Alright guys so i am going to be purchasing an is300 in the next few days and i am already looking ahead to going NA-T. I know a lot about these motors, but i keep looking at everyones setups and you guys all run regular intercoolers. What i am getting at here is why does no one run same side intercoolers, where the inlet and outlet are on the same side? With the over the top manifold it sounds ideal. To run piping across the engine bay cause more lag and seems silly. Is there no room for piping going down on the passenger side or something. what am i missing here...

 

Can it be done, sure, but there is hardly a lot of room... Two arguments against a same side intercooler - first being that your argument for one is moot to start... same side intercoolers are actually more efficient in terms of heat exchanging, as the air passes through the top or bottom, then follows that pass with another pass through the opposite... the down side is that there is a large drop in efficiency, as you are in effect squeezing the same amount of air through half the cross section of intercooler, but doing it twice essentially...

Here is an example for you:

Say you have two identical sized intercoolers, lets say a core size of 20 wide by 10 tall by 3 deep... The first intercooler is a simple side to side unit - the air flowing through it spreads out as much as possible, in this case, the entire cross section, about 30 square inches worth... It flows through this cross section for 20"... Now, the second unit is a same side intercooler - the way they work is that they flow through lets say the top for example, take a 180 degree turn and come back out the bottom... in this case, the cross section of the radiator is cut in half... now, we have 15 square inches worth of cross section, but the air has to pass through it for 40" worth, plus the complete u-turn... The second style will generally have a higher temperature drop, but, a higher pressure drop as well - in most cases, the extra pressure required will create extra heat, negating the higher temperature drop...

Now, for the second reason they aren't a good idea in our cars - there simply isn't room for for an outlet and an inlet on the same side... Here is a picture of my 28x8x3.5 bar/plate intercooler - it hangs down as far as possible without hanging below the lower bumper cover - I modified the crash bar and moved the power steering cooler and horns... I wanted to keep the crash bar as much as possible... even if it was mostly removed, there still wouldn't be room for a second inlet/outlet on the same side...

 

Thanks for the info