hey everybody, i hear all this about "my turbo puts out 8psi" or "my turbo puts out 12 but i can turn it up to 16"... i understand that it's the unit of power that your turbo puts out but what does it stand for? what does it do? and how do you adjust it?

 

PSI = pounds per square inch. it is how you measure air pressure. So the higher the psi the more air is being pressed into the engine. more air means more hp. You can raise the psi with a manual or electronic boost controller. and you can also remove the bcs restrictor
Im not sure but I think for every 1 psi increase you get 5 or 10 hp. Someone please correct me if i'm wrong. besides increasing PSI on the turbo you should inprove the flow of air into and out of the engine.

 

on the 14 b i know its 5 hp per pound

 

soooo if you have a 165 hp engine, and you slap an 8psi turbo on it you are only gonna increse a max of 80 hp?

 

normal pressure on the face of the earth is around 13.8. PSI is the measure of forced air over that measure. when you calculate out parasitic and regular drivetrain loss, everytime that you double the air pressure, or in other words, every 13.8 PSI of boost, you roughly double your HP. for instance, if you take a 100hp engine, and add 14psi, it will roughly give you 200hp. This is also why when you have a very powerful engine, like a dodge viper, even at low boost, youre getting huge gains.

this also works with a supercharger, but with a supercharger there is a great deal more parasitic loss, enough so that on a powerful engine, running a vortech sueprcharger, at lower boost levels, like 2.5 psi, the engine may dyno the same as it did prior to the dyno, which is why you have to beef up the internals to be able to accept more boost...

 

that's what i was lookin for. thank you... now another question, is boost something that has a limit? or does your engine provide the limit... what i mean by that is can you "turn" up a turbocharger to like 25 psi??? what is the max you can take one up to??? and what is the engine pressure level on something like that? and if you can't turn a turbo that high, is that why you get a twin turbo?? and theatretically speaking if you had enough room under yoru hood, could you put as many as you wanted?

 

umm...i have seen a video of a guy who took a turbocharger off of a tank, and bolted it to a supra engine, and at 80psi, the car turned into a fireball...the turbocharger itself is limited in how much "boost" it can produce due to the limited speed of the turbine...bigger turbos can create more boost.

the amount of boost is, in theory, endless, but it is more of a realistic thing. the more that the internals of the engine are beefed up the more boost that the engine can handle, but i think that the most boost i have seen a vehicle run was 35 psi, and that was on a roots style sueprcharger on a 68 GTO, and he was building about 2700hp...it was sick..to say the least.

twin turbos can work in two different ways.
1-each turbo unit feeds pressure into the engine independantly
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2-the engine exhaust feeds a smaller turbo, and the pressure created by that smaller turbo is actually what spins the turbine in a second, usually much larger turbocharger. a larger turbo requires more spool time, and in a twin turbo setup like this one, the smaller turbo being used first helps to reduce spool time, and with this one, you have forced air replacing the pressure of the exhaust to spin the turbo that is actually forcing air into the engine.

im sure that someone could put like 20 turbos, but it woudl become pointless, and another problem, turbos tend to capture heat, andthat is why built turbo cars pay close attention to the exhaust gas temperature and such, also hence the need for intercoolers and watercooled turbo units. the Chrysler ME-412 concept, which has been scraped, is actually a quad turbo setup, but they are not in sequence, as with the above mentioned second scenario.

 

can someone tell me how to remove the bcs restrictor on my 98 gst? i heard it will take the stock 8psi to about 12-13psi? Is this correct? Can I remove it without moding anything else or would that be like a big no-no?

 

that answer, i do not know...your GSt only boosts to 8psi?!

 

i've never heard of an exhaust turbo... how much would something like that run??? also you say that a larger turbine will produce more psi, the biggest turbine i've seen in pix is only about 2-3 inches in diamater... where do you get a larger turbine turbo?