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Rb25 N/a Position Of Cai

Brendonams

By Brendonams,
in Engines & Forced Induction

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Brendonams Enthusiast

Brendonams

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Posted

Sorry to be a stain and make so many threads but I wonder a lot and I get asked questions, "Why aren't you doing this", "Wouldn't this be more economical/powerful". My question is why is the CAI placed behind the front headlight, shouldn't it be placed in a clear line of air rushing past the vehicle. An idea thrown at me was creating a metal box around the CAI and placing in the direct airflow near the body kit somewhere or putting a small hoodscoop on to provide more air rush to the CAI. I'm sorry if my words of description are silly but i've been asked by others around this topic.

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https://www.sau.com.au/forums/topic/387406-rb25-na-position-of-cai/
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farch Collaborator

farch

Posted
Posted

there's no outright correct way to do a CAI, behind the headlight is just usually the cheapest because that's where most factory air-box's are. A good CAI needs to be in a position where gets can get descent airflow and cold ram air. This can even be achieved with a rear facing intake like in a induction hood, which makes use of the air piling up on the windshield creating positive pressure. which is how the old school NASCAR's use to run, when they used factory car's like the camaro back in the 60's and apparently was good for 15-20hp when you were above 150km/h. but that is not as efficient as the front of the vehicle.

the power increase will never be great but the main reason you should do a cold air intake is so the engine doesn't get hot engine bay air and increase the likely-hood of pinging and such. especially with turbo cars because the act of compression of the turbo's increases the air temp, and this is compounded when the air is hot to start with, just compare driving your car in summer and winter.

but mainly just give the engine cold air who really cares where it comes from.

Brendonams Enthusiast

Brendonams

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Posted (edited)

Ah okay, this may be taking it off topic a bit because the topic has been answered quite simply, I have read many threads on turboing a N/A, but can I get someone clearly here to right

All out price:

Needed parts:

Wanted parts:

I just want a round about idea, I am sitting on not much money at the moment but I just want to know prices and pieces needed clearly. Also is it worth looking into supercharging a RB25DE? brother wanted to know because he thought it may be more simple then turboing it, but in threads i've read it's harder.

Thank you very much

Edited by Brendonams
StevenCJR31 Veteran

StevenCJR31

Posted
Posted

Yeah i've seen on ebay half cut skylines for a RB25DET for 3k, what do you think about them?

yep, the half cut could be the way to go . . you then have a motor designed for boost and (if fitted by a mechanic) a warranty. . . . do your maths first , as others will tell you, its cheaper to buy a turbo powered car in the first place . . . i paid 3k for my 32GTS-t with mildly modded RB20DET, quick enough to get you into trouble real easy

mad082 Grand Master

mad082

Posted
Posted

Blowers are legal

yeah, no.

as for CAI's, don't bother spending too much money on it as the gains are minimal (mostly in the drivers head). on a modern car that already has a bit of a CAI from factory, the gains are only a matter of a few kws. in a lot of cases i wouldn't be suprised if there is no gains.

Brendonams Enthusiast

Brendonams

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Posted

Not in Tassie (Hole) yet ;p, I mean they're bringing in laws soon so we "Catch up" with the rest of Australia but still atm you can drive forced induction cars no HP limits, v8's there are actually no limits for power.

Brendonams Enthusiast

Brendonams

Posted
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Haha I'm only 16 and it was kind of my first car xD, trust me wont be the end to my skyline family in the future I will (Hopefully if not dead) be driving a forced induction with a turbo loud enough to scare any cat from the road .

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