Official "Pure" 91 octane evo thread - Page 18 - EvolutionM - Mitsubishi Lancer and Lancer Evolution Community

Notices
Evo Dyno Tuning and Results Discuss vendor and member dyno tuning techniques, results and graphs.
Sponsored by:
Sponsored by:

Official "Pure" 91 octane evo thread

Reply

 
 
 
Old Jul 22, 2018, 10:07 AM
  #256  
kaj
Evolved Member
iTrader: (58)
 
kaj's Avatar
 
Join Date: Mar 2006
Location: Fresno, CA
Posts: 8,763
Thanked 180 Times in 175 Posts
Those numbers are nice. I need to get me some S2s
kaj is offline  
Reply With Quote
The Following User Says Thank You to kaj For This Useful Post:
2006EvoIXer (Jul 24, 2018)
Old Aug 8, 2018, 08:38 AM
  #257  
Evolved Member
iTrader: (33)
 
vmrevo9's Avatar
 
Join Date: Oct 2006
Location: ABQ
Posts: 2,485
Thanked 3 Times in 3 Posts
Hey Guys I figure I can share my recent results now that I am on 91oct (Shell V-Power) and I am currently in Albuquerque, NM which is about 5300ft above sea level. One log is in 3rd and the second is in 4th. I will need to adjust my boost in 4th since I dont want it to spike above 26psi. This was more of a test hit to see how it looked.

I read a thread on here stating that for 5K ft altitude we can use 24.9 in barometric pressure so I used that in the SAE correction setting. If accurate, this altitude is definitely robbing me of power

Without SAE correction


with SAE selected and Barometric pressure set to 24.9


Let me know what you guys think
vmrevo9 is offline  
Reply With Quote
Old Aug 8, 2018, 11:25 AM
  #258  
kaj
Evolved Member
iTrader: (58)
 
kaj's Avatar
 
Join Date: Mar 2006
Location: Fresno, CA
Posts: 8,763
Thanked 180 Times in 175 Posts
Does elevation affect power for boosted cars, seeing how you're getting the same psi as you would at sea level?
​​​​​

Last edited by kaj; Aug 8, 2018 at 02:11 PM.
kaj is offline  
Reply With Quote
Old Aug 8, 2018, 12:24 PM
  #259  
EvoM Super Moderator
iTrader: (3)
 
MinusPrevious's Avatar
 
Join Date: May 2008
Location: So.Cal
Posts: 4,724
Thanked 580 Times in 553 Posts
Originally Posted by kaj View Post
Does elevation affect power for boosted cars, seeing how you're getting the same psi as you would at ground level?
​​​​​
Hey Jason. I think you mean "Sea Level" vs "Ground Level". Our friend in Albuquerque is certainly at ground level as well

Most notes shows a 3% loss per 1000ft change in elevation. So a rough estimate of running at 5000ft would be a 15% loss (maybe our turbo cars reduce that 3% margin a bit?)

MinusPrevious is offline  
Reply With Quote
Old Aug 8, 2018, 02:15 PM
  #260  
kaj
Evolved Member
iTrader: (58)
 
kaj's Avatar
 
Join Date: Mar 2006
Location: Fresno, CA
Posts: 8,763
Thanked 180 Times in 175 Posts
Originally Posted by MinusPrevious View Post
Hey Jason. I think you mean "Sea Level" vs "Ground Level". Our friend in Albuquerque is certainly at ground level as well

Most notes shows a 3% loss per 1000ft change in elevation. So a rough estimate of running at 5000ft would be a 15% loss (maybe our turbo cars reduce that 3% margin a bit?)

Fixed. I hate posting from my phone.

3% isn't much and makes sense for an N/A car, seeing how it's limited to sucking air at the density avail. But our cars compress the air to a certain psi, no matter how thin or thick the air is. I could see the turbo having to work 3% harder, though.
I'm just thinking out loud and could be 100% off
kaj is offline  
Reply With Quote
Old Aug 8, 2018, 02:55 PM
  #261  
Evolving Member
 
Join Date: Nov 2014
Location: Cyprus
Posts: 348
Thanks: 0
Thanked 11 Times in 11 Posts
On higher altitude things are not only affected by the composition of the atmospheric air, the lower percentage of oxygen, and the lower density, all which make the air move at a lower speed and in regards to combustion engines either internal or external, not being able to burn as much fuel as in lower altitude, but it is also down to the specific setup of a car or bike. On a turbocharged setup, i.e the 4g63t, it depends on the volumetric efficiency of the engine and the turbocharger used. The smaller the turbocharger the more effort it will need to put in to reach intented boost threshold, thus the more it will heat up the compressed air and thus even less oxygen will enter the combustion chamber. So loses could vary from 2-3% to 6-7% and even higher if there is a lake around and elevated water (hydrogen) particles exist in the air composition taking the place of oxygen ones.






Marios

Last edited by Evo8cy; Aug 8, 2018 at 03:02 PM. Reason: typo
Evo8cy is offline  
Reply With Quote
Old Aug 8, 2018, 05:04 PM
  #262  
Evolved Member
iTrader: (33)
 
vmrevo9's Avatar
 
Join Date: Oct 2006
Location: ABQ
Posts: 2,485
Thanked 3 Times in 3 Posts
This is all new to me since I have always been at sea level until now. Comparing what my wastegate duty cycle is set to now which is spiking to 26psi in 3rd at sea level it would have made about 29psi. I have also made sure to adjust the formula in evoscan to account for the altitude so hopefully the boost numbers are accurate. I do want to take the car to a dyno and see what happens. But I guess for now I am happy the car feels ok and no knock on 91oct.
vmrevo9 is offline  
Reply With Quote
 
 
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
2006EvoIXer
Evo Dyno Tuning and Results
335
Jul 21, 2018 03:36 PM
getsideways
Evo Dyno Tuning and Results
1712
Nov 2, 2016 01:40 AM
Boosted Tuning
Drag Racing
35
Apr 25, 2016 09:36 AM
rivalbro
Evo X General
1
Mar 30, 2016 06:16 AM


Thread Tools
Search this Thread
Quick Reply: Official "Pure" 91 octane evo thread


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.