View Poll Results: What does everyone think about this cold air intake?
Good
1
1.72%
Sucks
50
86.21%
Maybe
6
10.34%
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1
1.72%
Voters: 58. You may not vote on this poll
*** JDM Cold air intake ***
08-24-07, 12:40 PM
#28
Rx7 with Civic Si Engine!
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I've done a full tune up, I've replaced many gaskets, hoses, AC, seals, only thing i havnt done is the body and paint job, and will mostlikely keep the stock alloy rims and just paint it, so now im ready to put performance parts. I have 115k Miles on the engine, changed the fuel filter, air filter, oil filter, 02 sensor nology spark plug wires, with NGK spark plugs, Clutch is good, brakes has been replaced, trans, oil, coolant, all fluids had been replaced.. cant think of n e thing else, i have done plenty of things though, just cant get the rest of them out of my mind.
08-24-07, 12:42 PM
#30
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Originally Posted by kontakt
You will almost assuredly lose horsepower with that mod.
Ted is (always) right.
The stock air system before the throttle body is in no way shape or form the restriction that you want to remove. It is a well designed, high-enough flowing cold air intake itself.
Almost every system made loses horsepower through several ways.
1)Hot air. Either the system had no heat shield, or the heat shield doesn't seal.
1)Hot air. Either the system had no heat shield, or the heat shield doesn't seal.
2)Restriction. In the process of getting cold air to the custom air box through such typical means as the brake duct either requires a lot of cutting or a more restrictive setup than stock.
3)Heat Soak. The thick plastic stock intake does a very good job insulating the incoming air from engine bay temps. Any metal piping will heatsoak much more quickly and thoroughly.
But to the OP, there is no JDM intake. The JDM thing is said way to much and means almost nothing for most products that include the initials JDM.
08-24-07, 12:59 PM
#33
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Useless.
Might as weel swap in a TII for all the money you are planning on spending.
Might as weel swap in a TII for all the money you are planning on spending.
you don't ever want to polish the intake manifold after the secondary injectors, reason is due to the turbulance created on the walls with it being rough, keeps the fuel atomized instead of the fuel sticking to the walls.
08-24-07, 01:07 PM
#34
Caramelldansen
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If you must spend money on gaining power for an NA without doing a bridge/P-port you'd be best off deleting your pre-cat.
Either gut it (ghetto style) or get something like the Racing Beat pipe + presilencer combo.
It would be the easiest, most cost effective way to gain some more power from an NA.
08-24-07, 01:13 PM
#35
If you see that link, it look slike it's just a filter with a pipe, a hot air intake, if you would.
I think the point was that an open filter in the engine bay produces less horsepower than a stock airbox set-up, no matter which company made that filter.
I'm actually interested to see if that's true.
I think the point was that an open filter in the engine bay produces less horsepower than a stock airbox set-up, no matter which company made that filter.
I'm actually interested to see if that's true.
08-24-07, 01:19 PM
#36
MAzda has some competition manuals online somewhere and it gives you detailed measurements on how to build a CAI system with the snorkel in the front end and ducting to the filter. Look into that instead of ebay.
You're itchy to waste money but you're looking in the wrong direction
The hood scoop Idea works but you're using the incorrect type. I'd look into Z3-like fender vents and rather than mount them as vents you'd mount them backwards so the air goes right where the CAI and airbox are (like in the picture from natey) so you don't add a piece that will increase drag and not be very functional.
You're itchy to waste money but you're looking in the wrong direction
The hood scoop Idea works but you're using the incorrect type. I'd look into Z3-like fender vents and rather than mount them as vents you'd mount them backwards so the air goes right where the CAI and airbox are (like in the picture from natey) so you don't add a piece that will increase drag and not be very functional.
08-24-07, 01:33 PM
#37
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There is a Thread about custom making a CAI....just search tech posts...
The instalation doesn't require much cutting of your 7, just expanding your pre-existent hole for windshield wiper washer reservoir.
like some people mentioned before, the CAI would not give you much extra power unless you swap the exhaust system.
The instalation doesn't require much cutting of your 7, just expanding your pre-existent hole for windshield wiper washer reservoir.
like some people mentioned before, the CAI would not give you much extra power unless you swap the exhaust system.
08-24-07, 01:36 PM
#38
Rx7 with Civic Si Engine!
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I will be getting racing beat exhaust system, just wanna get an inside scoop about CAI.. due to the fact that, I cant find one for these 7's n e where. Thanks for all the info PEOPLE!!!
08-24-07, 01:46 PM
#39
is The Whoopieschnootz
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What mod? designing a low restriction cold air intake? Not a chance.
Smart guy, but I wouldn't go that far.
Actually there is restriction before the TB with the stock air box setup. The box its self is a good restriction. Loosing the box to my CAI for me gave me some high end.
There are heat sheilding products out there.
BS. you telling me straight pipe and a cone filter is more restrictive the the air box?
True, but it still heatsoaks. Again, you can buy heat shielding products.
But to the OP, there is no JDM intake. The JDM thing is said way to much and means almost nothing for most products that include the initials JDM.
Smart guy, but I wouldn't go that far.
Actually there is restriction before the TB with the stock air box setup. The box its self is a good restriction. Loosing the box to my CAI for me gave me some high end.
There are heat sheilding products out there.
BS. you telling me straight pipe and a cone filter is more restrictive the the air box?
True, but it still heatsoaks. Again, you can buy heat shielding products.
But to the OP, there is no JDM intake. The JDM thing is said way to much and means almost nothing for most products that include the initials JDM.
Maybe if you have already gotten rid of your AFM by going EMS and have a big exhaust and port job you might need a "CAI." If that was the case though, there's no way you'd have to ask.
The box is a restriction... just not to a stock ported rotary.
I wasn't saying that a ram air is more restrictive than stock. A ram air, however, sucks hot engine air. I am saying that the way 95% of people making CAI's get ambient air to their air box is more restrictive than the way mazda dit it.
Look I'm not trying to be a dick, but I've been researching this recently. Look it up, you can find dyno proven power losses going to a CAI.
08-24-07, 02:05 PM
#40
If you don't like the 15 dollar airbox idea, then you can (I can't believe no one's mentioned this) always make a 92-99 Prelude CAI fit. You'll have to do a little cutting, though. I stole this super professional P/S job from another thread....Thanks to whoever made it.
08-24-07, 02:29 PM
#41
Rx7 with Civic Si Engine!
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Nice, i like that Prelude CAI idea, So all i would have to do is cut that pipe, question? have u done this with yours? if so can u provide me pictures.. I might end up doing that..
Would this work... got it from MQTAutoparts Ebay listing
Would this work... got it from MQTAutoparts Ebay listing
Last edited by 13BGTU; 08-24-07 at 02:36 PM.
08-24-07, 02:34 PM
#42
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08-24-07, 02:57 PM
#43
Almost every system made loses horsepower through several ways.
1)Hot air. Either the system had no heat shield, or the heat shield doesn't seal.
2)Restriction. In the process of getting cold air to the custom air box through such typical means as the brake duct either requires a lot of cutting or a more restrictive setup than stock.
3)Heat Soak. The thick plastic stock intake does a very good job insulating the incoming air from engine bay temps. Any metal piping will heatsoak much more quickly and thoroughly.
A CAI can be made that will increase horsepower, but only the best one imaginable built properly. It will still only net like... 2hp.
1)Hot air. Either the system had no heat shield, or the heat shield doesn't seal.
2)Restriction. In the process of getting cold air to the custom air box through such typical means as the brake duct either requires a lot of cutting or a more restrictive setup than stock.
3)Heat Soak. The thick plastic stock intake does a very good job insulating the incoming air from engine bay temps. Any metal piping will heatsoak much more quickly and thoroughly.
A CAI can be made that will increase horsepower, but only the best one imaginable built properly. It will still only net like... 2hp.
2) Not an issue. The filter is far more restrictive.
3) Thin wide plastic is not a good heat shield. That's like using foil for armor then saying, "but it's steel!". In reality the poor heat transfer of air is your best protection. A thin sheet of aluminum is fine. Or, heck, even silver - the metal with the highest conductivity - would work. The key is to seal out the hot air really well (w/ rubber seals, etc.), and block heat that way. Heat transfer is very poor from air to surface and surface to air. So it doesn't matter that the surface to surface heat transfer is very good (even w/ stock plastic). You can cover your box with insulation like some people do, but it's not necessary.
Heck, if it was that easy to transfer heat from air to surfaces, intercoolers & radiators would be tiny and finless. Instead they have extremely large surface areas from hundreds of fins, for good convection. At the same time the thin fins conduct heat very poorly. Why? B/c they're 100 times more worried about convection than conduction. And even with several square feet of surface area from all those fins, even though they conduct heat 1,000 times better than a cold air box, people still upgrade them.
A) People find that a typical CAI increases power by ~5% compared to hot air. If you calculate the increase in air density you'll get about the same number. Again, it's not hard to keep the heat out, just seal out the hot air.
If I had to buy a CAI for $500 I'd say, "screw that". But a CAI is a cheap way to gain a little power. I just haven't gotten around to it yet. I've been busy with other things, plus it isn't on the top of my list for my car. In the meantime the P.O.'s cone intake is sapping a little power.
Last edited by ericgrau; 08-24-07 at 03:04 PM.
08-24-07, 03:08 PM
#46
Basically yeah. You still need to let in outside air, and block hot air under the hood with good seams and seals. Just do a search and see how other people made theirs. Most people put a box around the filter. They put an opening in the box which they connect to outside the car (or, usually, they stick it in a corner so that it has only 2 sides and a bottom, while the other sides are open to outside air). For some reason they like to leave the top side open, with rubber seals to keep air out. That way your hood becomes the "lid" on the box, and the box opens whenever you pop your hood.
08-24-07, 03:34 PM
#48
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Don't use the Prelude intake, your looking to gain .0000000000002 horsepower and have less low end. The Tii hood ram air scoop thing is out, unless you want to rev to 4500 at stop signs. Do reliability mods first! If your looking for performance stuff that means you're going to be pushing the car. Fix it before it breaks when you're "driving". Then save and save and save , because the only intake setup worth running an N/A is ITBs, which cost a lot and require a stand alone to tune. Your last resort is to convert to carbs, but then you risk fouling plugs if teh damn things aren't setup/ tuned right. Go individual, or go HOME!
08-24-07, 04:48 PM
#50
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Have you ever even looked at an AFM? Did you read all of what I wrote?
Maybe if you have already gotten rid of your AFM by going EMS and have a big exhaust and port job you might need a "CAI." If that was the case though, there's no way you'd have to ask.
The box is a restriction... just not to a stock ported rotary.
I wasn't saying that a ram air is more restrictive than stock. A ram air, however, sucks hot engine air.
I am saying that the way 95% of people making CAI's get ambient air to their air box is more restrictive than the way mazda dit it.
Don't use the Prelude intake, your looking to gain .0000000000002 horsepower and have less low end.
The Tii hood ram air scoop thing is out, unless you want to rev to 4500 at stop signs
Then save and save and save , because the only intake setup worth running an N/A is ITBs,