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Hey dudes, just read this thread about doing the cold intake and exhaust and it was excelent! I have the DOHC and am thinking very seriously about doing these, like you say I don't want to go faster just a bit more responsive with a nice exhaust note. I know you've just spent 5 pages hashing this out but a question I have is whether you could leave the stock set up there and modify the stock air box bottom etc and mount the K\N filter through the bottom of it, as you's have done?
Ok you don't get to have the pretty coloured pipe but it's just a thought I had while reading it, I haven't even pulled anything apart yet, so there might not be the room or what ever.
Like I said this was well worth the read and apart from some window tint maybe a set of mags rather than the factory alloys, which I don't hate, is all I want to do to it.
 

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From what i've heard the CAI does the same as exhaust it moves the powerband to the top hence above 3k rpm. What i think has to be doen is like what you said a modified airbox with a cold air inlet. Reason for this is that the stock airbox might act as a resonance chamber. I have found more then a few places where mazda uses this concept on the 929.
 

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I also considered making a cold air box on the 929, it would be easy. I would also consider using a 3" cone filter inside the box instead of a panel filter (more surface area).

Since the air intake box already pulls in air from the grill area, you would have to seal this hole off. I would cut a hole in the bottom of the air box and also cut a hole just underneathe it on the inner fender. From there jus make sure you can seal it off and use some ducting to draw air in from the behind the bumper now. This should work as its own resonance chamber and perhaps improve mid range torque.
 

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I was looking at the same thing because the box does have an resonation chamber but my cone filter didnt fit, and... let me go look at the old box to refreash my memory.
OK, now that Im looking at it I remember, the resonation chamber turns the inside of the box to a V shape and the cone hit the sides. The V shape also, combined with the indentations on the rear & right side (for components around the box), makes the bottom small (1 1/2”). I thought about molding a new bottom section w/ fiberglass, inserting a new, larger dia. inlet but I hate working with fiberglass. I know the engineers made the made the chamber based on wave frequencies and all that shit, but the air inlet to the box looks like an afterthought. Its sloppy, small dia., thin walled, and runs over the hot rad. Like, oh fuck! We ran out of room!

Im sitting here playing with the box and thinking, what if you spun it around so the chamber is on the right side and the inlet is right next to the fender well. The clips to the top don’t match up but that would be an easy fix. I might play with it this weekend because Im tired of being scared to drive in heavy rain.
 

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what ever happened to that guy pomes?
 

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Ive driven in rain for 4 years, no problem with a CAI, and trust me in Vancouver it RAINS. Im confused on what you are describing on the HD intake as Im not familiar.

I think Pomes was happy with his car and didnt need to post anymore...

back to intakes... ...my filter basically rests on the bottom splash gaurd. I have fabricated a small splash shield on the back where it is exposed to the tire well (it was the location of the OEM intercoolers).
 

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Yea, lived in Seattle (in fact my state of residence) for 9 yrs. The diff between northwest and the south is the the roads are made to handle the rain in the nortwest. Here in Savannha, you get shit from the atlantic coast or florida and all of the sudden, two inches in 30 min and standing water. If your not paying attention (or get forced) your diving in that big lake in the road and your screwed. The box has to go back on before spring, or a diff filter location, its not worth the gain, havent noticed much anyways.
 

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Then you deffinetly know whats up in the Pacific Northwest. But I have to agree with you, the weather and storms on the east coast are crazy (Halifax gets wrecked by storms). For you it would so be worth building a intake chamber thats flexible enough to change for the seasons. It wouldnt be hard, you might even grab some TQ.
 

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Did the intake again, due to the big lake I drove in two weeks ago. The box was not an option because of my relocated coolent reservoir. Moved the MAF up (back to normal pos), had it low, tip of it inside the fender well to get good temps. But a few degrees vs. water in the system is a good bargain. Overall, lifted the filter (in fender well) two inches and the system is much better cosmetically. Made a new splash guard too.
 

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dang--I need to do some research. I live in a place where my car has to pass emissions. I do not know if I can even remove the muffler and still pass.[/b]
i have a 3.0" aeroflow muffler http://www.aeroexhaust.com/aero_turbine_xl_3030xl.html that i welded to a split to 2.5" pipes and i was gonna run custom 2.5" pipes to cats i wanted to know if i should get hi flo cats or which to go with w/o loosing bp?
 

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Are you from Cardomain ?

Im not a fan of those 'gimick' mufflers. You might have already lost HP some low end TQ with what you've done. If you spend some time reading previous threads discussing set ups, you would of already known that our 929s are picky when fitting custom systems. Personally I think 2.5 is too large and will result in low end TQ loss. I am though interested in a sound clip if you have one availible. There might not be enough back pressure with hi flow cats (there might not be enough now). Again, I will mention that an 'X' pipe would be nice for our DOHC's, restoring back pressure & smoothing out sound.

How do those mods feel right now ? Did you notice harder pulls to redline but less grunt down low ?

If you are the same dude, then You asked what 90-93 Accord parts I used. I was tryin to state that I cut up a short ram Accord intake and made it fit for the perfect CAI.
 

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I'm sorry to bring this back up but I just got out of school and I got time, money and questions.

1. From the type of driving my dad does and the auto box this car rarely sees anything above 3k. Will I get any gains from a CAI or should I keep away from cutting holes in my fathers car.
2. In the manual it says something about a water thermosensor detecting the coolant temperature and sending a signal to the ECU. Can I use this as an auto switch for an electric fan or can I swap it out for a fan switch
3. Our exhaust system is rusted through. I'm planning on taking the old pipes to an exhaust shop and getting bigger pipes, bigger cats, and twin mufflers where the large muffler is located.

biggest problem is I need to keep the car quiet(er) and vibration free cause my father is old and old guys and loud exhausts is a no no.
 

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?
 

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ok everyones having fun with thier 929's except for me :angry:
 

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Here is my C.A.I.
[/b]

i was thinkin about making that intake pipe before the air sensor way back. did the intake resonance get louder with it ?
 

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Not really you just hear the sucking louder and you get a better take off and your intake pipe never get's hot any more

I had the CAI for a while from my old honda I just cut it and pieced it together

Duce what did you mean when you said you put a bottle cap on your resonance tube

I wonder if you take the two hose off comeing from the IAC valve and the vavle cover and put small filter's on them and seal the whole intake off would it sound and run better
 

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i meant that on the DOHC system you could cap off the resonace chamber. the single cam doesnt have one. im not sure if you could put breathers in place of those two hoses.
 
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