i heard so im doing some research that it is better to have smaller piping coming off ur turbo then go to bigger piping into ur intake mani...

now i think my ic kit is some ebay one but its complete and the piping coming off the turbo is 1 1/2 which i thought was wayyyyy too small...i am running it on my car and it fits good considering it is in an ef but will upgrading to 2 1/4 on the turbo side help that much....and i have 2 1/4 everywhere else...

 

just make the size the same, dont confuse yourself.

 

I've always wondered what the logic with the big pipe/small pipe thing was. Seems counter intuitive to me. Wouldn't the hot air coming out of the turbo be taking up relatively more space (requiring larger piping) and then after it's cooled it would take up less space (requiring smaller piping). Yet, the opposite is what is used. Maybe I'm looking at it wrong.

 

ok so I should just upgrade to 2 1/4?? Am I gonna see a difference?

 

no difference that you are going to really feel, most just run 2.25 or 2.5" and be done with it.

 

The reason a smaller diameter pipe is used on the hot side and a larger one on the cold side is to minimize the amount of lag in a system. Its the same reason that people shooting for 300whp shouldnt buy a PTE600 intercooler. Its more area that has to be filled with air (pressure) before that pressure can reach the throttle body and into the engine.

The other part has to do with fluid (air in this case) wanting to move from an area of high pressure to an area of low pressure; therefore, having a smaller pipe off the turbo (high pressure) and a larger pipe by the TB and engine (low pressure) will inherently make the air move from one area to the next. I hope my explanation makes sense.

 

yea I kinda understand what ur saying...very help thanks for the info...sense I already have the smaller pipe on there I think I'll just leave it...