# psi/lb **URL:** \ **Category:** PittSpeed Off Topic\ **Created:** [June 13, 2004, 7:31pm UTC](https://forums.speedlife.net/t/psi-lb/167112 "2004-06-13T19:31:08Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![ZackG](https://avatars.discourse-cdn.com/v4/letter/z/ce7236/32.png) [@ZackG](https://forums.speedlife.net/u/ZackG)\ **Post date:** [June 13, 2004, 7:31pm UTC](https://forums.speedlife.net/t/psi-lb/167112/1 "2004-06-13T19:31:08Z")
in a general application, how many hp do you think 1 lb of boost can create? ---
**Author:** ![Shaggy](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/shaggy/32/5945_2.png) [@Shaggy](https://forums.speedlife.net/u/Shaggy)\ **Post date:** [June 13, 2004, 7:45pm UTC](https://forums.speedlife.net/t/psi-lb/167112/2 "2004-06-13T19:45:40Z")
what out there creates just 1lb of boost? or did i read that wrong? ---
**Author:** ![ZackG](https://avatars.discourse-cdn.com/v4/letter/z/ce7236/32.png) [@ZackG](https://forums.speedlife.net/u/ZackG)\ **Post date:** [June 13, 2004, 7:51pm UTC](https://forums.speedlife.net/t/psi-lb/167112/3 "2004-06-13T19:51:27Z")
no like a general equation… like if you add 10psi of boost to a non turbo car, how much more hp would you create divided by 10. ---
**Author:** ![Shaggy](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/shaggy/32/5945_2.png) [@Shaggy](https://forums.speedlife.net/u/Shaggy)\ **Post date:** [June 13, 2004, 7:53pm UTC](https://forums.speedlife.net/t/psi-lb/167112/4 "2004-06-13T19:53:53Z")
it may differ from application to application. ---
**Author:** ![ZackG](https://avatars.discourse-cdn.com/v4/letter/z/ce7236/32.png) [@ZackG](https://forums.speedlife.net/u/ZackG)\ **Post date:** [June 13, 2004, 7:55pm UTC](https://forums.speedlife.net/t/psi-lb/167112/5 "2004-06-13T19:55:37Z")
yeah, thats why i said general rule of thumb ---
**Author:** ![Shaggy](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/shaggy/32/5945_2.png) [@Shaggy](https://forums.speedlife.net/u/Shaggy)\ **Post date:** [June 13, 2004, 8:00pm UTC](https://forums.speedlife.net/t/psi-lb/167112/6 "2004-06-13T20:00:38Z")
maybe here you’ll find it > **[How Turbochargers Work](https://auto.howstuffworks.com/turbo.htm)** > > When people talk about race cars or high-performance sports cars, the topic of turbochargers usually comes up. A turbo can significantly boost an engine's horsepower without increasing its weight. ---
**Author:** ![GNocide](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/gnocide/32/5947_2.png) [@GNocide](https://forums.speedlife.net/u/GNocide)\ **Post date:** [June 13, 2004, 8:02pm UTC](https://forums.speedlife.net/t/psi-lb/167112/7 "2004-06-13T20:02:11Z")
at sea level around 10, here around 7 id say and thats a good guess. ---
**Author:** ![Shaggy](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/shaggy/32/5945_2.png) [@Shaggy](https://forums.speedlife.net/u/Shaggy)\ **Post date:** [June 13, 2004, 8:03pm UTC](https://forums.speedlife.net/t/psi-lb/167112/8 "2004-06-13T20:03:28Z")
> **[HowStuffWorks - Learn How Everything Works!](https://www.howstuffworks.com/?parent=turbo.htm&url=http%3A%2F%2Fwww.turbofast.com.au%2Ftfcalc.html)** > > HowStuffWorks explains thousands of topics, ranging from the flu to black holes to conspiracy theories, with video and illustrations so you can learn how everything works. ---
**Author:** ![ZackG](https://avatars.discourse-cdn.com/v4/letter/z/ce7236/32.png) [@ZackG](https://forums.speedlife.net/u/ZackG)\ **Post date:** [June 13, 2004, 8:07pm UTC](https://forums.speedlife.net/t/psi-lb/167112/9 "2004-06-13T20:07:58Z")
alright, 5-15 is what i was guessing myself, my friend said 30… i told him to get the fuck out of here and he wasnt backing down from it. ---
**Author:** ![Darkstar](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@Darkstar](https://forums.speedlife.net/u/Darkstar)\ **Post date:** [June 14, 2004, 12:56am UTC](https://forums.speedlife.net/t/psi-lb/167112/10 "2004-06-14T00:56:19Z")
10 is a more realistic number. However, there are a bazillion other variables that are also in the equation, so any sort of generalization is really pointless. ---
**Author:** ![flyinglow57](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/flyinglow57/32/5978_2.png) [@flyinglow57](https://forums.speedlife.net/u/flyinglow57)\ **Post date:** [June 14, 2004, 6:35am UTC](https://forums.speedlife.net/t/psi-lb/167112/11 "2004-06-14T06:35:38Z")
isnt it said that if you add 14lbs of s/c boost it will double your horse power??? so if you add 1lb of s/c boost you would add 1/14 of your horse power. ---
**Author:** ![fshowcars](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/fshowcars/32/5937_2.png) [@fshowcars](https://forums.speedlife.net/u/fshowcars)\ **Post date:** [June 14, 2004, 6:39am UTC](https://forums.speedlife.net/t/psi-lb/167112/12 "2004-06-14T06:39:49Z")
no… just think about the science behind it… the whole point is that you are causing pressure in your intake mani where in a N/A car you are just hitting 0 vac… meaning yes, you are adding 1psi of pressure, but how much is 1psi. we’ll it’s 400 cfm in one turbo as opposed to another… my stock ko3 turbo is pushing 22lbs of boost… does that = 22psi of a t77… no. a S/C is run off a pulley that is being turned by the engine… so you are actually using HP to make HP… totally different than that of a turbo… so 1psi of what turbo = HP is the question… and that can simply be answered by reading a compressor graph of said turbo… ---
**Author:** ![GNocide](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/gnocide/32/5947_2.png) [@GNocide](https://forums.speedlife.net/u/GNocide)\ **Post date:** [June 14, 2004, 6:49am UTC](https://forums.speedlife.net/t/psi-lb/167112/13 "2004-06-14T06:49:25Z")
> [@flyinglow57](#): > > isnt it said that if you add 14lbs of s/c boost it will double your horse power??? > > so if you add 1lb of s/c boost you would add 1/14 of your horse power. no but it does double your compresion ratio ,8.5to1 becomes about 15to1 under boost. ---
**Author:** ![imported\_gearhead](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/imported_gearhead/32/5957_2.png) [@imported\_gearhead](https://forums.speedlife.net/u/imported_gearhead)\ **Post date:** [June 15, 2004, 1:48pm UTC](https://forums.speedlife.net/t/psi-lb/167112/14 "2004-06-15T13:48:31Z")
its ALL about volumetric efficency, it can never be calculated in a psi/hp basis.