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Craig 930 RS Craig 930 RS is offline
Me like track days
Craig 930 RS's Avatar
Join Date: Sep 2003
Location: Kirkland, WA
Posts: 10,205
Thumbs up Intercooler 101 -

Overlook the fact that they are selling their own intercoolers........the information here is really good.

Helps cut throught the BS and internet-based misinformation.
Spend 1/2 hr and read through this stuff - esp if you are looking for an IC.

Stuff like this:

Most of the charge flows through the bottom 35% of core, with the top 65% causing detrimental pressure drop until high boost is reached. Worse again if other pipe is on the bottom too !!

Not perfect, but very good & very cost effective. Nowhere near as important to have diagonally opposite tanks like both designs on the left. Very small eddies & small uneven distribution across core window.

Detonation and intercoolers:
The most single deadly forced induction engine destroyer (apart from no oil) has two common names :- Detonation or when I did my time at college, Pre Ignition. My interpretation of these is when the spark plug ignites the intake charge, the flame front travels rapidly but smoothly, across the piston face to fill the combustion chamber with the exploding fuel charge & force the piston back down the bore. When something happens to destabilize the smooth travel of the flame front (wrong combustion chamber/piston dome shape, little/no squelch surface, sharp edges, hot heat range plugs, advanced timing, excessive compression, high boost, too low octane fuel,) one or more smaller fronts can start & these then collide, resulting in an early &/or more violent explosion, resulting in the knocking or pinging noise that sometimes can be heard from the top part of the engine. Interestingly, it is easier to hear a standard car/ute ( our terrible unleaded) pulling away from the lights up a hill, than it is a turbocharged car. I have to admit that I lost an engine of mine only this year, whilst testing on the open road (steepish hill) without hearing it. Radio on low & passenger reading data, I felt the engine nose over but by the time I clicked it & coasted to a stop, it was missing on one cylinder - side gone out of the top of the piston - expensive! That quick. Don't pass me off as a dickhead & it wont happen to you, be aware. The boost gauge decided to read at 60% of actual boost sometime just before the testing started, I adjusted it up thinking someone had changed it & it's that simple. The cooler the intake charge - the less chance you have of detonation ! I'm also positive that a consistently stable (air/water is supreme here) cooler intake charge also increases the life of headgasket, valve & seats, top bore-ring-ring land to a noticeable degree, whilst offering considerable more power potential. How important is intercooler selection now ????
- Craig 3.4L, SC heads, 964 cams, B&B headers, K27 HF ZC turbo, Ruf IC. WUR & RPM switch, IA fuel head, Zork, G50/50 5 speed. 438 RWHP / 413 RWTQ -
"930 is the wild slut you sleep with who tries to kill you every time you "get it on" - Quote by Gabe
Movie: 930 on the dyno
Old 12-28-2006, 08:16 PM
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