Useful info on intakes

[Gen1GT]

I thought this would be some good info for the NA section on intakes. It addresses the 'CAI vs SRI' debate. (Short ram all the way)

http://www.tprmag.com/issue/1/1_challenge_2.shtml

[akhilleus]

I think that data can be interepreted in many ways. Depending on manufacturer both CAI and short rams showed similar gains. However in terms of a short ram i still believe that pulling hot air form the engine compartment is a bad idea. Particularly on the FS which tends to get quite hot. I personally would never put a short ram on for this reason. Also by locating the intake in the fender the potential of a ram air/cold air feed is more realistic and u dont have to buy a CF hood with slots to get it.

[Gen1GT]

I think the gains from 'cold-air' are marginal at best. The flow restriction CAIs create aren't worth it, and you lose throttle response with the larger intake.

[Mr. Win]

I think the gains from 'cold-air' are marginal at best. The flow restriction CAIs create aren't worth it, and you lose throttle response with the larger intake.
tru tru i would say whatever fits your budget. The gains are so min. that it really doesnt matter other then sound short ram is crazy loud.

[hi-perf]

what car were those tests performed on?

[akhilleus]

The vehicles arent specified from what i saw. Also although there is maybe a minimal amount more restriction in a CAI compared to an SRI. However considering the dynamics i would think that it would have less impact on the vehicle when compared to exhaust bends and restrictions. Now on the 1st gen the SRI may be better but for the 3rd gen i think the CAI has the capacity to support more hp than a sri. outside cooler air is always better than underhood hot air.... and when u are talking a large difference in temp it really does make a difference.

[Gen1GT]

The vehicles arent specified from what i saw. Also although there is maybe a minimal amount more restriction in a CAI compared to an SRI. However considering the dynamics i would think that it would have less impact on the vehicle when compared to exhaust bends and restrictions. Now on the 1st gen the SRI may be better but for the 3rd gen i think the CAI has the capacity to support more hp than a sri. outside cooler air is always better than underhood hot air.... and when u are talking a large difference in temp it really does make a difference.
It's not as huge a difference as you think. By the time the air in the aluminum intake gets to the manifold, it's almost as hot as if it were taken from a short ram. Do you have CAI? If you do, go for a one hour flogging, then stop, open your hood and put your hand on the intake piping.

Not only that, intakes which cause a higher drop in pressure, affect power output more. CAI forces air to move faster(which is good for low RPM power), but at higher RPM, it can't move fast enough to keep up with the air demand of the engine, but you still have low pressure air coming in the intake. Read this, it explains better

http://www.neuspeed.com/faq/faq_view.asp?id=15&ltype=ns_import

Besides, just because you're bringing cold air in from the ground or fender, doesn't mean that by the time it gets to the intake port, it's cold enough to make a difference. If you were to put temperature probes right behind the injectors, you'd find that air temperatures MIGHT be 5 degrees colder than with a SRI. But the restriction it causes, you'd be down on power anyway. Maybe with phenolic spacers and a carbon fibre intake it would work. Maybe.

[akhilleus]

That article wasnt very conclusive. I mean the pressure drop from using a cai would more than be compensated for by the temp difference. And the fact that there is more accessible air outside of the vehicle than in the engine compartment and if u can feed air into the fender well so much the better. Many race cars also use CAI systems so the experience and science are there. Since the CAI piping shields the heat and the movement of the air reduces the amount of time it is exposed to the heat the heat sink factor is also reduced. Neuspeed did sell both systems as well, tehy also said that it depends on the application. I think the CAI is better on the 3rd gen...and its easier to make a CAi into a ram air.

[Gen1GT]

Only one way to know which is better for your application. The drag strip. Even the dyno can lie in this case, since moving air is a big factor. I'll bet that 9 times out of 10, the SRI is faster though......

[TXMazdaSpeeder]

from what i've read and based on my dyno numbers is to do the modified aem sri (filter located behind drivers headlight instea dof behind radiator), u dont get the throttle response loss os a larger intake, and ur alot less likely to hydrolock.


BTW: heres my dyno numbers

Mods: Resonator delete, Sparkco Wires, Bosch Plat +4 Plugs, Spintech Muffler, Throttle Body Bypass, AEM SRI (showing both installed as aem instructions and modified install numbers.

As done on a dynojet dynometer, Denton, TX 500-600 feet avove sea level.
Modified Install: 114.8whp/122.6 torque
Normal Install: 106.7whp/118.5 torque

[PhreakV]

by locating the intake in the fender the potential of a ram air/cold air feed is more realisticI've never understood this argument with the placement of the 3rd gens CAIs in a fender well. the air may not be as warm with the placement but the utter lack of airflow (unless you remove a fog light or modify the fake 'brake vents' (on a 3.5 MSP) would be the main cause of the lack of air pressure.

just to clear up the racing application of CAIs; they powdercoat the CAIs to deter the heat transfer, I've yet to see more than a couple people do this with the FS engine.

oh well, only a handful of proteges will ever see enough power to make a difference anyways.

SRI be-otch! :D

[TXMazdaSpeeder]

I've never understood this argument with the placement of the 3rd gens CAIs in a fender well. the air may not be as warm with the placement but the utter lack of airflow (unless you remove a fog light or modify the fake 'brake vents' (on a 3.5 MSP) would be the main cause of the lack of air pressure.

just to clear up the racing application of CAIs; they powdercoat the CAIs to deter the heat transfer, I've yet to see more than a couple people do this with the FS engine.

oh well, only a handful of proteges will ever see enough power to make a difference anyways.

SRI be-otch! :D
what about the undercar air vent from corksport that makes air flow up into the fender well?

[03P5]

Lack of air flow? Its a Cold Air Intake, not a RAM air, the gain is supposed to be from the air temp difference compared with an SRI, not whether is being fed cold air at any high rate. If it couldn't draw cold air fast enough in the fender, it would create a vaccum in there, and do you really think that's happening?

The car they used is a 2002 Civic EX. It shows that on the AEM website. Until there's an article based on the Protege's available designs you'll never know, especially with how fast our ECU's adapt to new air/fuel ratios etc. compared to the Civics.

[MSP#735]

very interesting article and info!!! so lol, SRI or CAI?? Is it a matter of opinion or performance????? Im in the market for a CAI now (badly) and im tryin to save money at the same time so BIG question......CAI or SRI (2003.5 MSP)

MSP#735

PS: this was performed on a 1999 Honda Civic Si with 37,000

[TXMazdaSpeeder]

very interesting article and info!!! so lol, SRI or CAI?? Is it a matter of opinion or performance????? Im in the market for a CAI now (badly) and im tryin to save money at the same time so BIG question......CAI or SRI (2003.5 MSP)

MSP#735
AEM SRI, modified mounting posisition, of course i have yet to see a dyno chart of a mp3 with simliar mods and injen cai

[MSP#735]

but see i am turboed....our SMIC sucks balls......therefore resulting in needing a CAI..... maybe (dunno)

[TXMazdaSpeeder]

but see i am turboed....our SMIC sucks balls......therefore resulting in needing a CAI..... maybe (dunno)
cai, hard pipes, fmic (cool)

[MSP#735]

dont have that kind of money!!

[PhreakV]

If it couldn't draw cold air fast enough in the fender, it would create a vaccum in there, and do you really think that's happening?not a vaccum in the atmospheric-science/physics sense, but it (and all other designs) is acting much like the vaccum in your house. the CAI pulls in air from the box your putting it into, the chamber down there is pretty well restricted/sealed up (hence the extremely small possibility of getting wet from rain/the elements (not saying this as a negative, just pointing out that it is sheltered from outside)) and so it only follows logic that air will follow the easiest path. the easiest path in this case is from above (where the CAI piping enters from the engine bay) and while the air is not very close to the manifold and exhaust piping its still from the engine bay... that's why the CAI doesn't show miraculous gains from this freezing air that its sucking in. it is able to overcome the increased distance that the air must travel but otherwise you get the same effect (read: gains) from either the SRI or the CAI. now if you were to get serious with it and take out the fog light to vent outside air directly to the filter then you'd see better gains (of course, you could also take out the driver's headlight and funnel outside air to a SRI).

whatever, intake debates will rage until a scientific god buys a protege and decides to make it a life's work...

[PhreakV]

dont have that kind of money!!
then focus on a FMIC or hard pipes (after one get the other) and then get an intake. you can modify (reversible for your convenience) your stock box and get close to the same gains as an intake on a stock MSP.

[MSP#735]

AAAAAAHHHHHHHHH! what to do!

[akhilleus]

Now what if u have sealed the apeture where the CAI feeds into the fender well and have also routed a hose to feed air into the compartment... I would think that would more or less ensure colder air. Another things is that hot air rises and cold air falls so having the filter lower to the ground would mean: first the air it is pulling is colder than most ambient air, and also any air that enters the fender well will be colder than the air inside the engine compartment. And i also think a CAI looks better soo :p