Boost vs altitude

[bulldoggie]

Hello all..... so I just bought a turbo and Maxx ecu for my gen 3. I'm still in set up mode, and I started thinking.... I'm at 5000 + feet where I live. Can you increase the boost a small amount on a stock engine say to 5 or 6 psi instead of 4, to make up for the altitude? Isn't it already going to have less compression since the air is thinner and can't get as much into the cylinders? Or am I going off the rails with that idea?

 

[LC4CARL]

I think that's the magic of boost. On a modern system, set it and more or less, forget it. 10 psi at sea level is 10 psi on Pikes Peak.

That being said, my only turbo experience is from the Jurassic age...

 

[bulldoggie]

Thank you for the reply....I was trying to think if that would be the case or not...I guess as long as the turbo is big enough to fill the cylinders, you can still move enough less dense air to make it the same.

 

[KawabusaRex]

Keep an eye on the pressure ratio, it rises with the elevation...got to make sure the engine can handle it. Screenshots are from Garrett's boost advisor site:

300HP 1.3L 10500rpm 0ft elev:

300HP 1.3L 10500rpm 5Kft elev:

Turbocharging At Elevation

A naturally aspirated combustion engine will lose 3% of its power for every 1,000 ft of elevation gain. Add a Garrett turbocharger to minimize the loss

www.garrettmotion.com

 

[bulldoggie]

Right on..... thank you!

 

[michael parris heuberger]

Thank you for the reply....I was trying to think if that would be the case or not...I guess as long as the turbo is big enough to fill the cylinders, you can still move enough less dense air to make it the same.

Hi. Give Boost by Smith a call he is a sponsor here he can hook you up.

 

[bulldoggie]

Hello and thank you.... I am currently working with Greg on getting my bike set up.... he is fantastic and a wealth of info and has cleared up many things for me. But I appreciate your reply in pointing me the right direction.

 

[01smokes]

It takes about 3psi of boost to equal sea level @5500' from all my testing.

 

[LC4CARL]

Not familiar with pressure ratio. Interesting.