I hear so many people asking what size turbo should i get for my application etc etc sooooo much. So here is a little help on choosing a turbo that is going to be able to handle what your HP goals are.. This can get a little confusing but i will try my best to make it as easy as possible.. This is the way i was taught.. Please correct me if i am wrong in any sense..


Ok say you want to make 500hp and there is 10 lb/min per 100hp.. So at 500hp you would have 50 lb/min.. Now atmosphere is roughly 14.7.. Now say you want to run 18lbs of boost.. You take 18.0+atmosphere which is 14.7 which equals 32.7.. Then you divide 32.7 by atmosphere again which would equal out to 2.22 bars. SO then you go to the comp map sheetz and see where you fall into place.. The left line on map is your surge line and the right side is your choke line.. You want to fall in the middle of the island to be safe.. Here is an example of what i mean..





Hope this helps people better choose and understand there turbo selection..

Here is a link for tons of turbo comp maps..

http://www.ztechz.net/id6.html

http://www.full-race.com/articles/bo...r-housing.html

 

great work!

 

Sorry in my second pic the red dot should b one square bellow where it is. The numbers on pressure side are pretty hard to see.. But u get my point. When I get to my computer ill fix that map...

 

Awesome post

 

Thanks guys..

 

When people are using this method, they should keep in mind that your equation uses CRANK hp, not whp right?

Anyway, this is a great resource! Bookmarked.

 

very nice explanation, thumbs up

 

Sticky!!!!