Modified Stock Intake (NEW PICS Jan. 6)

Well I just started my first new project on the aveo in a while. I going to be doing what most people do to modify the stock intake to open it up but add a few different modifications to it. Before I go on with listing what I am going to do to the intake, I will say that I don't want any needless and negative posts, for example: saying thats pointless or not worth the work. Since its my project and my time I will be the judge of whether something is worth it or not.

My reason for wanting to do this is that I currently have a SRI, which is pretty much an aluminum elbow with filter. Its not very stable and as mentioned in other threads they rub on things near by like AC lines and some sensor. I can hear the rattle and it bothers me. Plus the sri is just sucking in all that hot air so I still want a CAI. But I don't want the pain of having to get to the filter in the fenderwell. So my best option I feel is modifing the stock intake box for better efficiency and flow. Now with that out of the way, here is my plan. First of all I am going to replace the stock filter with the K&N drop in. My resonator has been removed since my first CAI so I don't need to worry about that, but the little pipe that fits into the hole that opens up to the fender well with be cut to attach a larger 3" plastic pipe to allow more air into the intake box plus it will seal tighter in that hole to prevent it from sucking hot engine bay air. The bottom half on the inside of the box has a little bit of webbing will be left alone because the air is going to be turbulant in there and it still has to pass thru the filter anyway. The top half is another story. I am smoothing the whole inside of the top out and rounding out the exit to the intake pipe and making slightly larger. Pretty much I want create a funnel out of the box instead of the flush walls on the exit. The actual intake tube is still undecided. I might do an intake tube with the same kind of plastic as the box or aluminum. With the size, I don't quite know yet. I am thinking either 2.25" or 2.5"...the throttle body opening is pretty much inbetween those from what I can measure. I am leaning more towards the 2.5" because of something i noticed today. Has anyone really looked at the throttle body of an 04 or such (drive by cable)? I had my intake off and I felt inside towards the butterfly and it feels like the intial opening starts out smaller and gets a bit bigger towards the butterfly. This leads me to believe that it is quite possible to bore the throttle body opening out slightly. I will probably just get both sizes and see which works and fits better. But thats all I have for now, I just started sanding the top smooth tonight and thats going to take a while. I will update you guys with pics and info


UPDATE: 9/4/08 Pictures....I wanted to give nice big pictures so I just linked them from cardomain.
These pictures are of the top of the intake box smoothed out and filled in at certain parts
intake top 1
intake top 2
intake top exit
As you can seen in the pics for the most part I have it smoothed out. All the flat surfaces have been wet sanded with very fine grit sandpaper. They came out a lot smoother then I originally thought they would so I don't even need to spray it with anything to futher seal it. I still need to do the edges. Now the exit has been rounded off a bit but for right now I am leaving it at that. I might change my mind though and do some more work, but its a pain to get my hands in there and I don't want to take too much off and have it break.

these last two are of the bottom half of the intake box....those ridges were all over in the top but i smoothed that out.
intake bottom 1
bottom intake inlet
That inlet is what I plan to cut out and turn into a 3" inlet that wil seal flush with the fender well providing the box with only colder air from there and more of it.

I see you've put a lot of thought into this. I'm sure it will turn out good. Takes pics and post details.. I'm interested. Very.

sounds very interesting!! i'd like to see the pics also!!

i didnt want to read it all, it was startin to make my head spin, specially since i have forgotten what the stock intake box lookslike lol. anyway, id love to see some pics sam. when do u think u will have this done?

This is my original aveo trottle body. Its quite thick on the edges. I sharpen the edges for better air flow, less air boucing back. Performance, you definitely can feel the difference.

http://img512.imageshack.us/img512/904/bbtb01fb2.jpg

http://img244.imageshack.us/img244/2609/bbtb02bk1.jpg

i hope i can get the intake box done in the next couple of weeks. now with the throttle body, at first glance i didnt know what you meant xiaogary by sharpening the edges and bounce back, bu now i can see what you did which seems like a very good idea. Now with your throttle body, did you bore out the rest a little bit and have it funnel down to the butterfly size? If I did bore mine out, I would only bore the whole inlet to the exact size of the butterfly valve because boring out any bigger than funneling it down to the butterfly valve size would be pointless, seeing as only that diameter (diameter of the butterfly valve) of air can fit through it...

also can anyone comfirm what i felt with my finger, that the tb doe open up a little bit near the butterfly valve? where do you think i could find dimensions

Yes. Now the intake diameter is abt 3mm larger than the butterfly diameter. So there is a funnel effect.

When the air rush in or are sucked in, some of the air will be bounced back (creating turbulence and reduced intake air flow speed) due to the thick circumference wall of the trottle body. When you sharpen the edges, the air will be directed inwards, and less air are being bounced back (so less turbulence), higher air intake speed and better engine torque or trottle response.

And to further improve it, you can bore the whole trottle body to 3mm wider down to the butterfly and change the butterly fly to 3mm larger diameter piece of metal (only a circular piece of metal). But that would not generate much improvement as its the side thats the intake size. My mechanic told me if I were to widen the other side (manifold side or engine side) of the trottle body, it will have some improvment also (similar effect with using trottle body spacer), as there is more space inside to store air (increase air storage volume after trottle close).

xiogary, how did you hone out the throttle body to get it smooth?

Use a drill with grinding stone bit at the end. Use coarser stone to remove more material first, then use finer stone to smoothen it.

wait what??? how did you bore that throttle body out??? i def wanta do this mod. its easy it seems. never did that before. so maybe a little detail never did that before.

thanks