I had a couple friends today convince me to insall a simple cone filter on my car. Now my Max makes a nice throaty "muscle car" sound while accelerating, but it seems like it makes either no difference in power in the lower range, or it might even lag slightly down in the lower ranges. Up at the higher end, however, it seems to pull a little (mind you, a LITTLE bit) harder.

Is it in my head? Is it actually lagging more at the lower RPM's, or is it probably about the same with just a cone filter?

I probably just need to break down and buy an injen CAI...

 

i think they all behave this way.

 

Mine is the same way, I just have the filter. It's worth it though, for that sweet sound.

 

Change the stock y-pipe. If you can, change the b-pipe too, this will resolve your low end loss and even give you more low end to launch harder.

 

get rid of the black box and get a mid pipe. i think RVM still sells them for about $50.

then get a y-pipe.

 

That is completely normal.

 

Unless done properly you *will* loose power as the engine will be drawing hot air from the compartment rather than from the outside. There were seveal sites that proved with dyno runs that an intake doesn't really matter unless you go with high end engine mods. The thing is, IMO you find it to pull as it lags in low end, so once you rev up you gain some of the lost power and woah it pulls. Not really. Ok and don't flame do the research people. Sound yes, performance.. not really.

 

bought mine mainly for the sound. wasnt really expecting much for "high end gains" anyway, seeing that all they provide is a few hp

 

for sound, CAI > popcharger

 

Midpipe solves this somewhat... As freddy said above RVM makes one as well as frankencar, and PR.

 

damnit MR.CLEE that girl is so hot who is she and where can i get one??

 

O.K. guys here is your lesson for the day:

1st of all, to co_maxima98: Where is your Intake air temperature sensor(the little resistor looking thing originally placed in your factory airbox)? If it is just hanging out in your engine bay then you will definetely be losing even more power than just the loss from the cone.

2nd of all, your ecu recieves a signal from the intake air temperature sensor
telling it the temperature of the air that is coming into your car. It then makes a decision based on the temp signal it recieves, that decision is how lean or rich to make the air/fuel ratio. The more hot the air is the more lean it makes your air/fuel ratio, and vice versa the colder the air the more fuel is sent to your motor. hence, the colder the air, the more power plus i'm assuming you know that cold air is more dense than hot air. that is why you are losing power.

I suggest you go to radio shack and buy a 47k ohm resistor and rig it up by placing it in-line inbetween your IAT sensor(intake air temp)harness(where the sensor plugs into the wire lead going to your car)or just cut off your iat sensor and split and strip the wires and hook up the resistor directly to the wire NOT THE IAT SENSOR just hanging there. make sure you seal up the connection with electrical tape. before you go doing this make sure your car is turned off. once you put in the resistor start up your car and go for a drive. YOU WILL BE AMAZED at the difference in all around throttle response and "power".

I strongly suggest you buy a stillen or jwt pop charger!!!!!!!!
they are superior if you asked me and iv'e been fixing up nissans for 8 years now. you can(or anyone else who tries this) e-mail me with ANY questions at cullenj76@yahoo.com

 

My turn for the school lesson and I'm pretty certain it will explain the lowend power loss. The stock intake track has two resonators placed in it's intake tract (aka black boxes). These resonators store air and they also slightly pressurize the intake tract giving the VQ a linear delivery of air, to a point. Example, when you're driving along at 40mph in 4th gear and punch it, you get a surge of power due to the resonators. When you add an open element filter, you negate the pressurization effects of the stock intake therefore when you punch it in 4th at 40mph you don't get near the intial surge of power as you did with the stock intake. There really is no true lack of power at WOT at any rpm above 2000rpms with the open element filters (I've proven this on the dyno), but there is a slight lag when you first punch the gas when you're below ~3500rpms. The lowend "loss" has nothing to do whether or not you have a hybrid intake, POP style, or a CAI. ALL open element filters will have this lag and/or loss. It's just a trade off.

Also, on the dyno, the stock intake flow JUST AS GOOD as the hybrid intakes up 5400rpms. After that, the hybrid is able to hold on to power a little better (3-5 hp) ---no peak gains though. This is where the POP/CAI/hybrid has the advantage and this is where you'll see some performance gains in the 1/4 mile. I've proven this on the dyno with my Maxima.

Open element filters, whether they're CAIs or hybrids, are also prone to sucking in hot air which isn't a good thing, but the truth is once your engine has heat soaked (hot weather), it doesn't matter what you have attached to the other end of your throttle body because you're going to be slower. PERIOD.


Dave

 

School's in? Hey, I am always looking to learn. "Only you can prevent forest..." Opps, wrong subject.

About all this hot air injestion... Those of us with HAIs (aka - K&N cone filter, jwt popcharger, Frankencar) are just making loud noises on the highway and not producing any performance gains? And all this is because we are breathing hot air from under the hood into the intake. What changes then if one were to say pipe outside air into the area where the cone filter sits? Would one note some performance gain if the intake were shielded from the hot engine and exhaust manifolds. I have done both - pictures I have but web hosting I do not; anyone want to host some pics? I formed a heat shield box using (HVAC) aluminized fiberboard and tape. The shielding keeps the Frankencar mid-pipe and K&N Filter cooler. I also plumbed two 1.5" clear vinyl tubes from the front valance to blow outside air directly at the filter and intake area. The intake air temp sensor also resides in the cooled down shielded area. I don't have dyno slips but my butt dyno appreciates both the sound and the acceleration.

Now what's all this about a placing a resister in line with the IAC??? Interesting, are you saying the resistor fools the ECU into thinking the engine is breathing in cooler air? Just slice one of the the IAC wires and splice in the resistor? Hum, maybe that's next on the mod list, even before the Y-pipe... Be Safe, Mark V. (Still wondering why I can't update my signature with mods - I no longer have the unhacked OSCAI/HAI...)

"I suggest you go to radio shack and buy a 47k ohm resistor and rig it up by placing it in-line inbetween your IAT sensor(intake air temp)harness(where the sensor plugs into the wire lead going to your car)or just cut off your iat sensor and split and strip the wires and hook up the resistor directly to the wire NOT THE IAT SENSOR just hanging there. make sure you seal up the connection with electrical tape. before you go doing this make sure your car is turned off. once you put in the resistor start up your car and go for a drive. YOU WILL BE AMAZED at the difference in all around throttle response and "power"."

 

Why are you quoting me? I know what an Air Temp Sensor does, so thats why I did this..




Dave,

 

The issue of hot air injesting into the engine is the very reason why I try to avoid getting open air intake kits. This has been proven true when I had my 2nd Maxima 4 years ago (I'm on my 3rd one now). I used to have a K&N conical filter with a MAF adapter. During hot summer days (in California), my car would be slow and sluggish. Hesitates during acceleration. But during cold winter and spring months, the car performs completely opposite. That proves that cooler, more dense air, benefits engine performance. I had the same experience with my Toyota Tundra. I didn't use an open air system but I hacked the stock air box. I cut a pretty large rectangular opening on the front side of the air box and fastened a wire mesh behind it (using liquid nails) to keep big particles and debri from entering the airbox. The engine was happy up until summer time. The performance went down hill, the hotter it got, the more bogged down the engine got. Now this is just a hacked airbox but the principle is the same as an open air filter. Hot air is now entering the engine versus when the air box was completely sealed. So to resolve the issue, I came up with a way to channel cooler air from behind the front grille of the vehicle. Now I'm planning on doing the same to my Maxima. I figure that the best way to achieve cold air intake is to preserve the stock airbox in the Maxima and find a way to channel more cooler air into the airbox.

 

My Max: 97 SE 5 Speed
Mods: JWT Popcharger, Frankencar Midpipe, Y & B Pipe, Test Pipe, Magnaflow Muffler

I know the least of anyone here but this is what happend to me. I have been working on my Maxima trying to get the right thing here and there. Today my Frankencar Midpipe arrived. I had it installed in the afternoon. I live in Mississippi. The temperature was in the mid 90's I believe and my car engine was really hot from alot of driving.

After the install, I took off and did a few redlight/greenlight runs. And then got on the interstate. At first I wondered if I had done the wrong thing by adding the midpipe. If anything the car seemed a fraction or two slower then just the JWT setup. Here is one of the test runs in the heat.

http://www.myweb.cableone.net/kindre...kenoutside.wmv

For at least and hour, I wondered if I had made the right deceison. Or was there a better decesion. And if you see the video clip "I know that Magnaflow Muffler has got to hit the road !!" Going to try the dynomax super turbo.

Anyways I go home and let the car cool down several hours until it gets dark. The engine was cool and it was also cool outside. I went out for another test run and the car impressed me. This time in the cool of the night,the Max was just flying down the road. Its hard to say but i think the car is faster with the midpipe but its in the higher rpms of each gear.

Heat played a huge role in my car today, and im up for any ideas on how to get air to the intake. Is the Place Racing CAI a better intake for me? I dont know, would love some thoughts.

I also took out the old stock plastic intake that goes over the radiator hose. I didnt see how it was getting any air/wind from its front location.
The boost sensor that was connected to it is now just cliped to some wiring up in the same location. I have no idea if this will upset anything.

 

If you can find a way to fabricate an airbox similar to this chances are you'll be able to draw cooler air and keep your current intake setup. You'll probably ask where and how can you get cooler air into the air filter. We'll if you are comfortable with cutting an opening thru the front driver-side wheel well hump, perhaps the same diameter as the opening that's in the airbox then you can use some kind of a hose or plastic pipe to channel the cooler air into the airbox. Just an idea.

If anyone knows of a place or someone that can fabricate something like that, I'm sure there would be enough interest and perhaps a group order can be made.

 

Yes, that is exactly what the resistor does. Believe me it does sound fishy. I've been modding nissans for 8 years now(91 300zxTT,91 se-r,95 se-r,93 se-r,91 maxima, now a 91 se-r and a 95 maxima) and it frankly upset me and my ego to think that i never thought of the idea myself. I'll explain fully here in a couple of hours after i go out to eat with my girlfriend to buy me some " Oh, it's ok if you get on the web hone" time. By the way it is completely safe and offers CONSISTENT results. Made more power than my intake and exhaust on a dyno. doubters may scoff, but don't knock it till ya try it.

 

According to the Nissan FSM, the IAT (air temp sensor) does NOTHING in terms of adjusting air/fuel/timing (aka something that would actually make any true performance gains). Maybe Sentra's IAT is different than the Maxima's IAT.


Dave

 

like i said don't knock it till ya try it. actually I've tested this(or else i would not be sharing this info) on my maxima not the sentra(does not make much difference with a t3/t4 setup on a gti-r motor!). This DOES affect the a/f ratio as monitored by air/fuel meters on and off the dyno iv'e seen it with my own eyes(and felt it). Like i said doubters may scoff, because i was a doubter. This is how it works: (not for you dave since you have a fsm in front of you?) the iat actually recieves and sends the temp in the form of minute volts of electricity(milliamps,volts,ohms), not actual temperatures. For each change in temperature the ecu recieves a voltage change from the iat. Then the ecu reads this signal and adjusts as needed. Now, the resistor is 47k ohm and it resists signals of hot temperatures to the ecu. This fools the ecu into thinking that there is consistent cold air entering the engine. THAT is how it works.

 

Hey Dave B, you and I must have defective FSM's cause mine says the same thing as yours. According to the FSM ('97), the intake air temp sensor is for diagnostic purposes only. Must be a misprint. I'll bring this oversight up to the people who made the car at their next board meeting.

Dave

 

so. your fooling the engine into thinking its getting freezing cold air. then, thinking its getting such rich cold air, cold air being more dense the engine needs less of it, thus air less into the combustion chamber? or simply does the ecu add more fuel to the A/f ratio? so your really just increaseing the amount of fuel it pumps into the engine right, running rich? while this might make you faster.... doesn't it just waste gas and cause the engine to work as it was unintended to? maybe its just me but this seems like a bad idea. i'm sure there is good reasoning behind why an engine has less pickup when it gets hot air. simply flooding more fuel in there doesn't seem like a smart idea. but i don't know a heck of alot about it but it seems stupid to want to make an engine think its getting better air then it really is. comments? suggestions?

ps. this sounds like the drop resistor mod. cheap, fun, makes you faster, but too costly in the longrun.

 

Thats the penalty for your noise and high end power. Take it out on the highway. You wont feel lag there.

 

Got the same misprint in mine too.

 

MaxiMarks 95 SE
** Heatshield Box - HVAC fiberboard and tape **

Mark says:

The shield keeps the heat off the filter and aluminum midpipe. Not seen in the pics are two 1.5" vinyl tubes that channel air from the front valance to below the filter.

Photos Below:

 

I guess you're right, I am knocking this resistor mod

I think you need to understand some things about the way cars run in weather conditions. When it's hot out, the air is less dense therefore there's a lower availability of oxygen. When it's cooler out, the exact opposite is true. Running this resistor mod will do absolutely nothing for you...even if the IAT worked on the principle that you believe it does (it doesn't). The resistor would fool the ECU into believing it's 30-40 degrees cooler outside than it really is. The ECU would then richen the fuel mixture because it believes the air is more dense. The truth is the air is less dense in the hot weather therefore you'll end up running rich which is exactly NOT what you want to have happen. The goal of the A/F ratios is to be running on the verge of too lean. This makes the most power. By running rich you kill your peformance and fuel mileage.


Dave

 

I AGREE THIS IS A MOD ONLY FOR PEOPLE IN HYNDAI ACCENTS.