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Discussion Starter · #1 ·
Most cars don't have a gapping hole in the header like our cars do. This is the reason for the prominence of the FWI in other cars. You get air from the fenderwell eliminating alot of the convoluted bends that a stock airbox assembly normally has.

Air from behind the headlight is just as cold as air in the fenderwell. The point is to source air from outside the engine compartment.

For the 3800 vehicles you have 3 options.

1. Gutted stock airbox for 99+ models. This is a cheap solution. It sources air from the same point as a CAI or FWI setup. A CAI or FWI will not give you colder air than a gutted airbox.
pic of gutted airbox
Pic of gutted airbox FWI

2. CAI a little pricy but you don't have to fabricate anything. Draws air from the same place as a gutted airbox.
ZZP Wizaired
Intense SLP intake

3. FWI more fabrication that either option above, but you have straighter airflow compared to the Gutted FWI setup. Even prefab kits require more work than options 1 and 2. Also, more trouble to change the airfilter.
Speedbuilt at PFYC
Club GP custom FWI
 

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I have something to debate. It is my beliefe based on a test that a FWI will give me cooler air than a gutted airbox or CAI. This can be tested by reading the resistance of my IAT sensor. I have tested all three setups on a 1998 Oldsmobile Eighty Eight and found the FWI to be the best for delivering colder air and I agree that it provides straighter air. The reason for this, I believe, is that it moved all my intake tubing away from the tube that directs 180 degree coolant to my radiator. The FWI I have is custom from thicker PVC which wil be less absorbant to heat than an aluminum tube or metal tube in general would.
 

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Discussion Starter · #6 ·
I have something to debate. It is my beliefe based on a test that a FWI will give me cooler air than a gutted airbox or CAI. This can be tested by reading the resistance of my IAT sensor. I have tested all three setups on a 1998 Oldsmobile Eighty Eight and found the FWI to be the best for delivering colder air and I agree that it provides straighter air. The reason for this, I believe, is that it moved all my intake tubing away from the tube that directs 180 degree coolant to my radiator. The FWI I have is custom from thicker PVC which wil be less absorbant to heat than an aluminum tube or metal tube in general would.

Good point. I have never heard that one mentioned before.

Do you have any pictures of your setup?
 

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My FWI

Here's some pics of my FWI that I put together...

I'm very satisfied with the performance of my intake and the cost!

A coupler from the hardware store
Some extra wire to extend the IAT sensor into the fender well
3' of tubing
9" K&N cone air filter

http://people.msoe.edu/~oblamskn/GTP/Pictures/Mods1/newintake/intake6.jpg

http://people.msoe.edu/~oblamskn/GTP/Pictures/Mods1/newintake/intake7.jpg

http://people.msoe.edu/~oblamskn/GTP/Pictures/Mods1/mod1engine/mod1engine4.jpg

Just need to get some reflective insulation to help with heat...

Nick
 

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I do have pics and hope to have them up soon, they are on my server which is temporarily down. If was easier for me to do it on my eighty eight because I moved the vapor canister leaving a nice big hole in the fender so no cutting involved.
 

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the FWI is probably the best intake...but thats all it is an intake. it just makes noise really.

look at so called 'super cars' they have very similiar airboxes generally. just bigger.
 

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You are right, super cars from the factory do have an airbox and the reason why is that no one want to get a brand new car and have it sound like darth vader on startup. Most super cars used for racing end up with better intakes. An intake does make a big difference in horsepower, ~10 hp from $40-$60 homemade is a pretty sweet deal no matter how synical you are about tiny gains because they all add up.
 

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No its not going to be to the wheels, no one said that. But hp is hp and I can't get over how rediculoud people sound when discounting small, inexpensive gains. If you want to rate hp gain mods then no, CAI and FWI will not be at the top of the list. But it is certainly a good way to start and I'd love to hear that be disputed. Either way you gotta pay to play, some just play with more money and others with patience. Besides, if my FWI can deliver straighter air than someone's gutted air box then I will have less problems with flow in the intake and possibly even less erratic data to the PCM.
 

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all i was saying is it's just an air intake. and it's mostly just sound.
just like a cat-back exhaust.
 

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magilson said:
No its not going to be to the wheels, no one said that. But hp is hp and I can't get over how rediculoud people sound when discounting small, inexpensive gains. If you want to rate hp gain mods then no, CAI and FWI will not be at the top of the list. But it is certainly a good way to start and I'd love to hear that be disputed. Either way you gotta pay to play, some just play with more money and others with patience. Besides, if my FWI can deliver straighter air than someone's gutted air box then I will have less problems with flow in the intake and possibly even less erratic data to the PCM.

How is your FWI delivering straighter air than a cai or even an open cone?


I have never been a fan of the FWI's. Yes I do belive that they provide cooler air, however the trade off of having to suck it 3 feet throught a tube after the filter seems like more of a loss than the cooler air could gain.

I have email'd several companies asking them all the same question:

"If one was to measure airflow through a straight tube, say with a vaccum on one end, would the cfm be the same as a tube of the same diameter, bent at 45 degrees or 90 degrees, or any combination of the 2?"

I am definately curious as to their answer.

Jason
 

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for what it's worth an engine only sucks in as much air as it needs give or take.
oh ya and ram air doesn't work.
 

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Ram air doesn't work, wait untill I let formula 1 know, man will they be mad...
 
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If you had Ram Air going into a totally sealed airbox, you would have to be going highway speeds (70+) to get any benefit. IMO its not worth it, as dryer ducting sticking out of the bottom of the car looks like crap.
 

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Discussion Starter · #19 ·
I don't believe what I'm reading.

for what it's worth an engine only sucks in as much air as it needs give or take.
all i was saying is it's just an air intake. and it's mostly just sound.
You've come to the right site because we are here to educate. Both of your statements are dead wrong.

An Engine sucks in as much air as it can get, not as much as it needs (it needs more than it can get). The intake manifold and intake valves are enough of a restriction to airflow that you can't get volumetric efficiency up to 100% on a Normally Aspirated engine. When you add a restrictive airbox from the factory you lower the volumetric efficiency even more.

Now that we've got that part straight. An engine, like your Maxima, makes more power without an airbox than with one. The 3 types of air intakes discussed eliminate the restrictions to airflow that the stock airbox has. They also sound good. The same restrictions apply to a catback system. A car without a catback has a lower amount exhaust restriction than a car with a full exhaust. Swapping a stock catback to an aftermarket one that breaths better lets the engine operate more efficiently and makes more power. It also sounds better.

As for Ram Air, stick your arm outside the window when your driving down the highway. Do you feel that airflow that is pushing your arm back towards the rear of the car? Now imagine that same force pushing air through the holes in the hood of a GTP.
 

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ZR2_S10 said:
I have email'd several companies asking them all the same question:

"If one was to measure airflow through a straight tube, say with a vaccum on one end, would the cfm be the same as a tube of the same diameter, bent at 45 degrees or 90 degrees, or any combination of the 2?"

Jason
This is what I posted in a different topic...

Yenick1 said:
I have the FWI and I was thinking about making it out of PVC or some other pipe like that because of the smooth wall and such but instead went with some custom tubing from Intense Racing for a few reasons. First, it's important to try to stay away from 90 degree bends and such. If I remember right, a 90 degree bend equals about the same amount of resistance as a 130" or so of straight tubing. Also, I thought it would probably be more important to go with the 3.5" tubing than the 4" tubing and have the air go straight into the TB instead of going with the 4" - 3.5" reducer coupler. This adds resistance to the system and also creates disturbance in the air flow creating voids and possibly turning a pretty laminar flow into a turbulant flow.
I double checked and flow through a 90° elbow is roughly equivalent to having the same resistance as a straight section of pipe 40 times that of the diameter. (160" of pipe for 4" tubing) This is a reason I feel Ram Air doesn't work well on the GTP, because of all the twists and turns the air has to go through from the entrance to the engine. It would me more functional if the air went straight in and bend down directly into the engine.

Didn't calculate CFM or anything though...

Also, as far as...
NismoMaxima said:
all i was saying is it's just an air intake. and it's mostly just sound.
Well, you have to think of an engine as an air compressor basically, the more/faster you can get your air in/out of the engine, the better.

The addition of an intake will not add drastic amounts of HP but will support those mods that do add the most HP and help them work more efficiently.

Nick
 
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