AZdrifterS13

So i was thinking, and i thought about this, and i was wondering if i was wrong. Is boost boost, no matter what turbo? for example, is 15 lbs of boost out of a smaller t28 the same as 15 lbs of boost out of a massive t4? All the spool up characteristics and stuff aside, its the same right?? Or does the turbo make a difference? Just something i was thinking about...let me know if im right!!!

S13NismoStyle

Yeah boost is boost. And 15 psi out of a t28 is still 15 psi out of a t4, but the difference is VOLUME of air at that psi. The T4 is a much larger turbo and will provide a much larger volume of air at 15 psi than the smaller t28. So larger volume = more Air w/ same amount of boost = more hp. It would be like one of those small propane tanks that holds 150psi, and then one of those HUGE tanks that holds 150psi. Althought the psi is the same, the volume is MUCH different. I think that pretty much explains and and thats my understanding. If im wrong, some one please add on. thanks

2fast4y0u

not that s13nismo is wrong i just want to add to the fact

when u have a larger turbo like a t4 compared to a t28, you will reach 15 psi real wuick with a t28. with a t4 on lets say an sr motor it will take a little while. but once you hit 15psi on a t4 there is still plenty more boost to build if u have the gear/rpm's left

jspaeth

In general boost means nothing at all, only if you are comparing 2 identical turbos

Boost has to do with how pressurised the air is....

15 psi on a T25 and a T28 are the same PRESSURE, but the T28 flows more volume, so 15 psi on the 2 different turbos correspond to different VOLUMTETRIC AIRFLOW, which is ultimately what determines how much power your engine makes

AZdrifterS13

Oh i seeeeee. so i was wrong. I was getting mad cause i would read about cars that were running with the same boost, but had way different horsepower numbers.