Anyone know motorcycle air filter size for D15B4 carb mod??

[90civicGL]

Hey guys, looking at doing the carb mod on my d15b4 but in the mod write up I never saw any posts on what size ended up working in the end. Does anyone know what brand/size ended up working best?

[Baby Face]

K swap works best.

where is the mod?

[90civicGL]

I'd love a k swap, but due to P plate restrictions and the cost of one I'm going to have to work with what I have for a while :P

http://www.ozhonda.com/forum/showthread.php?13069-Dual-Carb-Modifications

Also does anyone know the laws of open filters in QLD? I'm presuming technically this would be illegal?

[Baby Face]

oh ok im presming you have dual carbs that lead to an air box before with a filter in it, and you plan to use pod filters instead of the whole box arrangement.

in this case just use a vernier to measure the Outside diameter of the carb inlet. then ebay search for pods that size?


as for what size to use i wouldnt know where to start... 54mm?

[tiksie]

Disclaimer: The following is provided as a GUIDE ONLY, and neither myself nor JDMST take any responsibility for the outcomes of someone else doing the following. You follow these steps at your own risk!


Aim: Make your carby more enjoyable! (quicker!)
Required:
10mm socket
Phillips head screwdriver/cordless
2 cone foam filters
Wire cutters

Please note this is done on a D15B4 twin carb motor in a EG GL Civic.

Filter inlet size by memory is 44mm
1.
Remove your twin carby lid which is held on by 4 clips.

Remove any hoses that are attached to your intake arm to make sure there is nothing stopping you from removing the whole airbox system off.

After that undo the bolts that hold the intake box in place, and then go ahead and remove the bolts that are holding the mesh/spacer to the carby throat.

http://img571.imageshack.us/img571/5751/s3pr50y1.jpg

After you have removed it all, you should be left with the following:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0207.jpg
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0209.jpg

Just give if a clean with carby cleaner since you have removed everything.

2.
Now, you will need a foam cone filter (or anything that you prefer thats open end) to put onto the spacer which will go back onto your carb throat.
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0213.jpg

The diameter you will need for the filter inlet is 54mm but you will need something that fits snug on it so take the spacer with you to the shop you that you are going to get your filter from:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0214.jpg

After you have mounted the filter onto the spacer, screw it back on with the 2x10mm bolts for each carby throat.

(please note that I haven't done this yet, but I will upate with photos once I have)


Next we will be doing the Keihin CV carb modification.

To do this you will need a phillips head screwdriver and a wire cutter, it's fairly simple to do and I did it while the intake box was off to give me some space to work with.

You want to remove the 2 lids that are right behind the carby:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0211.jpg
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0210.jpg

They are held on by 2 phillips head screws.

After doing that you will see a little black stopper (little plastic) in the middle of where the spring sits inside, just remove that.
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0212.jpg

After that you want to take out the spring which is sitting inside:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0206.jpg

And cut 2-3 coils off it (I cut off 3 1/2) so I was left with this:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0205.jpg

After that just put the spring back in with the uncut side at the bottom:
http://i408.photobucket.com/albums/pp167/tiksie/PROJECT%20EG/IMG_0206.jpg

And put the lids back on and just screw it back on and your done!




The springs control the rate at which the diaphragm piston valve rises when you push the accelerator. After the mod the valve rises much quicker, due to lessened spring density. This vastly improves throttle response. The plastic stoppers prevent the diaphragm valves from raising above a certain point, to keep fuel consumption lower. The higher the diaphragm raises, the bigger the needles open, the more fuel you get into your engine. The increased air from the cone filters and the fuel from the quicker lifting and higher lifting diaphragm means a cool 10-15HP increase (if you have a decently built engine already, otherwise, expect less)...


Filter inlet size is 44mm~ by memory (10mm smaller than spacer sizing).

Cheers

[tiksie]

If you want to upgrade later on, the DCOE45 webbers are perfect matched with a inlet manifold that's sold in south africa for around $150~ from memory.