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Just got an 2001 Rav4 upgraded from the 1999 and Im new to the whole VVT-i thing. Is there any way to bypass is and put a CAI on it or is the little tube thing coming out sufficient enough?
 

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Not meant to flame your attempt at adding or improving the performance in any way, but...

I'd have to bet that the 'yoda engineers (like all the SAE-educated auto engineers at all the auto mfgs) that worked up the intake system most assuredly used every computer and lab model trick in the world to come up with the most efficient intake system for the vehicles basic intended street use.

Certainly there may be an easter egg of a couple extra horses somewhere in there, but for intended street use, you may search a long time and never find it.

If you find yourself running at/near redline patrolling the autobahn, you can try some of the mod-of-the-month trick parts that all those SAE-wannabees of the Internet HotRod Association talk about, but for normal street uses, you might be wasting your money, time, or both.

All just my 2-cents and again not meant to flame, I'm simply looking at it from a practical angle:
If Toyota/BMW/Nissan/Honda/Chebby/Ford/et al thought that "dryer vent" piping and a cone-filter would add HP/torque figures that they could tout to help sell more cars with - then you'd see it under the hood from the factory.
 
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Its not only for performance but its for the little bit of gas that will be saved to but apparently from what you guys are saying is that it wont do anything I guess?
 

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nfafan said:
All just my 2-cents and again not meant to flame, I'm simply looking at it from a practical angle:
If Toyota/BMW/Nissan/Honda/Chebby/Ford/et al thought that "dryer vent" piping and a cone-filter would add HP/torque figures that they could tout to help sell more cars with - then you'd see it under the hood from the factory.
nfafan, generally speaking I would agree with your comments above. However, I think the OEMs have multiple objectives that tend to complicate the end result. I think the power train engineers try to predominately balance and optimize a vehicle's cost, power, emissions, fuel economy. These are often opposing objectives and sometimes power is sacrificed for the other three.

For example mandrel bent exhaust systems can add HP over almost any factory system that has a cheap, quick formed OEM exhaust with many kinks, turns, sizes. But you won't find many mandrel bent exhausts from the factory due to their higher cost.
 

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RAV4Don said:
nfafan, generally speaking I would agree with your comments above. However, I think the OEMs have multiple objectives that tend to complicate the end result. I think the power train engineers try to predominately balance and optimize a vehicle's cost, power, emissions, fuel economy. These are often opposing objectives and sometimes power is sacrificed for the other three.

For example mandrel bent exhaust systems can add HP over almost any factory system that has a cheap, quick formed OEM exhaust with many kinks, turns, sizes. But you won't find many mandrel bent exhausts from the factory due to their higher cost.
No doubt about it!

Verfy few mfgs can afford the cost-no-object approach of a Porsche or Ferrari, so comprimises abound. Your ideas of well engineered headers and down-pipe being perfect examples, as opposed to the mfgs saving a buck or two in the cheaper build process.

But that said, if the mfgs really thought the extra cost of introducing features would reap them some measurably competitive advantage in the HP/MPG/performance "wars" over their competition, they'd do it. And I'm sure if they spread the cost over mass-production, it wouldn't be that huge of a cost per unit - and so it would be even more attractive to them to build the "tweaks" right into the base vehicle.

Instead, they seem to leave it to their "racing divisions" - NISMO, TRD, whatever - to offer the parts needed to acheive an owner's goal.

The mfgs build for the lowest commen denominator; the lot who merely drive their cars without further thought of anything performance beyond what the mfg spec'd out to begin with. In the eyes of the mfgs and those clients - good enough is "good enough".
 

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I don't know where this is heading.. but I can tell you one thing from working in a manufacturer of cars... if the returns on investment is greater than the investment, then they would do it. There's a law of diminishing returns and whilst it's great to have TRD bits and pieces on the cars, but the reality is, even if you did get the benefits, the sad reality is, the Mr and Mrs Jones of the world couldn't give 2 hoots about it. As long as it's good, it's reliable, it's working properly, and it's safe, then it's good enough.

Modifiers and enthusiast are a minority... until that change, manufacturers will continue to make whitegoods on wheels which Toyota has made a name doing.

From RAV4Don's point, with the additional balance is that when you increase stress to the engine to extract more power, the weakest link in the chain will be the first to break down. Aftermarket modifiers say they can extra x% with bolting on this item but what they don't have to manufacture to is emissions, noise, local regulations, reliability and most of all, warranty for the WHOLE vehicle.
 

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Thats why its up to us enthusiasts to modify and make our RAVs unique! But this topic has gone way off track now.
 

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GETING BACK TO THE ORIGINAL QUESTION:
Yes. If you really want to put on a CAI you can. There are many ways of doing this as many here will tell you. I am working on an easier and more effective all year round solution for my 2001. I can take pictures and up-date you on my progress if you like. One thing I can tell you is we need to modify the mount for the overflow tank for the coolant to get it out of the way. After that there is two ways you can go with my method. I'll keep you up to speed on it later.

With this type of modification some may see a little improvement in HP and fuel millage around town but the most noticable millage gain will be on the highway. For long trips you may add 10-20 more miles on a tank of fuel. This can be big if you travel alot like I do. I'll be the test. This is something I'm going to try and I won't be investing alot of money since I will make all the parts I need.

Smell you later!. M. :lol:
 

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PhalC1 said:
Just got an 2001 RAV4 upgraded from the 1999 and Im new to the whole VVT-i thing. Is there any way to bypass is and put a CAI on it or is the little tube thing coming out sufficient enough?
Not detracting from anything said already, but one of the big reasons for the airboxes is "emissions standards" since, as someone else said, they have to toss emissions into the mix to get it to pass inspection in certain states and/or countries.

If you're not concerned about emissions, by all means, rip that crap out of there, but... From everything I've heard here in other threads, the ECM programming of the RAV4 really keeps a CAI from adding much if anything, if you don't go the whole route of adding a custom exhaust as well, then "reboot" your ECM... Air in, air out... That sort of thing, and it gets all math-related..

As for me, until my 2005 RAV4 leaves warranty, I'm pretty much going to leave the internals stock. After that, I'm going to go nuts... Hopefully by then, someone will have figured out how to add the tC Supercharger and an as-yet-created 6-speed manual transmission.

Wayne
 

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Wayne said:
PhalC1 said:
Just got an 2001 RAV4 upgraded from the 1999 and Im new to the whole VVT-i thing. Is there any way to bypass is and put a CAI on it or is the little tube thing coming out sufficient enough?
Not detracting from anything said already, but one of the big reasons for the airboxes is "emissions standards" since, as someone else said, they have to toss emissions into the mix to get it to pass inspection in certain states and/or countries.

If you're not concerned about emissions, by all means, rip that crap out of there, but... From everything I've heard here in other threads, the ECM programming of the RAV4 really keeps a CAI from adding much if anything, if you don't go the whole route of adding a custom exhaust as well, then "reboot" your ECM... Air in, air out... That sort of thing, and it gets all math-related..

As for me, until my 2005 RAV4 leaves warranty, I'm pretty much going to leave the internals stock. After that, I'm going to go nuts... Hopefully by then, someone will have figured out how to add the tC Supercharger and an as-yet-created 6-speed manual transmission.

Wayne
Wayne, I don't see the intake having much if anything to do with emissions. Most intakes today are designed to reduce the roar of air intake on WOT and some plumbing that many connect to the intake that could easily be rerouted. Other than that there is nothing emissions related that should be adversely affected with a well designed aftermarket intake system.

OEM intake systems are a compromise and can definitely be improved upon without any laws being broken. More air, and particularly denser cold air, will most definitely enhance engine performance. The ECM , PCM or what you want to call it will adjust, to a limited extent, on the increased air by enriching the fuel mixture. Recall that engines are basically air pumps and the more air the better under WOT conditions.

I agree that improving the intake without improving the exhaust won't get the big gains possible by doing both. Also, changing the intake should not affect one's warranty.
 
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