at the minute i have the stock rubber pipe from the tb to where the airbox was. i replaced the airbox with a small-ish section of alloy tube with a little bend on the end and put the filter on the end of that.

im just wondering if i could do away with all the intake pipe and just mount the air filter directly to the tb and maybe run an air feed to it or make up some heat shield for it and shim the back of the hood up a little.

theoretically this should improve throttle response and make the intake slightly louder. anyone tried this before?

 

I used to have the air filter mounted on the throttle body of my old B16A Civic. It had decent throttle response but it did not pull as hard on the top end as it would have if there was a short ram. Heres a pic

 

it was a tight squeeze but i got it on. mucho louder and seems to pull instantly. not sure about top end tho because i only took it for a test flight down the street and couldnt get to the top of 2nd and 1st just spins like a biznitch. from my experience doing home made intakes for my other cars id say the reason it didnt pull as good up top was probably because the filter was taking in more warm air than if it were sitting tucked nicely behind the headlight.

im not sure if i prefer it this way or the way i had it. gonna leave it on the tb for now anyway.. ill see what its like tonight and make my mind up if i want to keep it this way or not.

with the old diy setup ithad a nice grumble thats turned into a big roar with the filter ion the tb. it seems to have lost the neato sound it had before when pulling from the low-mid revs up to the limiter. i think it has anyway, didnt drive it enough to be sure. it had a nice change in pitch before at about 4-5k (best way to describe it i guess).

 

also wtf is that stupid plastic pipe thing that goes into the bottom of the standard rubber intake pipe? i followed it under the distributor and it just tapers down and is bolts to the engine on the front corner. its not for sucking warm air off the exhaust manifold anyway because it doesnt reach that far and the end that is bolted down has no opening.

 

When I bought my rex it already had the filter right on the tb (just like in your pic). I made an intake pipe to relocate the filter where the old filter box was. Then I made a pipe to catch air coming through the fake port in the plastic front end (I cut it out of course). Its hard to say it made a difference without something better than your butt dyno, but I was getting cooler outside air to the filter. I wish I had taken pics when it was still together.

I read in an import magazine a few years back where they had a full length intake pipe (the kind that puts the filter down by the road outside the engine bay), a short ram type (the most common kind putting the filter by the battery), and finally putting the filter right on the tb. They used one car on a dyno. The short ram had the best mid range and the full length had the best top end. In none of the tests did the filter on the tb get better numbers.

I will be rocking the short ram personally, but I do like the louder intake sound you speak of.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DmcL &raquo;</TD></TR><TR><TD CLASS="quote">also wtf is that stupid plastic pipe thing that goes into the bottom of the standard rubber intake pipe? i followed it under the distributor and it just tapers down and is bolts to the engine on the front corner. its not for sucking warm air off the exhaust manifold anyway because it doesnt reach that far and the end that is bolted down has no opening. </TD></TR></TABLE>

The one is for condensation to drip down into.

 

i see...

i thought it was some crazy expansion chamber type thing lol

about the filter setup.. even with my trusty butt dyno i can feel a difference between a home made short ram and a fully fledged CAI, again home made

i think the reason for the lack of top end with a filter on tb setup or short ram is the fact that the filter is taking in alot of warm air, the shorter intake length sharpens response at the expense of air temp. would also explain why CAI's suck for throttle response but rock when the revs start to climb. guess all those home made intakes have taught me a thing or 2 afterall lol its all good tho, this setup along with the previous setup are only temp anyway untill i can make a nifty home made intake that will hopefully have good throttle response while still being fed colder air. just not sure if i want to use my cone style shielded filter or if i want to steal the sealed cf filter and run an air feed.. dunno yet, not much room to play with the battery right there in the way.

 

the way i look at it is,
when you see well built cars pushing high numbers, do they have a filter mounted to the throttlebody with a heat shield?
nope.
im sure someone would have thought of this by now, and i think theres probably a reason they dont do it.