PROS and CONS of a high compression head

[freak]

That said, I have one and it's been running fine for 10's of years.

[TerryH]

Most high compression heads do not add 20 hp; using Snyders 5.5 or 6.0 will probably net you around 10 more hp. As for extra wear and tear on the engine, yes if you drive hard and push it all the time, and aren't careful with timing and spark advance, you can do some damage. Many, many of our local club members have them, and they are probably the single most effective way to give your A a significant power boost without compromising the car. I have a Town Sedan, which is one of the heavier Model A's, and it certainly helped.
Terry

[Marco Tahtaras]

They are a great addition. They don't do a good engine any harm. However owners ARE more likely to cause harm primarily due to improper use of timing advance. The low compression on the stock engine is very forgiving of misuse. The higher the compression, the more critical the proper use of timing becomes.