So I'm planning on doing the isr mod this weekend. So I need a pipe to fit into the spot when I remove the pipe with the silencer box on it. There's a tube running from the engine into the silencer box. What size pipe do I need and where does this tube go when the new pipe is on? I'm looking for a little more growl while gaining some more torque.
isr mod question
- Thread starter jmcgahran
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The97Runner
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Hell, everyone needs that ^
PitbullRescuer
New member
OP, what hear is your 4Runner? The year will dictate what you need for the ISR mod.
If it's a 99-00, I believe the pipe is 5.625" long and 2.75" outside diameter. For the vacuum line, you have to buy a tee fitting, tee off the vacuum in the front of the manifold and run it there.
If it's a 99-00, I believe the pipe is 5.625" long and 2.75" outside diameter. For the vacuum line, you have to buy a tee fitting, tee off the vacuum in the front of the manifold and run it there.
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The97Runner
New member
What about 96-98?
98OzarksRunner
New member
Not to be an jerk or provoke an argument, but this mod, and the deck plate mod, probably actually reduce power (ever so slightly), but do make more cool noise (if you want more noise). The resonator (called a Helmholtz resonator) is designed to remove turbulance from the intake path so the air flows smoother (thus more flow). Noise reduction is a side-product; the intent is to improve airflow.
What Does an Air Intake Resonator Do? | eHow.com
The deck plate mod allows hot engine compartment air into the intake rather than bringing cool air in from the fender well (as the factory air box is designed to do), thus also reducing power. The factory engineers are not all idiots; they design these things for maximum economy and power (though in a production vehicle there are always compromises). The stock air intake system, whether the resonator or the air box, will never be a restriction on a stock engine - they will flow more air than the engine will ever need (the engineers designed them that way, even on high performance cars).
If you want your 4Runner to sound like it's going faster, do the mod. If you want it to actually be faster, leave it alone.
What Does an Air Intake Resonator Do? | eHow.com
The deck plate mod allows hot engine compartment air into the intake rather than bringing cool air in from the fender well (as the factory air box is designed to do), thus also reducing power. The factory engineers are not all idiots; they design these things for maximum economy and power (though in a production vehicle there are always compromises). The stock air intake system, whether the resonator or the air box, will never be a restriction on a stock engine - they will flow more air than the engine will ever need (the engineers designed them that way, even on high performance cars).
If you want your 4Runner to sound like it's going faster, do the mod. If you want it to actually be faster, leave it alone.
The97Runner
New member
that makes sense...
PitbullRescuer
New member
Totally different mod. Here is the 96-98 write up. (same one I need to do)
http://www.yotatech.com/f130/intake-silencer-removal-mod-installation-96-97-3-4l-engines-74837/
And here's the 99-02 write up:
http://www.yotatech.com/f130/intake-silencer-removal-mod-3rd-gen-4runner-2000-a-75168/
http://www.yotatech.com/f130/intake-silencer-removal-mod-installation-96-97-3-4l-engines-74837/
And here's the 99-02 write up:
http://www.yotatech.com/f130/intake-silencer-removal-mod-3rd-gen-4runner-2000-a-75168/
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The97Runner
New member
Thanks man ill check it out....it said page not found... lol
JWaldz
Moderator
I'm going to copy this for later usage and just quote it every time I see someone make a post about the stupid deckplate and isr mod.
Hepar
New member
Provoke an argument? Not in the least, but we should definitely start a discussion.
sportscarfan
New member
You'd only be capping off the holes in the intake tube with parts from the Home Depot plumbing aisle. One cap would need a couple fittings threaded into it for vacuum lines. Not really worth the time IMO.
SRSRunner
New member
So what your saying is that something like a k&n kit or equivalent system is also useless?
Yea your not pulling air from the fender anymore, but so what, you've increased the inlet diameter by at least 2 inches if not more. Slightly warmer air or not, I cant see how that's a bad thing. Granted it really hasn't done anything other then make noise- It hasn't hurt performance in any way either.
Yea your not pulling air from the fender anymore, but so what, you've increased the inlet diameter by at least 2 inches if not more. Slightly warmer air or not, I cant see how that's a bad thing. Granted it really hasn't done anything other then make noise- It hasn't hurt performance in any way either.
98OzarksRunner
New member
If you use the K&N drop in filter that replaces the stock filter, you probably get more airflow capacity, but not necessarily more air flow. The amount of air an engine flows is determined by the volumetric efficiency of the engine (the displacement of the engine affected by factors such as valve timing/lift, intake manifold design, etc.). Basically, an engine is an air pump but the real factor in how much air an engine CAN flow (or needs) is determined not by the air filter but by the engine internals. It is possible to restrict airflow in the intake system, but Toyota engineers designed the intake system to flow more than a naturally aspirated engine will ever need (I think they even use the same intake system with the supercharger, which probably flows 30% more air than the N/A motor). So, long story short, you could remove the air filter and feed it with a 24" diameter pipe and probably see no difference in HP (and maybe a decrease) since the amount of air NEEDED by the engine is less than the factory intake system flows now.
If you use the complete K&N intake system (57-9015-1) you might gain a little. They claim 9+ HP, but anyone who has run a dyno will tell you that you can see almost that much difference between pulls with no changes. There is a trick that cold air kit manufacturers do that can make a little power, but it's generally frowned upon by people who tune cars. They increase the size of the MAF meter portion of the intake tube which results in a leaner mixture (the MAF meter thinks it's flowing less air than it is so at WOT the mixture is leaner). It runs okay at part throttle because the ECM richens the mixture since the O2 sensors tell it that it's lean. Most engines will make a little more power at WOT by leaning them out from factory A/F (which is probably where the K&N increase comes from, if it exists at all). The K&N complete system also takes in cold air from the fender well.
Bringing in warm engine bay air with the deck plate mod probably will reduce power due to two factors. First, warmer air is less dense, therefore the air and fuel mixture has less mass, which means it will make less power (why do you think they sell 'cold air kits'?). The second reason is that the ECM will pull timing and richen the mixture as the IAT sensor detects the warmer air, to protect the engine. Both of these will reduce torque and power. Granted the intake air temp will not be what you would see with a supercharger, but in traffic or at slow speeds it will probably increase the air temp by at least 30-40 degress (more on cooler days), which means the ECM probably will pull at least 2 - 4 degrees of timing.
Removing the resonator will probably increase the amount of turbulence and standing waves (pulsations) in the intake tube and may interfere with the MAF accuracy, resulting in worse part-throttle performance (less torque, worse fuel economy while cruising). That's typically why manufacturers use Helmholtz resonators. You see this problem in engines with centrifugal superchargers if the blowoff valve returns air too close to the MAF.
These mods probably don't hurt power or economy much but they almost certainly don't gain any power or economy. The main concern in an off-road vehicle is clean air. Grit and dirt will kill an engine quickly and the factory-style paper filters do a much better job of filtering than cotton or foam filters. I'll vote for longevity over noise (or even a little more power) any day.
(Sorry for the dissertation!)
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SRSRunner
New member
lol- not like these things had any power what so ever to lose anyway lol..
But see, this is why I love this site- pointless question on my part = about the most precise answer you could get.. Right on.
Another question though lol- just out of curiosity as it was mentioned that the deckplate mod would bring in only hot air from the motor. What exactly is preventing a full intake set up like the k&n(with just the open filter) etc from doing the same? Does the air temp make that much of a difference?
But see, this is why I love this site- pointless question on my part = about the most precise answer you could get.. Right on.
Another question though lol- just out of curiosity as it was mentioned that the deckplate mod would bring in only hot air from the motor. What exactly is preventing a full intake set up like the k&n(with just the open filter) etc from doing the same? Does the air temp make that much of a difference?
I think the pipe you need to get more torque is the one that says TRD on it.
:jump:
I've got that one, its torqueariffic
Kung
New member
Actually (correct me if I'm wrong, 98), if I remember correctly from my Naval nuclear power school days, the temperature of the air will make a much larger difference than the air flow/air flow capacity, as 98 said.
The 'physics' or 'nuclear' definition of 'temperature' is 'the random average molecular kinetic energy of a substance.' Kinetic energy is, of course, energy in motion. SO....as temperature goes up, so does kinetic energy - or put another way, molecules move more. To do that there needs to be more space between molecules.
And THAT means a lower amt of oxygen molecules per 'area' (cubic inch, etc.) going into the engine and combining with the fuel to atomize it.
With an actual cold air intake, you get colder air; if temperature is lower, you have less molecular kinetic energy, which means less room between molecules, and that means more oxygen per the same cubic inch.
That means the fuel atomizes better - which is why one sees better MPGs with a CAI sometimes (IF they keep their foot out of it :biggrin2
. It's also why one sees HP and TQ gains - the engine has to work less hard to get the same amt of oxygen to burn the same amount of fuel.IMHO, unless it's a TRUE cold air intake (routing air from an area as removed from the center of the engine compartment as possible - say, a fender or wheel well), then they're not really worth spending 100's of $$'s on.
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