how dou figure bost +hp?

i mean if u ruuning 10lb of boost how much hp is that ?

depends on what you're pressurizing to 10psi!



10psi on a sewer pipe is a lot of water, but 10psi on a stir straw isnt

yea bout im talking about boost not water

how to translate boost to hp?

it all depends is what he is saying, i mean 10 psi on a built engine will make more power than 10 psi on a stock engine... we need more info on the engine

Someone told me that an average 4cyl. 1 psi=7hp, but on a bigger motor or on a rotary you should get more than that. I have heard you will get about 14hp out of 1psi. I don't know if that is accurate or what variables it is based on, but that is what I have heard.

it depends on the turbo/engine. the 917/30 ran about 14psi and 1100hp, but 14 psi on a stock turbo fc turbo motor will get you about 240

General rule of thumb is 10 PSI is 100 hp, which is 10hp per psi.

that is such BS



it all depends on the engine and turbo size.

Mike's analogy is correct. Replace the word water with air and it makes sense.

Who told you that? https://www.nopistons.com/forums/pub...1047683664.gif



10 psi on a stock turbo vs. 10 psi on a greddy T78. Now 20 psi on a stock turbo vs. 20 psi on a greddy T78. So they both will yield the same HP gain per psi?



HP gain per PSI is dependent upon turbo effeciency in that range of boost. Some turbo's are more effecient down low ...say 15psi and below. Some turbo's are more effecient at "high boost"....say 21 psi and above.

Yep, It's all about the volume or air and fuel @ that boost level that can get into and out of the combustions chamber in the amount of time it has to do so that will determine your HP as boost increases. As Jspecracer7 said, every turbo performs diffrently and this is why you have to choose a turbo that fits your application for the car.

lol I hope your joking big guy

What we DO know is 13b-TT=50k miles.

And absolutely no variation. https://www.nopistons.com/forums/pub...#>/biggrin.png

madz turdbo boostz = 10 madz qwick HP per PSIzzle







turdboo!!!!!!!

Yea, it's like this:



13b-TT= 50k Miles

13b-T=150k miles

13b=200k miles

12a=250k miles+



See a trend? :P

Not just the size of the turbine and it's efficiency range determine it either... a simple way of looking at it (very simplified) is that if you have a 1.5L motor running 15psi, you are packing 2x the air and fuel into it as if it was NA, so its kinda like running an NA 3L engine, minus the power loss required to drive the turbo. if you have a 2L engine running 15psi, thats still 2x the air and fuel, however now its like running a 4L engine. Still 15psi, but a greater volume of air and fuel, and thus more power per psi of boost. basically, nothing can be generalized with turbos, besides their effect on the longetivity of rotary engines as stated above.

and it does matter on the turbo,



for example on my audi a GT30R with an a/r ratio of .63 would put my audi at about 575 hp and having full boost around 4k rpm's compared to stock at like 200....



at the same time a GT30R with an a/r ratio of .82 would make somewhere around 600+ hp, but would not spool up untill much later maybe 5.5k rpm



both these turbo setups would run the same boost it all matters on the setup and the turbo sizing....

Yeah, but none compare to the almighty piston engine.

Yes I should have specified, I did mean stock turbo, but I tend to assume too much. My bad.

its all about volume, well that and the engine itself.



you cant just put a turbo in a car shell, connect the turbo to the trans, turn on the turbo with some switch an driveaway.



a turbo by itself makes no hp.



kevin.

You DO mean 13b-REW right phoenix??

brew? whos got beer?



kevin.

I DO! i do!

whos wrong whos right? im still confused , anyway i have a t2 street ported motor stock turbo.

what i did undertand is is all about the turbo size and how quick it spools im i wrong?

there`s a diferent amount of hp all the time the turbo is boosting or? no?

anyway i love turbo power

no turbo has a specific amount of horsepower production. how much power the turbo makes all depends on everything else, motor manifold design, exhaust size and restrictions....etc etc.



there's no way to be like "oh at 10psi that turbo is adding 132.456hp to your car"



kevin.

LIAR!

i like ceeeeereal.



kevin.

Would different ports affect how boost affects the car's hp levels too?

no but if theres a tornado on the ground, a poodle in the middle of the road, and a penguin walking it will.

you cant break it down like that. unless if you try running both motors n/a first i guess.



but i mean if you take a stock port at 10psi and compare it to a street port at 10psi....yea the street port should make more (depending on the turbo you're using and a bunch of other factors.) but the turbo itself you cant say is adding the power, unless like i said maybe you make both engines n/a first to set a baseline or something.



the port will affect the spool time considerably tho.



but anyway its not like you can say "hmm i have 150hp with 5 psi...so if i go to 10psi i'll have 200hp" it just doesnt work like that, everything depends on other factors.



kevin.

weird question, i should know it, but don't.



take stock port FD engine with say a T78, what is the rpm's where the turbo finally spools?



take same turbo, with same mods, and add streetport. would it spool later on??



does it all depend on the tuning/tuners settings? or would it be pretty much the same for both ports with the same turbo, etc?

thats a good question

i think it probably spool quiker at lower rpm

bout th efinal spool maybe affected

im just guessing here !!

If the exaust is ported right you can create more of a pop as the port opens that will cause the turbo to spool faster... It will also spool faster because more air in = more exaust out = faster spooling of the turbo = more air in.... It's an endless cycle I tell ya...



you should go rumage around in the single turbo forum and you should be able to dig up some good facts on turbo's and how they work and what works best on rotary's for different situations, ports etc...

Thanks. I know turbo's spool off of exhaust pressure, but just was not sure of a stock port vs. street port block.