I was looking at the intake setup on the Rav4 v6 yesterday. I was also looking at the K&N apollo intake I bought for a project that did not work out.
A quick review of the piping on the Rav4 intake shows that the air actually comes through only one source. The pipe connects to the bottom of the box the airfilter sits in. It then runs down and splits into both a resonator box and a pipe that curves back up into the fender and sucks air from the engine bay/fender (so stock you are only getting hot air for the most part).
What is interesing and makes my decision to play with the setup is that the resonator box and the split feed pipe for the air are both connected to the box via a shorter straight pipe section. This allows for ease of installation/removal in three pieces. What is even better is that the short straight pipe ends right at the bottom of the engine bay where it connects to the resonator that sits in the fenderwell.
It took no time at all to remove the resonator and air intake pipe from the fenderwell. total of 4 10mm bolts hold everything in. You have to partially take apart the fender lining, another 4 bolts, a few clips and a nut. Need to remove the driver side wheel to make space.
At this point you have just a straight pipe from the airbox to the fenderwell left. It is popped into the air box (I will get to that later) and is otherwise sucking air directly from a colder source than the curved feed pipe was.
Now it is a simple matter to use a coupling to attach the K&N airfilter to that pipe. This is now a cold air intake setup.
The stock airbox has a restrictive filter in it. However, since you now have a highflow filter before the air enters the box, there is no need for that filter anymore. By removing the filter you are essentially leaving a expansion charge box for the air coming in. The thing is you will need to line the edge of the box with a gasket or foam padding to seal it from the outside air to avoid leaking hot air and dust in (My solution I have in mind is to cut the old filter up and leave its outer edge as the seal). You will also need to brace the intake and pipe because it is plugged into the box loosely. Again a rubber gasket of sorts and in my case duct tape and zipties did the job fine as a temporary solution. I can see a simple home depot brace can be made to use the stock mounting holes for the resonator and feed pipe.
The end result is essentially what the Cold air intakes like the Typhoon is trying to accomplish while keeping all stock plastic pipe and intake track up to the throttle body. I prefer this because the whole system is abs plastic and not as subject to heat soak and you are not affecting the MAF area.
The test was today when my wife took it out. No cel, no issue with funny running but of course no proof it did improve any performance either. I will get to romp on it tomorrow since I have to take it to the shop for brake pads.
What would be really nice is to have a before and after dyno with intake temperatures logged. I can easily simulate the different setups by simply reinstalling the stock filter, remove the Apollo, do a run and then reverse and do a run. Hard part will be getting the car from my wife for the day.
I know this thread is worthless without pics. I will work on getting some this coming few days.
A quick review of the piping on the Rav4 intake shows that the air actually comes through only one source. The pipe connects to the bottom of the box the airfilter sits in. It then runs down and splits into both a resonator box and a pipe that curves back up into the fender and sucks air from the engine bay/fender (so stock you are only getting hot air for the most part).
What is interesing and makes my decision to play with the setup is that the resonator box and the split feed pipe for the air are both connected to the box via a shorter straight pipe section. This allows for ease of installation/removal in three pieces. What is even better is that the short straight pipe ends right at the bottom of the engine bay where it connects to the resonator that sits in the fenderwell.
It took no time at all to remove the resonator and air intake pipe from the fenderwell. total of 4 10mm bolts hold everything in. You have to partially take apart the fender lining, another 4 bolts, a few clips and a nut. Need to remove the driver side wheel to make space.
At this point you have just a straight pipe from the airbox to the fenderwell left. It is popped into the air box (I will get to that later) and is otherwise sucking air directly from a colder source than the curved feed pipe was.
Now it is a simple matter to use a coupling to attach the K&N airfilter to that pipe. This is now a cold air intake setup.
The stock airbox has a restrictive filter in it. However, since you now have a highflow filter before the air enters the box, there is no need for that filter anymore. By removing the filter you are essentially leaving a expansion charge box for the air coming in. The thing is you will need to line the edge of the box with a gasket or foam padding to seal it from the outside air to avoid leaking hot air and dust in (My solution I have in mind is to cut the old filter up and leave its outer edge as the seal). You will also need to brace the intake and pipe because it is plugged into the box loosely. Again a rubber gasket of sorts and in my case duct tape and zipties did the job fine as a temporary solution. I can see a simple home depot brace can be made to use the stock mounting holes for the resonator and feed pipe.
The end result is essentially what the Cold air intakes like the Typhoon is trying to accomplish while keeping all stock plastic pipe and intake track up to the throttle body. I prefer this because the whole system is abs plastic and not as subject to heat soak and you are not affecting the MAF area.
The test was today when my wife took it out. No cel, no issue with funny running but of course no proof it did improve any performance either. I will get to romp on it tomorrow since I have to take it to the shop for brake pads.
What would be really nice is to have a before and after dyno with intake temperatures logged. I can easily simulate the different setups by simply reinstalling the stock filter, remove the Apollo, do a run and then reverse and do a run. Hard part will be getting the car from my wife for the day.
I know this thread is worthless without pics. I will work on getting some this coming few days.
