[phu82]

Hey guys, I have been thinking about making a homemade intake for my 4.0 ZJ using some tubing and a K&N conical filter. I need some opinions.

What do you guys think is a better material to make the tube out of: PVC or Metal. I have noticed that many other people perfer to use metal but I would think that PVC would insulate against the heat better than metal because metal is a better conductor of heat.

Next qustion is: will it be ok to leave the bottom portion of the factory air box in place and place the intake directly over it? Would the the bottom portion of the air box provide any benificial insulation.

And finally: Will using this homemade intake with a conical filter provide much more performance over using a drop in k&n filter. Afterall its in the same location. Is it basically the conical filter that is providing the benifits?

thanks

thanks

 

[Big Dumb White Guy]

go with steel tubing. electrical conduit works great. you can always insulate it.

the tube that allows the air thru the grille is restrictive. yank that sucker and cut that flap (pierce of rubber), too. as for insulation of the filter. start with cardboard and make yourself a box. then use that to make 1 out of sheet metal. i've wondered if plexi-glass would work too. it can handle quite high temps. plus if you insulate that.....? i've done the cone filter and tubing, just haven't gotten around to making a box yet. haven't noticed a problem yet. think about it. your fan is drawing in cold air, and usually when you need the power, there's a good chance you're already moving.
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herbalaire

 

[ATL ZJ]

I made mine out of PVC, after searching for the electrical conduit that Big Dumb White Guy told me to use. Make sure it has a 3 inch outer diameter and is approximately 6 inches in length. Use a conical K&N filter model RE-0920. You must also allow for the two hoses that come out of the tube. I used galvanized pipe fittings for these. Measure the inside diameter of the hose to determine what you need, drill a hole, and screw it into the PVC. It's a firm connection, but I added epoxy to ensure that no air got out. It's really an easy install, made easier by removing the airbox. The difference in performance was noticable the first couple times out but I soon got used to it. I see the improvement in my gas mileage every time I fill up. I don't know where you could find electrical conduit; I looked everywhere, but for me the PVC worked great.

 

[Big Dumb White Guy]

it'll work (pvc) just fine too. i would look into insulating it when you get a chance. couldn't hurt. i found mine at work but you could check with an local electrical contractor. they should have it if they do industrial work.

btw i used 3.50 diameter conduit. i know that some engines have a smaller tube. we don't have emissions testing here (yet), so i didn't worry about all the extra tubes. i just capped them off with a small filter.

when you're done with getting rid of the air box, get your TB bored out. bring it to a machine shop and have them bore it out to 60mm. it's just that step below the butterfly. they should be able to do it for $30-$50. it should take less than 1/2 hr.

the money you just saved by doing this you could upgrade your exhaust. remember easy air in + easy air out = HP!!!
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vaporizer

 

[AP WJ]

I got everything to make my intake at home depot.

They're big pics so I'd rather not post them in the actual thread
http://www.vxpromotions.com/public/wj/intake.jpg
http://www.vxpromotions.com/public/wj/intake2.jpg
http://www.vxpromotions.com/public/wj/intake3.jpg

I wrote up something about making it a while back, if you're interested just send me an email and I'll try and find it. I'm sure the differences between I6 ZJ's and WJ's are minimal.

AP


[/img]

 

[Big Dumb White Guy]

OK AP. now i wanna pic of the battery set-up you have. how did you manage to turn yours? i want to do that.
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magic flight

 

[AP WJ]

That's the position the battery comes in stock on WJ's.

 

[Salzajeepn]

AP, I am interested in your setup, and am thinking of doing something similar with my ZJ. What materials did you use? Is the setup sealed from the engine at the radiator?

Salz

 

[phu82]

AP, your intake looks awsome, please send me and email of the write up if you can: phu82@hotmail.com
thanks

 

[SoCalZJPunk]

In addition to airflow has anyone devised any water prtection into their intakes..right now I have the small intake tube infront of the air box just removed until I decide what I want to do with it exactly.

I would love to get more air in and protect from deep water too.
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Breakup advice dicussion

 

[AP WJ]

Here's a little writeup from november, it's about half way down the thread

Sorry to link a ju thread... :roll:
http://forums.jeepsunlimited.com/ubb/Forum32/HTML/007343.html