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Discussion Starter #1
Kind of a dumb question but how much will it hurt to run just one small section of 3" piping for a charge pipe?? It will only be 3" from the throttle body to where it goes down the hole where the factory air box sits then i will change to 2.5" the rest of the way to the intercooler. The only reason i ask is cuz a friend of mine gave me a chunk of what use to be a roll bar on his truck but it is the exact bend needed for that top charge pipe, ill post a pic of it soon just for the hell of it.... I know its ghetto but it saves me some money and some welding, but i dont wanna do it if its gonna make lag alot worse or anything.

Thanks alot.
 

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its not really going to hurt anything, as long as you don't get rust into your motor. If its regular old mild steel, you may end up having problems down the road...such as fucked up rings and possibly even valves (if rust got sucked into the motor.)

remember that charge piping size is even more important than exhaust size to a certain extent. 15psi in 2 inch piping isn't the same as 15 psi in 3 inch piping....it will flow a hell of a lot more CFM's
 

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Discussion Starter #3
Im not worried about rust, the pipe is aluminum. Im just worried about the bigger piping causing extra lag.
 

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well lets see...from the turbo through the intercooler...the speed will be "x"... but when that same air gets to the 3" pipe...the speed of the air will slow down because of the increase in volume. you could say that there would be more lag because it takes slightly a little more time than, say, if you had 2.5" all the way around... but then you add that when you first open the throttle... you're getting a chunk of 3" air... - i think you can see where our confusion sets in.

put shortly... you're going to have a pressure drop when it goes through the intercooler...and you're going to have another pressure drop when it hits the 3"... what would that do? but it's probably safe to say it's not going to change lag - ALOT... i think that's more affected by the hot side of the turbo. (although affected by the cold side as well....NOTHING compared to the hotside)
 
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