Factory air box with high flow drop in filter VS Open air cone filter

[AllenRPS13]

what do u guys think? which one is better? factory air box with high flow drop in filter or Open air cone filter? any idea?

[Silverbullet]

modify the factory air box, you'll get same HP gain, if not more if you make it into a cold air box.

[orion::S14]

The baffles in the factory airbox slow the airflow...I felt a small gain when I switched from a K&N drop-in filter (factory airbox, with most the front and bottom cut out) to a cone filter / MAF adapter. Picked up a tenth in the 1/4 mile, too...this way way back when my car was an auto, and only had a cone filter and a sh!tty exhaust.

I was running a heat sheild around the cone filter, though...

Food for thought...

- Brian

[alkemyst]

The Nissan airbox (at least an S14) is a little more extensive than most other cars....they were tuned to be ultra quiet at a compromise on power. It's a little hard to really 'drill' it out like a normal box because the thing takes up the front driver's 1/4 of the engine bay practically.

A cone filter too is probably giving up a little due to hot air invasion. The best setup is a new large as possible air box that seals the intake to the hood and sides then opens to the front and underneath with a cone filter and possibly a cold air extension. You lose some 'noise' but it makes for a better intake.

That said...we are more than likely talking a tenth or two at the most on average in the 1/4 mile.

Where you see the biggest improvement is stop and go in the heat....a little more throttle response.

I am just going to go forced induction...it cover's up so many little 'non-ideal' conditions ;)

[TurDz]

Picked up a tenth in the 1/4 mile, too...this way way back when my car was an auto, and only had a cone filter and a sh!tty exhaust.


do you run the 1/4 mile consistent enough to notice a difference such as a tenth? I know the 1/4 mile is one of the best ways to test gains, but a difference that small could come from any variable.

[orion::S14]

^^^ With an auto, it's hard to NOT be consistant.

Wait for the light, punch the gas, hold on for 16-17 seconds, hit the brakes. Easy, consistant.

I never went for a good reaction time, since it's not factored in...and the 60' timnes with an auto are pretty much the same every time.

- Brian

[AllenRPS13]

actually, i have a hks high flow filter with the factory air box, i make a air duct hose to go under the grill too, i think it will have better response than the cone filter since my car is automatic... do u guys agree?

[orion::S14]

With an auto, you really can't gain much anyway.

The TQ converter justr saps up so much power...and the gearing is not tall enough to make it fast.

Save some cash for a 5-speed swap, or just do suspension and brakes - Making power with an auto is wasted, b/c you will still have a +16 second car = no fun.

No point in making it loud (with I/H/E) if it's still SLOW.

I don't mean to be rude, just trying to save you a headache and an empty wallet.

- Brian

[AllenRPS13]

i also know that, anyway, thanks for yr suggestion, brian

[Chillaxed 240sx]

Well, 1/4 mile times are not the end all of performance racing ... there is autocross racing, too. You can't take an ungodly fast 1/4 mile car and take it on the autox track and expect to win, even if you have the skills of Dale Earnhardt. It's always a give a little to get a little situation whenever you put any modification on the car ... but since the weather is still cool, you should notice more hp than your stock box (some1 correct me if I am wrong).

[HyperTek]

but having a quick car with the most effiecent settings helps. If moding your stock air box doesnt throw a check engine light, your not getting any more air thru your maf sensor, just killing the sound dredning. The reason check engine lights come on with cone filters is becuase the maf is reading more air then what it is set for, and thinks that something is wrong. That should hint to you that you are getting more air thru it (less restrictive then the box)

If your check engine light does come on, solution is disconnecting battery for a full hour to reset ecu. Connect and drive for a few hundred miles. til that time, the computer recalibrates to whatever it is reading and everything is fine (so the computer thinks).

I have a K&N FIPK kit by the way. Excellent product. CARB Legal. Just doesnt use a metal intake tube like other systems.

[Chillaxed 240sx]

^ I did not know that. Learned something new today ... is it like that with the KA24E (89-90) motors, too?

[Var]

, even if you have the skills of Dale Earnhardt.


:rofl: :rofl: :rofl: :rofl: :rofl:



On topic...messing with your airbox doesnt give you worthwhile power on a stock motor. Technically it may give you .3hp or 1 hp or 3 hp.. but it's a waste of time. Get a header and/or a camshaft. That's the cheapest way you can get some real power and it will make your engine work better at high rpm's.

[Chillaxed 240sx]

You want to give me $300 for a Hotshot or Nismo header? You got $200 for a new performance cam you can spare? All right then ...

[orion::S14]

but having a quick car with the most effiecent settings helps. If moding your stock air box doesnt throw a check engine light, your not getting any more air thru your maf sensor, just killing the sound dredning. The reason check engine lights come on with cone filters is becuase the maf is reading more air then what it is set for, and thinks that something is wrong. That should hint to you that you are getting more air thru it (less restrictive then the box)...

Huh?

I've never seen that, with any S13 or S14.

If you get a CEL, then something else is wrong...

The ECU does not care how much the MAF reads...and will not throw a code if the readings are 5% higher than normal. Hell, I bolted on a turbo and maxed the MAF out (5.11 volts) on the first drive, and the ECU did not care.

- - - - -

And as for the auto-x comment...

True, but we're not talking about making 50rwhp here. Maybe 5rwhp.

And the reason I chose to use drag as a measuring stick is that it's a universal thing.

If I told you I put on an air filter and then won STX at the Solo II that weekend, what would that mean? Nothing.

You make a valid point, but it's not so relevant here.

(BTW, drag racing sucks...)

- Brian

[HyperTek]

then explain why majority of the time, when people install intakes, the check engine light comes on?... This is becuase the maf reads more air coming in.

[Var]

You want to give me $300 for a Hotshot or Nismo header? You got $200 for a new performance cam you can spare? All right then ...


no i dont. This thread isnt about you. WTF are you talking about. If you dont have a measly 500 dollars to put into your car you should stop modifying it right now and save up for tomorrow's lunch money.


edit:btw it costs more than 200 bucks for a cam.

[d4vech3n]

^^^ LOL

Thats a pretty harsh. I've been doing suspension mods to my car and haven't touched the engine besides for standard matanence. Would it be worthwhile to spend $300 on a cold air intake? That seems to be the first reasonable mod to do under the hood, Give me some feedback.

[orion::S14]

then explain why majority of the time, when people install intakes, the check engine light comes on?... This is becuase the maf reads more air coming in.

I think more often than not, people disconnect the IAT, or start the car with the MAF unplugged, or something...

But the MAF can read ANYTHING...higher or lower than normal...and the ECU does not care. ECU doesn't log MAF value and compare it with anything...it just reads the input and uses it to determine the fuel curve.

- Brian

[Var]

^^^ LOL

Thats a pretty harsh. I've been doing suspension mods to my car and haven't touched the engine besides for standard matanence. Would it be worthwhile to spend $300 on a cold air intake? That seems to be the first reasonable mod to do under the hood, Give me some feedback.


doesnt make any sense to me. Just get a filter and bend your own tubing . Shouldn't cost you more than 50 bucks. Spend the money on something you cant make, like a header or camshaft. That's my opinion.

I'm not being harsh just realistic. When you think about it if you cant afford a header, how can you afford a cold air intake? they are almost the same price.

[HyperTek]

Well one thing to consider, you pay more for street legal equipment, like AEM and Injen intakes... they come with carb e.o. decals and dyno-proven/tested designs.