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JRyan · 12-19-2009, 12:04 AM

Let me start this by saying my verdict is still out if I'm for or against the index change. On one hand it benefits my superstocker as it allows me a little more breathing room and on the other hand it makes it a little tougher on my low budget stocker I've been putting together. So with that being said.

I love it whenever the AHFS gets discussed with altitude corrections and the lack of understanding most have with how the altitude correction actually works. By the way we've said for the last ten years the altitude correction factors are probably off about 10% because you can somewhat cheat the car into going faster by making changes to compensate. When we used to run at Denver alot we'd change camshafts, converter, rear gear, transmission, tires, and jetting to run fast. So everyone that thinks it's so easy to just go to the mountain and go fast I'd invite you to load up in July and give it a shot.

Someone mentioned 1.25 under at altitude is the same as sea level. This statement is absolutely false. I'll give you an example. Oahe Speedway in Pierre SD is 1700' above sea level in SS/NA I get .24 correction. So my index there is now a 12.39 with my old index being a 12.69. This year at the National Open I went an actual 11.238. Under the new system this would be 1.152 that would equate to a 10.998. However, this is not what it factors to. That run is actually an 11.023. This is how records get figured at altitude. At Denver you lose close to a .10 at this speed. So lets say next year I run an 11.14 and reset the record. This would be 1.25 under should I automatically get HP even though the record is only going to be 1.23 under? So is 1.25 under at altitude still 1.25 under at sea level? According to NHRA's policy for setting records NO!

Also you can't use corrected altitude to figure factoring either. 1500' at Atco and 1500' in Pierre SD as an example are two completely different things. At one place you might get that air and it's cool and dense and the other it may be a little warmer and drier. The car isn't going to run the same nor is it necessarily going to take the same tune to run at either place.

My .02
Rick Ryan

12-19-2009, 12:04 AM	#66
JRyan Senior Member Join Date: Apr 2003 Location: Aberdeen SD Posts: 645 Likes: 30 Liked 112 Times in 31 Posts	Re: Index Change Let me start this by saying my verdict is still out if I'm for or against the index change. On one hand it benefits my superstocker as it allows me a little more breathing room and on the other hand it makes it a little tougher on my low budget stocker I've been putting together. So with that being said. I love it whenever the AHFS gets discussed with altitude corrections and the lack of understanding most have with how the altitude correction actually works. By the way we've said for the last ten years the altitude correction factors are probably off about 10% because you can somewhat cheat the car into going faster by making changes to compensate. When we used to run at Denver alot we'd change camshafts, converter, rear gear, transmission, tires, and jetting to run fast. So everyone that thinks it's so easy to just go to the mountain and go fast I'd invite you to load up in July and give it a shot. Someone mentioned 1.25 under at altitude is the same as sea level. This statement is absolutely false. I'll give you an example. Oahe Speedway in Pierre SD is 1700' above sea level in SS/NA I get .24 correction. So my index there is now a 12.39 with my old index being a 12.69. This year at the National Open I went an actual 11.238. Under the new system this would be 1.152 that would equate to a 10.998. However, this is not what it factors to. That run is actually an 11.023. This is how records get figured at altitude. At Denver you lose close to a .10 at this speed. So lets say next year I run an 11.14 and reset the record. This would be 1.25 under should I automatically get HP even though the record is only going to be 1.23 under? So is 1.25 under at altitude still 1.25 under at sea level? According to NHRA's policy for setting records NO! Also you can't use corrected altitude to figure factoring either. 1500' at Atco and 1500' in Pierre SD as an example are two completely different things. At one place you might get that air and it's cool and dense and the other it may be a little warmer and drier. The car isn't going to run the same nor is it necessarily going to take the same tune to run at either place. My .02 Rick Ryan