08-25-2019, 04:21 PM
|
 |
Suspended
|
|
Join Date: May 2003
Location: Ottawa
Posts: 2,300
|
|
Quote:
Originally Posted by PunchT37
A person in the mountains says he can run 10.5 with iron heads and pump gas.
|
Hughe Engines.
Quote:
Altitude. As it gets higher, the cylinder pressure drops. This starts to really affect cylinder pressure around 1200’ – 1500’ altitude, and we have some racers @ 6000’. And it really hurts them.
Now you know why no one wants to talk about cylinder pressure. It is not a subject that is easy or fun to discuss or understand. Getting your local engine builder or some mail order shop to discuss it with you is impossible. What frightens many customers is when we tell them they need 12:1 or 13:1 compression and want to use 92 octane with their combination. They never heard of such things. That is because the people they are talking to don’t understand about cylinder pressure. We have customers running over 14:1 on 91 octane. They are at 6000’ altitude, aluminum heads and a BIG cam.
|
|