# question reguarding turbo and injector size **URL:** \ **Category:** NYSpeed Automotive\ **Created:** [July 16, 2006, 5:39pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678 "2006-07-16T17:39:35Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Tunerfreak](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tunerfreak/32/7427_2.png) [@Tunerfreak](https://forums.speedlife.net/u/Tunerfreak)\ **Post date:** [July 16, 2006, 5:39pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/1 "2006-07-16T17:39:35Z")
i was just wondering for u turbo guys if 48# injectors (not sure what that is converted to CC) would be good enough to drive around on running 7psi?? now i know u should not measure injector sizing with psi rating but im not goin to be beating on it either ---
**Author:** ![articzap](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/articzap/32/7361_2.png) [@articzap](https://forums.speedlife.net/u/articzap)\ **Post date:** [July 16, 2006, 5:46pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/2 "2006-07-16T17:46:15Z")
504 cc/Min …Sounds liek theyd be big enough to me. ---
**Author:** ![RuBiCaNT](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/rubicant/32/7622_2.png) [@RuBiCaNT](https://forums.speedlife.net/u/RuBiCaNT)\ **Post date:** [July 16, 2006, 5:54pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/3 "2006-07-16T17:54:10Z")
Slow down there… First off, you need to find out the maximum amount of air your turbo will be flowing @ 7psi by finding out the flow at the corresponding pressure ratio. Secondly, you have to find out how much your engine can flow at X RPM and X pressure ratio. You are better off finding out how much HP you want to make and using RC’s formula with that for your injectors. Use the following BSFC of .5 - .6. [http://www.rceng.com/technical.htm](http://www.rceng.com/technical.htm) ---
**Author:** ![Tunerfreak](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tunerfreak/32/7427_2.png) [@Tunerfreak](https://forums.speedlife.net/u/Tunerfreak)\ **Post date:** [July 16, 2006, 6:02pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/4 "2006-07-16T18:02:00Z")
yea i use that a while ago and im only lookin for 200 hp for now and it came up with somethin like 27-30#ish but i was not sure if i put everything in correctly ---
**Author:** ![RuBiCaNT](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/rubicant/32/7622_2.png) [@RuBiCaNT](https://forums.speedlife.net/u/RuBiCaNT)\ **Post date:** [July 16, 2006, 6:54pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/5 "2006-07-16T18:54:45Z")
> [@Tunerfreak](#): > > yea i use that a while ago and im only lookin for 200 hp for now and it came up with somethin like 27-30#ish but i was not sure if i put everything in correctly Aim a bit higher, you don’t want to be buying injectors again. I would tell you get something around 60lbs which still has the ability to idle really well but will give you around 350 - 400 crank HP with moderate duty cycles. ---
**Author:** ![focusinprogress](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/focusinprogress/32/7227_2.png) [@focusinprogress](https://forums.speedlife.net/u/focusinprogress)\ **Post date:** [July 16, 2006, 10:14pm UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/6 "2006-07-16T22:14:41Z")
^what he said, im close to max duty cycle on my 42# injectors at 13psi(oops…broken WG) ---
**Author:** ![Denton](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@Denton](https://forums.speedlife.net/u/Denton)\ **Post date:** [July 17, 2006, 4:33am UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/7 "2006-07-17T04:33:24Z")
there is also the question of fuel pressure and what kind of fuel system you have ---
**Author:** ![Tunerfreak](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/tunerfreak/32/7427_2.png) [@Tunerfreak](https://forums.speedlife.net/u/Tunerfreak)\ **Post date:** [July 17, 2006, 6:19am UTC](https://forums.speedlife.net/t/question-reguarding-turbo-and-injector-size/14678/8 "2006-07-17T06:19:27Z")
> [@Denton](#): > > there is also the question of fuel pressure and what kind of fuel system you have im using the stock fuel system but i am eventually goin to swap in a walbro 255 pump, im not sure that the stock fuel pressure is though off the top of my head thats somethin i would have to look up