Open Cone(Hot air intake) vs Cold Air Intake

[Schurkey]

Let's face it--virtually all cone-filter, "cold (or warm) air intakes" are sold based on bling, not performance.

 

So far, nobody's taken up my challenge to MEASURE THE VACUUM IN THE INTAKE SYSTEM to see if the OEM design is a power restriction. Done carefully, so that intake velocity does not screw up the accuracy of the vacuum test, this should be quite reliable. An alternative would be a dyno test under controlled conditions, which is to say NOT one done by the folks who are trying to sell the intake system.

[l67ss]

Maybe this will help...

 

[video=youtube;gCi2yo4UqPI]

 

something i noticed in the vid is tho a nissan had 2 hp more with factory box, it had a broader(read useable) power curve with the cone filter

[l67ss]

Not exactly. I don't run better on colder air. And my lung capacity is far less than an engine. The length of the intake tube is irrelevant to an engine. It inhales and exhales at the same time. The amount of vacuum created doesn't diminish with length.

 

thats like saying the amount of backpressure stays the same regardless of exhaust length

[Imp558]

I didn't notice anything with my foot going from my stock airbox to my fwi, but it sounds bitchin'

As for the vacuum test, that may be kind of fun if one of us had a vac gauge that we could stick into an IAT hole, we could measure several different intake/engine combos with the same gauge at the Sept meet.

 

EDIT: My stock airbox was cut wide open underneath, only enough plastic to hold the filter, and that I did notice with my foot when I did it.

[l67ss]

I didn't notice anything with my foot going from my stock airbox to my fwi, but it sounds bitchin'

As for the vacuum test, that may be kind of fun if one of us had a vac gauge that we could stick into an IAT hole, we could measure several different intake/engine combos with the same gauge at the Sept meet.

 

EDIT: My stock airbox was cut wide open underneath, only enough plastic to hold the filter, and that I did notice with my foot when I did it.

 

i noticed dif goin from stock airbox to k and n cone with airbox base, then to stock box total delete with cone

[Imp558]

i noticed dif goin from stock airbox to k and n cone with airbox base, then to stock box total delete with cone

 

Mine seemed to pull a lot harder, and that was still the L36, the L67 never saw a truly stock airbox in this car so I don't have a first hand baseline comparison with a supercharger. One thing that prompted my fwi endeavor was that hpt was showing me 80F on a 55F day, kind of curious to see what it says on the next 55F day. And the IAT really should be a point in this discussion btw, the air temp at the IAT says a lot about how rich or lean the engine runs. A friend of mine was getting 30ish mpg with a 5.3L that ran way too hot, turns out the IAT was messed up and reading 350*F! After it was replaced the truck ran richer and cooler, and his mileage went down the toilet where it belonged.

[GTPer]

I didn't notice anything with my foot going from my stock airbox to my fwi, but it sounds bitchin'

As for the vacuum test, that may be kind of fun if one of us had a vac gauge that we could stick into an IAT hole, we could measure several different intake/engine combos with the same gauge at the Sept meet.

 

EDIT: My stock airbox was cut wide open underneath, only enough plastic to hold the filter, and that I did notice with my foot when I did it.

So a fwi didn't make a difference in performance. But what about the other way around? Has anyone felt like they lose power from an open cone? Supposedley from more heat pulling timing? I've heard of that being possible but have not seen or heard of proof

[GTPer]

Maybe this will help...

 

[video=youtube;gCi2yo4UqPI]

Wouldn't the fact that the car they tested here was intercooled make a difference in IAT being such a small difference between an open cone and cold air intake? Because it was like less than 10 degrees of difference. Or am I off?

[Imp558]

So a fwi didn't make a difference in performance. But what about the other way around? Has anyone felt like they lose power from an open cone? Supposedley from more heat pulling timing? I've heard of that being possible but have not seen or heard of proof

 

I had a HAI essentially when I cut the box, that was a noticable improvement over stock. While I didn't notice a change going to my fwi, it had to have mede some difference, it's very streamlined and my fiter is enormous. It's hard to believe, given the variables; airflow restriction and IAT temp that it made absolutely no difference. Here's the thread:

http://www.w-body.com/showthread.php/80147-First-Gen-Low-Buck-Custom-Cold-Air-Intake

[rich_e777]

[video=youtube;-jbfz8I9sBE]

 

This is what my car sounds like. I love that whine. You will not gain any power with a CAI heck you may actually lose a HP or two, but if you want a whine then yes get a CAI. A 1997 and a 1999 GTP have the same HP and TQ figures the different air intake had no affect.

 

 

Car with stock air filter the whine is hardly noticeable[video=youtube;R2ZdQBDG83I]

.

 

How does that whine of a L67 compare to the power steering pump whine of a CS?:lol:

[94 olds vert]

The SC whine is 10x better than the annoying PSP whine on the CSC. Lol

[GTPer]

I think I'm probably just going to make a custom fwi. It may not make a big difference but it will still give me a better whine. Anyone know what size tubing connects to the throttle body? Or what a coupler be best to connect to the throttle body then the tubing attached to that?

[Galaxie500XL]

I suspect the sound is about the only reason to install a WAI...

 

Keep in mind, it's not just the volume of air--cooler air/denser air/more oxygen by volume...more oxidizer (oxygen), add a bit of additional fuel---theoretically should mean more power.

 

After all, the engine is a fixed displacement, and I've not seen many factory intake systems that seemed as if they were incapable of supplying more air than the engine demands, assuming that engine isn't extensively modified.

[Imp558]

I think I'm probably just going to make a custom fwi. It may not make a big difference but it will still give me a better whine. Anyone know what size tubing connects to the throttle body? Or what a coupler be best to connect to the throttle body then the tubing attached to that?

3 1/2" , There's a link in my thread to the 45* bent piece I bought on E-Bay, it was cheaper than what the local metal supply wanted for a straight piece.

[GTPer]

So Im guessing you made a custom intake? How do I get to that link?

[Imp558]

So Im guessing you made a custom intake? How do I get to that link?

 

http://www.w-body.com/showthread.php/80147-First-Gen-Low-Buck-Custom-Cold-Air-Intake

[GTPer]

So if I were to use 3.5 inch tubing what size coupler would I use to attach the tubing to the throttle body? And would a 3 or 3.5 inch inlet filter attach to 3.5 inch tubing?

[GTPer]

Okay so this is what I'm thinking so far: a 3.5 inch coupler connected to 3.5 inch tubing, and a 3 inch inlet K and N filter. Probably just get a hole drilled in the coupler for the IAT sensor. I'm just a little iffy on sizes though. I mean a 3 inch filter would clamp on to 3.5 inch tubing right? Any help would be greatly apppreciated

[Imp558]

Okay so this is what I'm thinking so far: a 3.5 inch coupler connected to 3.5 inch tubing, and a 3 inch inlet K and N filter. Probably just get a hole drilled in the coupler for the IAT sensor. I'm just a little iffy on sizes though. I mean a 3 inch filter would clamp on to 3.5 inch tubing right? Any help would be greatly apppreciated

 

No Dude, just read my thread, a second Gen rubber coupler has a broad range of movement and a 3 1/2" tube will fit and clamp into it just fine, the coupler will also give you an IAT hole in the right place. If you do have additional bends to make and were not able to get a bent piece of tubing 3 1/2" couplers in whatever degree bend would be what you want. Theoretically one could braze aluminium with a MAPP torch and the rods from the hardware store (works well for things like this but won't hold boost without leaking).

The K&N site has a good guide of filter dimensions and I outlined a simple method to put a 3.3" filter opening on a 3.5" tube in my thread. Here's the filter guide:

http://www.knfilters.com/search/universal.aspx

My filter was for chevy trailblazer trucks and is huge, about 120 sq in vs my factory which was about 60 sq in.

It's tough to get a 3.3" filter opening onto a 3.5" tube, 3" would never fit from what I saw and if you tapered the tube down that far you would suffer flow.

Edited August 29, 2014 by Imp558

[GTPer]

No Dude, just read my thread, a second Gen rubber coupler has a broad range of movement and a 3 1/2" tube will fit and clamp into it just fine, the coupler will also give you an IAT hole in the right place. If you do have additional bends to make and were not able to get a bent piece of tubing 3 1/2" couplers in whatever degree bend would be what you want. Theoretically one could braze aluminium with a MAPP torch and the rods from the hardware store (works well for things like this but won't hold boost without leaking).

The K&N site has a good guide of filter dimensions and I outlined a simple method to put a 3.3" filter opening on a 3.5" tube in my thread. Here's the filter guide:

http://www.knfilters.com/search/universal.aspx

My filter was for chevy trailblazer trucks and is huge, about 120 sq in vs my factory which was about 60 sq in.

It's tough to get a 3.3" filter opening onto a 3.5" tube, 3" would never fit from what I saw and if you tapered the tube down that far you would suffer flow.

Okay so would a 3.5 inch filter clamp onto 3.5 inch tubing without tapering anything? And where would I find the second gen coupler?

[Nas Escobar]

Not exactly. I don't run better on colder air. And my lung capacity is far less than an engine. The length of the intake tube is irrelevant to an engine. It inhales and exhales at the same time. The amount of vacuum created doesn't diminish with length.

 

You may not run better in a colder air climate, BUT you may run more eficient because you won't tire out quicker. Perhaps the whole straw thing doesn't apply, but you can't deny that if you're not heated up, you perform better. Think about when you work. When you start out working, are you more energized since you haven't been sweating or are you tired out because you're colder? Once you start sweating bullets and your body is hot, you don't want to work as hard as you did when you first started working.

 

Lets put it this way. Would you feel tired more quickly and breathe harder if you went out and ran on a humid 100F day or if you went out and ran on a 70F breezy day?

 

As far as all this goes though, the whole "cai/wai" thing is purely sound. You can make one using the stock box by simply getting a custom pipe done that removes the accordion, and removes all silencers. The 2 biggest restrictions on a car is the muffler and the silencer. If you seriously want more power, the easiest way to do so is to do the whole intake and exhaust system. You won't notice anything by simply doing a WAI or CAI because you have stock programming that limits air intake and you have the MAF that hinders you. Any car with a MAF doesn't benefit from a CAI without proper tuning. If a car inhales and exhales better, you will feel a minimal boost in performance, but that's it. Your powerband stays the same but the jump the engine has is better/more quicker.

 

If you're making a custom CAI, go ahead, but get yourself a Dynamax Turbo muffler (if you don't want exhaust sound but want efficient flow) and replace your resonator with a Cherry Bomb (better flowing). If you can, get high flow cats as well. Then you'll have something you can feel did a difference but you still at days end will make 5 more hp at best. It will be enough for a launch, but not enough to mash the gas to overtake someone. The 3800 is naturally anemic in the higher powerband, which is why this engine loves boost. Your engine already has boost so at most, you'll have the impression of a better working engine but real horsepower comes from internal engine mods.

[GTPer]

So the only thing holding me back on the intake is the IAT sensor. I read somewhere about using a drillbit with a grommet for the whole for the sensor? Does that sound right?

[RobertISaar]

seems proper to me.... otherwise, drill a slightly undersized hole directly into a rubber portion and slip the sensor in through that.

 

keep in mind that the PCM is expecting the sensor to be in a specific location in the intake tract and is calculating airmass temperature off of it. moving it somewhere where the sensor indicates constantly hotter or colder than what the PCM needs to know will cause temporary lean or rich conditions(until the O2 sensor trims catch up). it may or may not effect cylinder airmass calcs as well, which will effect delivered spark advance if so.

[Quaraxkad]

I have a couple of things to note... Some of you have mentioned that a CAI/FWI will not help because of the increased restriction. Even the most elaborately bent air intake tube will still flow 100 times more freely than once the air reaches the throttle body and everywhere after that into the combustion chamber. While it's true that a longer more "bendy" intake tube will be more restrictive than a shorter one, or a cone popped directly on the throttle body, either of these intakes will still flow SO much faster than what the engine is capable of due to its internal restrictions that this minor restriction makes absolutely no difference whatsoever.

 

Second, a dyno is not a reliable test of various intake systems. A CAI will draw in significantly cooler air when the car is driving down the road than it will with a fan blowing air at it on a dyno.

 

That said, anybody who thinks they felt a difference in power or responsiveness when switching from a stock box to any kind of intake: It's all in your head. If there's a difference, it's negligible, and you wouldn't be able to feel it.

[ChibiBlackSheep]

Another big thing to note when talking about intakes, is the IAT. Yes you might flow a specific amount, yes the supercharger might increase the heat itself, but your car is set to pull timing based on IAT, so if you have it just sitting in the engine bay collecting the higher intake temps, your PCM will pull timing.