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Intercooler - will inlet/outlet size matter??
pewe - 23/1/17 at 06:30 PM

I'm determined to fit the bigger injectors and intercooler which I've had on the shelf for ages onto the supercharged hairdressers.
I bought a Pajero i/cooler from another owner having been told it would be OK.
My main concern is the inlet/outlet diameter on the i/c steps down quite a lot (45mm diam v 75mm on the s/c and plenium).
Does anyone know if this will be too restrictive or is pressure pressure?
S/c is an M45 and i/c measures 200mm high x 360 wide x 60 deep.
Any thoughts/suggestions gratefully received.
TIA.
Cheers, Pewe10


coyoteboy - 23/1/17 at 10:17 PM

It's less important than a naturally aspirated but it will still introduce losses if it's too small. Depends on the power you're running. Happily pass 350+HP through a boosted 58mm throttle body. You don't want to have many changes in diameter, each change offers chances for losses and turbulence, but if you assumed you had 45 from end to end it would be only slightly worse than, say, 50mm. 75 is a LARGE diameter for an intake.


jambojeef - 24/1/17 at 08:38 AM

Is it less important than for a NA though? In both NA and pressure charged engines a difference in pressure between the cylinder and the inlet tract causes flow? Curious as to why is matters less


coyoteboy - 24/1/17 at 09:37 PM

With a forced induction system you just dial up more boost to overcome the restriction (within reason). With a NA you can't dial up the atmosphere.