriate mix of ethylene glycol and water. Fourth, aluminum and copper head gaskets are not compatible, nor are aluminum and graphite head gaskets. It is always best to use a steel or composition head gasket with an aluminum cylinder head.
Here’s a link to the Langs head gasket that we used: https://www.modeltford.com/item/3002A.aspx
Today we started by re – torqueing all the head bolts. It was shocking how loose some of them were now that the engine had cooled. A compression test revealed the new cold cranking pressure was 60 PSI in all four cylinders, markedly up from the 45 PSI readings taken before the high compression head had been installed.
After that, we reinstalled the dash shield, plugs, and floor boards for a quick drive around the neighborhood. Power was much improved. The car is easier to drive than before, first gear does not need to be “wound out” as high as before. While it is probably capable of a higher top speed, we won’t be driving it any faster because, after all, it’s still a Model T. The steering and brakes are not adequate above typical Model T speeds. We expect this extra power will be very handy when climbing hills on the next tour.