I have a '99 Grand Caravan with the 3.3L V-6. I really like the van especially since I got the head gasket problem fixed. Van runs great now. Get 22 - 24 mpg on the highway. Looking for better gas mileage as well as better performance without going wild on the mods (like I'm doing on my Mazda). I already switched to a K&N filter (straight replacement so as to keep the black box), but am now interested in changing this set-up. Anybody ever gone to a high-flow cone filter and replace the stock plastic tubing? If so, how did it work? Any suggestions? I'm thinking of adding piping to drop the intake lower down and further away from any engine heat.

What about a larger diameter exhaust to reduce restriction? I'm ready to go with a larger diameter system from the catalytic converter on back with a Magnaflow baffle. Anybody ever do this? Results? Talk to me.

 

Hi. I have a '93 Grand Voyager SE with a 3.3L V6 and I've made a custom CAI for it. It's very simple, easy and cheap.





I just used 2" ABS tubing (one large piece cut in two, and one 90 degree bend) and 4 2" flex rubber mouldings.

The tube was $11, the 4 flex rubber mouldings $28 ($7 each) and a Tuned cone filter $34. Everything else is pretty much self explanatory, although you have a 99 so I can't guarantee anything. I know that you'd need to remove the air silencer (resonator box) and the airbox and you could effectively have the same setup as mine and have it go to where the original airbox is, you'd probably have to do some expirementing.

For more ideas, you can check this out:

http://www.allpar.com/model/m/air-intake.html

As for bigger piping and muffler, it's been done! Tried tested and true, bigger piping and an easier flowing muffler can only benefit you. Combined with a CAI, you should see some nice power gains.

 

Well, I did the K&N, but wasn't super impressed. It was the flat filter which was the straight replacement for the stock, so that I didn't have to do any modding of pipes. I decided to go to a cone filter set-up and bigger piping. I'll let you know what I think.

 

Okay. For anybody who might be interested, I finally bit the bullet and modified my intake. Cool.... I am so happy with the initial results. I finally came up with a set-up that I was pleased with in terms of shortening the amount of tubing, using large tubing and using a high-flow, double cone filter (with an inverted cone filter at the top). Upon start-up after everything was bolted up, I noticed a significant improvement in the "perceived" amount of air flow (less restrictive) based on the way the van started, the change in the noise of air flow and throttle response (in neutral, in my driveway).

No offense K&N. This new set-up replaces the flat-style, stock-replacement K&N filter that I already have in the van. Many of my friends said I should leave it at that, but I just have a hunch that I may be able to out-due that. And my new set-up is les than 1/2 of the cost of the K&N filter.

After putting away my tools, I drove down to the gas station to top off the tank because I'm going on a rather lengthy roadtrip soon over several mountain passes (I live in the great state of Washington) and boy..... I thought my van drove nice before! Now, I have even better (touchier) throttle response and on a section of road where I feel I normally would have had to give it some gas to maintain my speed, I was actually slowly accelerating and I wasn't even touching the gas pedal.

So, now for the road testing. Sunday morning I go to the airport to pick up a relative flying into town. That's about a seventy mile road trip. Then, starting Monday, I begin a road trip that should cover at least 500 miles. This is going to be my test run with the new set-up. I am keeping my fingers crossed that my gas mileage will be better. How much? We'll all have to wait and see. I'll make another posting when I'm done and have had a chance to make some calculations. If all goes well, I may try to post some pics and show the rest of you what I did in case you are interested.

Next mod will be a 2-1/2" cat-back exhaust! My goal? 25mpg consistantly on higway trips (occasionally 27+ on highway trips NOT over mountain passes). Anybody else getting that with a Grand Caravan?

 

a stock cold air intake from a neon works just need to cut a bit ill post up picks of mine
soon as i take picks

 

Cool. Well, my first little experiment is over. I drove to the airport to pick up my aunt and here are my observations...

The van ran great (no noticeable major side effects).
The van was noisier during cold start/warm-up and when sitting/idling.
There was no real noticeable difference in noise when driving.
Gas mileage "seems" better, but this is preliminary. More on that later.
I set the heads-up computer display on the overhead console to show realtime mpg estimates. When going up hills on the higway the mpg reading seemed to drop lower/faster than normal. Conversely, I noticed that on flats or near-flat conditions and on downhills the mpg reading went higher than before and faster than before. I attribute this to faster throttle response because of less restriction. Although it went lower on the uphills, I felt that I was maintaining speed or accelerating when before the mod it wasn't. My guess is that it should be expected to see a wider and faster range of mpg reading, but my prediction is also that the overall mpg will be higher than normal. I realize that the ECU will compensate for the greater air flow by pumping more fuel. However, that's not entirely accurate. The ECU will do what it is programmed to do and that is to attempt to maintain the ideal air/fuel mixture under the driving coniditions. It's just that now, with the less restrictive set-up, it will do so faster and a little more to the extreme because the engine is able to run more efficiently. We'll see if I'm right.

Okay, I admit that I couldn't resist stomping on the gas pedal once late last night during my initial test drive after completing the mod. WOW. I always thought that the van was pretty good on acceleration (for a van with a mid-size V-6), but it seemed to rev faster and more easily up to and into the higher RPMs. Again, my guess is that this is the results of better/easier air flow.

I'm now dreaming of a large exhaust to complete this (no, I won't do anything more radical like I have to my little "tuner" Mazda, but who knows....) Maybe I'll be the first to start a mini-van Daytona category!

 

Okay.... hope this works. I'm going to add some links to three pics that I took of my mod. Hopefully, anybody who wants to will be able to easily see what I did. Plus, I'll try to give a little explanation so as to help out.

<img src="http://img465.imageshack.us/img465/1606/219060093du.jpg" alt="Image Hosted by ImageShack.us" />

This first pic is a side/angle view of the completed mod. From left to right... the blue piece is a silicone adaptor going from 2.5" ID to 3" ID. The next piece which cannot be seen is a short section of 3" ID aluminum tubing that I cut to just under 2" in length. It is the link between the blue adaptor and the next angled adaptor which is the stock 3" rubber hose with clamps originally used to connect that bottom of the silencer box to the lower air filter box. The next piece is more of the straight 3" ID aluminum to which the red cone fileter is attached. The larger chrome half-cylinder shield is a heat deflector I got off of ebay (can't remember the price, but it wasn't that much). This helps reduce heat transfer from the engine. Because of the short design I know that I am getting a little bit warmer air from the engine compartment, but the trade off is the much greater sir flow directly into the throttle body. Plus, what is not seen is that I left the stock air filter box which still funnels air directly at the bottom of my new set-up, so it's not like this new set-up only gets warm air. By leaving the stock air box I also don't have to find a place in my garage to store it!

<img src="http://img106.imageshack.us/img106/8246/219060083pd.jpg" alt="Image Hosted by ImageShack.us" />

This second pic is a general frontal view. The forward-aiming placement of the cone filter hopefully makes the set-up more like a ram air design. This was why I also wanted the dual cone filter (no cap on the top of the filter).

<img src="http://img465.imageshack.us/img465/4025/219060116xa.jpg" alt="Image Hosted by ImageShack.us" />

This third pic is just more of a close-up.

If anybody has any questions, please feel free to post. Heck, if we all get better gas mileage because of this, we might all save some money, create less greenhouse gases, save stress and money not having to buy a smaller/another car and maybe get a little mlore enjoyment from the soccer mom rig!

 

Gosh darn it. I can't seem to get the pics up for peeps to look at. Help anybody?

 

Here is the code for images:
[IMG]URL[/IMG]
Does K&N make a cold-air intake system for a 1999 Grand Voyager with the 3.3L V6?

 

If they make one specific to the Grand Caravan/Voyager, I've never seen it. That's why I fabricated my own. If someobdy finds it, let us know!

A for the latest on the results of my effort...

I am noticing what seems to be about a one-to-two mpg improvement on average. That would be approximately a 10% increase in avg mpg. Not bad for home tinkering. I also believe that I have better throttle response and that the engine revs more easily in higher rpms because of less restriction (no, I don't race my mini-van nor do I always stomp on the gas pedal).

What I have noticed is that when going up a steepr hill in my area, it seems to handle the hill better and I get the impression that in the higher rpms it's not working as hard and handles the slightly higher rpms range better.

Hopefully, I will take it on a relatively flat trip (not over mountain passes) soon and report on my mileage.

I like my van more (that has to count for something). I figure that anytime i can do something to my van that makes me like it more, makes it runs better.... That's a good thing![8D]

BTW, is there anybody on the forum that would be willing to allow me to e-mail my pics to them and post them for me? I'm still having difficulty with that. I know, I know......