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View Full Version : CAI or SHORT ram intake?



kelviN
07-08-2006, 08:05 PM
which is better for everyday driving?

advantages n disadvantages of each?

dsp26
07-08-2006, 08:15 PM
to answer your question... short ram

http://forum.pulsar.org.au/showpost.php?p=817663&postcount=1
that was tested on an SR20... it MAY not apply to your car but all internal combustion engines work the same so take it how you want until someone tests this on a Honda for it to be 100% credible...

***EDIT***
however, a CAI is technically MORE legal than a WAI setup as the pod won't be in the engine bay.

Reasons POD are illegal (legal defense with use of heat shield is negligible to the EPA):
- Could catch on fire ESPECIALLY if its oiled WHEN the car backfires up the intake.
- Excessive induction noise
- modified Emmisions resulting from hot engine air going in as well as the possible changing of the actual intake pipe.

The ^^^ first one does happen... i've had it happen to my hand while i was spraying throttle body cleaner in there... imagine what happens if you have fuel/ignition problems.... especially in summer....

Vinnie
07-08-2006, 10:45 PM
a properly done cai will always outperform a short ram. this is beacuse the cai situates the air filter outside the engine bay which equals cooler air which equals more efficiency etc. but the extra money involved tho is really just for the extra piping needed... and with proper heat shielding and protection (this is essential for safety and to keep it shielded from the hot air in the engine bay) there shood be no risk of the pod catching fire and apparently wen vtec kicks in it gives a great induction noise :) be aware tho that if u get a short ram and it sucks in hot air it can actually decrease performance :( properly ducted tho (access to fresh, cold air) either shood give a slight increase in power and give a better induction sound :D depending on ur budget, aem and injen are 2 reputable companies that im pretty sure do short rams and full cai's for ur car but gud luck with wateva u decide to go with neway :D

revNhevN
07-08-2006, 11:23 PM
cai. colder air = more power. i had a pod on my stock intake and it did nothing. now i got a cai with the same pod and i felt the diff straight away.

dsp26
08-08-2006, 01:05 AM
A WAI will be less restrictive due to less length and amount of bends in the pipe. However, you are pulling air from the warm engine bay. This is where a CAI comes in, cold air=dense air=more O2=more power. This is why dyno testing shows the results they do. However, there is one thing that needs to be taken into consideration, when the car is actually moving the air in the engine bay is not just sitting around getting hot, the intake temperature starts to drop. There is a great thread on an Altima forum where a guy actually put a digital thermometer in the intake to get readings. He tested a CAI, WAI, and a WAI with a tube feeding outside air to it(this is the type I find works the best). What he found was that the CAI stayed the most consistently cool, where as the WAI would get heat soaked at low speeds and at idle. However, when moving the WAI with the feeding tube would quickly drop to the same temperature as the CAI. Even the WAI by itself, got within 5°F of the CAI, but it took a bit longer. So what that info suggests is that even the WAI, while moving, ingests nearly the same temperature air as a CAI, and does it in a far less restrictive path. From what I have seen, the only disadvantage to running a WAI is heat soak, which believe me, sucks on a hot day in traffic. But adding a feeder tube to bring outside air to the WAI, pretty much solves the problem. The benefit to running a CAI would be the consistency, and a tad bit more midrange power(havn't figured this one out yet).

there is a reason alot of people on here suggest getting a a high flow replacement panel filter.

"arse dyno's" don't tell much.

a CAI is useless in summer.... low end bog from extended path with extra bends as well as hot air. A true CAI consists of the following items:

- Aluminium pipe (less heat transfer despite how hot it gets)
- Heat wrap around pipe
- Thermo spacers
- Bypass valve


also for those of you who switched to a CAI... its not the CAI itself that gave you the arse noticable gain, it's the resulting metal induction pipe that you would have had to get fabricated. get a straight metal one fabricated to stock specs leading into the stock box and you will have your biggest gain there. Factory induction hoses are restrictive..... especially the "ribs"

i personally dynoed ~4wkw gain from just changing to an aluminium pipe over stock induction hose as well as AFR leaning from 13.8 to 14.3:1 which is testament of the extra airflow... i didnt bother measuring AFM voltage at that point.....

SHIFTY
08-08-2006, 02:26 PM
Get a CAI, 110 % better.... ( no defects [if done correctly] , and will actually imoprove performance )

saxman
08-08-2006, 04:28 PM
dsp26... you're completely disregarding some features of a well designed cai... proper intake lengths allow you take advantage of valve reversion, and can be tuned to add extra power at certain rpms(why AEM cai's always make a nice bump in power in the mid range, etc). This is the EXACT same concept as tuning the intake runner lenghts on an intake manifold or velocity stacks for carbs/itbs. Adding a bypass valve to the intake actually cancels out this design feature, which is why most proper cai's DO NOT have one... unless as an optional add on.

Ever wonder why an AEM V2 cai makes more power than an AEM V1, at least at certain rpm ranges? They use the same filter, draw air from the same place, are routed past the same engine components, etc, but the V2 is designed in such away to take greater advantage of the harmonics of the intake pipe.



Between a short ram or a cai, it's really a toss up... CAI for more power, SRI for better throttle response

this is why you found slightly faster 5-60 times... the slightly better throttle response gave you a slight advantage for that kind of testing over the extra power from a cai that you would have noticed over a longer distance/on a dyno

dsp26
08-08-2006, 06:59 PM
^^^yeah i understand what your saying and similar thing goes for extractors for "scavenging effect" which is kinda the opposite.

i'm not going to argue with you either in regards to the V2 AEM intakes as i've seen them and are definately of high quality especially since their seamless and their angle-ing aren't that sharp.

my argument was based more towards exhaust shop fabrication quality as they use premade mandrel bends and weld together some pipe which ARE NOT "tuned length" obviously as you have already established. unlike AEM who stare at engine bays and use CAD software to calculate airflow, an exhaust shop will take a 1min look at your bay and fabricate the most accessible path... but also because of the welding, the inside of the pipes will have blobs where they were welded and the same thing goes for any welds on an exhaust sytem... it becomes an airflow bottleneck also similar to the ribbed factory rubber intakes.

your right on the money with AEM and their CAI:thumbsup: :D

however considering the price of just the intake, i'm pretty sure the majority of people who discuss advantages between CAI/WAI are talking about exhaust shop quality which costs AU$100-$200 to fabricate

saxman
08-08-2006, 07:50 PM
even without precise calculations, however, there are gains to be had with the longer intake paths... it may not be as precise or effective, but it still works.


I don't have any any experience with the exhaust shop quality cai's as you put it, however, so I can't really comment on that

CUL8R
09-08-2006, 08:59 PM
http://www.ozhonda.com/forum/showthread.php?t=42865