Guide: DIY charge-air water cooler build (intercooling)

So, it's all to do with flow. That's the reasoning behind it all. I will get my ruler tomorrow.

 

Corky did mention about flow area increased, but didnt say the normal way had higher losses.

2nd paragraph 1st page, says most breaker/oem coolers will have water through tubes due to size.

Area measurement will tell all.

 

Good thread, interesting reading to be had, cheers lads

Great job on Diy-ing by the way !

 

Ok, I got the digi calipers out and measured each of the tubes to work out the total areas for std and reversed flow for my core.

First up the way I'm running the boost, in std flow through the extrudes, the core is Low density this way, see pic below. The cross sectional area is 8.184inch2 and for 230bhp I require 8.05inch2 so I'm just over the minimum limit.

Running in reverse as, the core is high density with twice as many vanes. The cross sectional area is 25.2inch2 and for 230bhp I require a minimum of 13.8inch2.

Running reverse is less efficient as per C. Corky says with the extra vane density affecting the pressure drop so I will continue to run it in the std way with the more efficient extruded tubes. It also means the boosted air is in the cooling tubes formuch longer allowing greater copling to take place. If I do want more BHP I will have to upgrade or remake my charge-air cooler.

I will add more info to the opening post about core area and selection so others can work out what size core they need.


Pics of core to follow.

Std boosted path, low density core.



Reversed ambient air path, high density core note double number of vanes.

 

Not the extract from the book quotes hp per inch2, if this book is American it possibly refers to WheelHP and would therefore give me an even greater margin if this is the case, however, I have assumed it to be FlywheelHP to be on the safe side.

 

How long is the core? Is it less 10"?

 

It is 8inch long so the latter of the two described in the article is best if the cross sectional area is big enough, which it just is. (ie the way I am running it).