I'm new to this site and I've been seeing some stuff I have no clue about. Like these compression numbers (9:7:1 or 11.7:1) sometimes theres 2 numbers somethimes there's 3. what do they mean. There should be a 'Basics' section of this forum where all the educated people post what they know about a topic but no newbs can post. If there is a section like this will someone direct me to it. Theres a lot of other things I have no clue about, like the interchangable enigine components, but I'll save that for another day. Thanks.

 

There is a nifty feature called "Search" on this site. Granted, it is pretty garbaged up, but if you have the time and patience to weed through it, you can learn a few things.

When you refer to 2 or 3 numbers, do you mean 9.7 vs. 11.7? It's a ratio. If the ratio is high enough, additional digits are required to state that. Sort of like $9.95 vs. $11.75.