Engine Cost Effective Cold Air In Ca

joetrainer31

15 Year Member
Mar 31, 2013
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Okay, so this isn't rocket science or even a new discovery, but hopefully its helpful to guys like me in CA.

In CA they are super strict about vehicle modifications. According to CA law, a police officer can pull you over if he believes you may have illegal performance mods. Furthermore, he can fine you steeply and/or have your vehicle towed to the crusher (depending on the infraction).

The solution to this, while staying legal, is to only buy parts that are 50 state legal. In this context it would be a 50 state legal cai. The problem with this solution is cost. A quality, 49 state cai can be had at AM for about $79, but if you want a 50 state cai it will cost $199 (BBK), or $169 (MAC). Ouch! The law is the law and we want to abide by it. So, what's a guy w/limited funds to do?

I'm glad you asked. First, read the CA (or any other state laws governing performance mods), then find a legal way to accomplish the task at hand, for less money. That's what I did. In reading the law I saw no prohibition against retaining your factory air induction, and bringing the cold air to the filter in a more effective manner.

In order to accomplish this I bought a K&N filter because my old one was dirty anyhow, took out the factory snorkel that goes from the factory air filter housing into the fender (aka factory cai), bought a clamp and some 3inch inside diameter tubing about 3 feet long (adjustable length), attached the tubing to the snorkel via the clamp, ran the tubing down inside the fender well, and bingo, I have a cheap, legal, effective, cai.

I cannot see much difference between moving the filter to the fender well 6 inches away, or moving the fender well air to the filter in the stock location. Seems like the same thing to me. Furthermore, I do not have metal tubing in the engine bay that loves to attract heat.

I have some coupons for pep-boys so the project cost me $8 + filter. However, you can accomplish the same thing with aluminum, non corrugated dryer/furnace ducting from Home Depot for about $6 + filter. I hope this is a help to someone who is funds challenged and wants to stay legal.
 
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Just to ask but what did you see as a limiting factor in the oem system which is a cold air intake? Are you really looking for a performance gain by eliminating the airbox or is that the "effective manner"? So long as the engine isn't starved for air there can be no hp gain that I can see.
 
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Just to ask but what did you see as a limiting factor in the oem system which is a cold air intake? Are you really looking for a performance gain by eliminating the airbox or is that the "effective manner"? So long as the engine isn't starved for air there can be no hp gain that I can see.
Hey toyman! I'm not sure if I communicated clearly in my post, or if maybe I'm not understanding your question properly. Thus, I'll try to answer what I think you are asking and/or stating.

The oem system is no doubt better than the fox body system. However, I keep seeing/hearing about the gains from a cai such as BBK, MAC, SR Performance, etc. I have some doubt about their efficacy due to parts of their design (e.g., 90 degree angle and metal piping).

Next, the oem system has a short, fat snorkel that goes into the fender well, barely. I wanted to try an aftermarket cai, but due to reasons previously stated (i.e., CA smog, cost, possible design errors), I decided to make a suitable substitute that was lawful and cost effective in order to see if there was an improvement over factory. Furthermore, I failed to see the difference between moving the filter to the fender well, or devising a way to bring the fender well air to the filter. Therefore, I made the set up I described.

The outcome was better throttle response, a little more acceleration power, and a neat sound (according to my opinion). How much power? I have no idea, but I can tell it is something. Its not a night and day difference, but again, it is something. I think its a combination of a new K&N and drawing air from further away from the engine bay.

Thoughts? Comments? Questions? Cries of shock? Outrage?
 
I suspect most of the hype is marketing. Who would alter the CAI if one didn't believe there was a benefit. All I'm saying is the stock intake is a CAI and any AIT decreases by moving the intake deeper into the fender well are likely not measurable as the fender well is not a constraint. It's like saying you inhale less air in a corner of a room than in the middle. Filter resistance though may be an issue. A better flowing filter may be advantageous especially on a super charged application where more air is being drawn and pushed into the system. The test is to determine if the air intake tube is under vacuum. If it is, then there is a restriction in the tube, MAF and/or the filter. If the tube remains at 1 atmosphere there isn't an air flow gain or issue. My experience with TB response has been in either the tune or the TB signal to the ECU. This is where use over time comes into play. Certain electrical components become "lazy" over time in that they don't respond like they do when new. Also, why it's important to maintain perfect grounds for the return electrical path.
 
I suspect most of the hype is marketing. Who would alter the CAI if one didn't believe there was a benefit. All I'm saying is the stock intake is a CAI and any AIT decreases by moving the intake deeper into the fender well are likely not measurable as the fender well is not a constraint. It's like saying you inhale less air in a corner of a room than in the middle. Filter resistance though may be an issue. A better flowing filter may be advantageous especially on a super charged application where more air is being drawn and pushed into the system. The test is to determine if the air intake tube is under vacuum. If it is, then there is a restriction in the tube, MAF and/or the filter. If the tube remains at 1 atmosphere there isn't an air flow gain or issue. My experience with TB response has been in either the tune or the TB signal to the ECU. This is where use over time comes into play. Certain electrical components become "lazy" over time in that they don't respond like they do when new. Also, why it's important to maintain perfect grounds for the return electrical path.
I think we are in agreement. You simply know more about the subject than I do =). So I think we 100% agree on:

- better filter = better air flow.
- new sensors = better throttle response.
- seriously doubting the benefit of moving the filter 6 inches into the fender well can make a ton of difference. Although, I do have questions about the quality of air in the fender well (i.e., cooler air). Furthermore, I do not think the 90 degree bend in aftermarket cai is a good design. Maybe you can educate on this???

I'm not sure what you think about the following:

-there seems to be better throttle response with the ducting extending from the factory snorkel down closer to the front of the car (incoming air flow).
 
I'm not sure what you think about the following:
-there seems to be better throttle response with the ducting extending from the factory snorkel down closer to the front of the car (incoming air flow).

I think it's perception. "Seems to be" is a subjective evaluation. TB response coming on off idle has to be either TPS sensitivity or tune/tune-up related.
 
I think it's perception. "Seems to be" is a subjective evaluation. TB response coming on off idle has to be either TPS sensitivity or tune/tune-up related.
Well, I certainly appreciate the difference between subjective & objective.

Do you think there is any validity to having better performance, even if its just a bit, if the air intake charge is from a cooler source? I'm not looking for a large defense. I'm just asking. Any thoughts?
 
The most cost effective "cai" is removing the rubber silencer that is attached to the airbox and use a k&n type filter. It'll get you the same gain it just wont look as snazzy. They're more gimmicky than anything. I doubt they'd even provide 2 real world horsepower. Back when k&n first came on the market they advertised a gain up to 25 hp from just their filter. I guess America's on to em because now days their sales pitch is, buy our filter, save the planet by reducing landfill waste.
 
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Cooler air is always better. More air mass at any given volume. The point I was making was the stock air intake source (fender well) is the same so it can't be cooler.
Okay. I understand your point better now. So, the stock rubber snorkel that reaches into the fender well, if I extended it to the front of the car via tubing, that seems like it would be a better case scenario for cooler air. Agreed? If not, please educate. Thank you.
 
The most cost effective "cai" is removing the rubber silencer that is attached to the airbox and use a k&n type filter. It'll get you the same gain it just wont look as snazzy. They're more gimmicky than anything. I doubt they'd even provide 2 real world horsepower. Back when k&n first came on the market they advertised a gain up to 25 hp from just their filter. I guess America's on to em because now days their sales pitch is, buy our filter, save the planet by reducing landfill waste.
Okay, I have a k&n, I agree on the snazzy idea, but how will removing the rubber silencer help performance? It extends into he fender well where the cooler air is (in relation to the engine bay air). If I remove it that would expose the filter to engine bay hot air due to a gap between the air box and fender. Am I missing something?
 
Nah when you remove it there is a big hole in the fender and the filter is pointing right at it. When you're looking at the engine you won't be able to tell that it has been removed. It'll also give your pony a tad more growl as well.
 
Here's what mine looks like after I modified the CAI kit which includes a plate to isolate the heat from the rad and engine. Pics of the kit pieces and what it looks like installed.

94-95CAI.jpg Engine01.JPG
 
I've done it both ways k&n w silencer removed and I used American muscle's cold air. It came w that plate to block heat as well. Might be the same one that ole boy listed. I couldn't tell a difference between the two performance wise but w the cai the engine didn't look as stock.
 
Back in 2001 I had a few CAI installed on my car for testing. The shortest straightest shot made the most power. Those long BBK / MAC fender kits with all those bends made the lowest HP / TQ numbers.

After that day I've run the same type system, straight and short. Cost effective is under $20 and that's what I had into mine.

Motor12-29-05.jpg
 
Back in 2001 I had a few CAI installed on my car for testing. The shortest straightest shot made the most power. Those long BBK / MAC fender kits with all those bends made the lowest HP / TQ numbers.

After that day I've run the same type system, straight and short. Cost effective is under $20 and that's what I had into mine.

Motor12-29-05.jpg
Nice engine/bay! Please explain; how do you not loose HP/TQ with an open filter like that sucking in heated, turbulent air???
 
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