My cold air
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My cold air
Not to discern Tree25?? but here is my cold air. I got the heater ducting from a local hardware store () pm me if you want to know where. It only cost $5.99 too, but cant say where. Any way, its an easy mod if you have the tooling. I was able to leave the overfill in the stock location. Its a 3" duct.
Last edited by Steve Shulz; 01-16-04 at 09:31 PM.
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how could i go about making a cold air kit for a weber 45 dcoe? the intake just sits right on top of the block (not the coolest air)
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Re: My cold air
Originally posted by Steve Shulz
Not to discern Tree25?? but here is my cold air. I got the heater ducting from a local hardware store () pm me if you want to know where. It only cost $5.99 too, but cant say where.
Not to discern Tree25?? but here is my cold air. I got the heater ducting from a local hardware store () pm me if you want to know where. It only cost $5.99 too, but cant say where.
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I ran a cold air intake on my car (not the Rx-7) simply by taking my breather off and going to autozone. I picked up a 2 1/2 to 3" adaptor clamped it to the top of the carb and ran PVC pipe down to a cone filter. The carbs on the Rx-7 are most likely a bit bigger, measure it sometime and try it out (most likely 3"), not really any power gains, but sounds cool and cleans up the engine bay.
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Gregs, you would have to read Tree25is' thread cold air intake with pics thread to know where that came from. Didnt notice the car running cooler, did notice that when stopped in traffic it seems to breath better. Would say a minimal hp increase, just looks cooler. Was hoping to get a little ram air effect as well. It definately is cooler than engine bay, major icing probs with the onset of winter, then I remembered I had the hot air duct taped off. When summer hits I'm going to remove or have the flapper in a closed position, cant do it now though.
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For all of us that just like to look and not click...
I think I stumbled upon the reason why you're not seeing as dramatic increase as you were hoping for. The square hole that is in the air cleaner base itself (where the air cleaner horn is spot-welded to...) has dimensions that essentially are equal to a tube with a 4" ID. Anything less than that diameter tube and you are keeping the significant airflow restriction that the air cleaner horn represents, even though your cold air tube is larger than that horn. FYI for all the CAI gliterati out derrrr...
I think I stumbled upon the reason why you're not seeing as dramatic increase as you were hoping for. The square hole that is in the air cleaner base itself (where the air cleaner horn is spot-welded to...) has dimensions that essentially are equal to a tube with a 4" ID. Anything less than that diameter tube and you are keeping the significant airflow restriction that the air cleaner horn represents, even though your cold air tube is larger than that horn. FYI for all the CAI gliterati out derrrr...
#13
Airflow is my life
Ok, and now for something completely different.
J/k
Mario your in the right track, that would help also. Its the plastic flapper thats causing the restriction. Trust me, my flowbench doesnt lie.
J/k
Mario your in the right track, that would help also. Its the plastic flapper thats causing the restriction. Trust me, my flowbench doesnt lie.
#14
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Your set up will actually hurt your carburetor performance. With you trying to ram air into a carburetor you are forcing air in, which works fine for fuel injection.
I tried a simular setup when running PRO7 and saw my lap times drop, so I turned the air inlet to the left (across the car) and my times went up.
Another problem with your setup you will pull in a lot of the dirt and water into the intake tube.
I agree the fresh air is what the engine needs, but the carburetor will need to pull it in, not to be forced in. Very hard to duplicate on the dyno machine, but repeated testing at the track showed to me that forcing air in was not helping.
John
I tried a simular setup when running PRO7 and saw my lap times drop, so I turned the air inlet to the left (across the car) and my times went up.
Another problem with your setup you will pull in a lot of the dirt and water into the intake tube.
I agree the fresh air is what the engine needs, but the carburetor will need to pull it in, not to be forced in. Very hard to duplicate on the dyno machine, but repeated testing at the track showed to me that forcing air in was not helping.
John
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Gotta argu that! There is a trade off somewhere since cold air is more dense than hot - what is the trade off, lot of factors, altitude, humidity etc. Im still perplexed on what Mar3 said (thanks for the pic post info) about area coming to be 4" ID, this is a 3" duct and it fit perfect, and the snorkle end is like 2.5. Now I know the dynamics of tubes with divergent vs convergent design (jet engine mechanic 12yrs USAF) and that design will create pressure increase/velocity decrease at the expansion point, but this is all on the theory of air being pushed and in this case its being pulled [edit]feel its the same-only change I ever heard of was at supersonic speed the theories are reversed[edit], further conveluted by the air cleaner assy and air filter itself. Now in perspective, this is a car and the total increase I could be getting is minute at best, I'm not making a living on this, so its just fun to tinker.
Last edited by Steve Shulz; 01-17-04 at 11:17 AM.
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Have you ever seen a fast car with duct work from a home improvement store hanging out the front of it? I'd suggest buying a mushroom filter from eBay, taking off the air breather assembly and clamp the mushroom to the top of the carburetor.
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That would be the best (air flow wise) I agree! And yes I have seen super fast cars with a duct hangin out the front. Skylines, Sylvias, 180 sx's, Hachi Roku's, you name it. You know, the place where the "Rice" comes from, the elusive j-spec cars. Seen a really cool MR-2 with a periscope duct on it too!
#20
Airflow is my life
Originally posted by Steve Shulz
Gotta argu that! There is a trade off somewhere since cold air is more dense than hot - what is the trade off, lot of factors, altitude, humidity etc. Im still perplexed on what Mar3 said (thanks for the pic post info) about area coming to be 4" ID, this is a 3" duct and it fit perfect, and the snorkle end is like 2.5. Now I know the dynamics of tubes with divergent vs convergent design (jet engine mechanic 12yrs USAF) and that design will create pressure increase/velocity decrease at the expansion point, but this is all on the theory of air being pushed and in this case its being pulled [edit]feel its the same-only change I ever heard of was at supersonic speed the theories are reversed[edit], further conveluted by the air cleaner assy and air filter itself. Now in perspective, this is a car and the total increase I could be getting is minute at best, I'm not making a living on this, so its just fun to tinker.
Gotta argu that! There is a trade off somewhere since cold air is more dense than hot - what is the trade off, lot of factors, altitude, humidity etc. Im still perplexed on what Mar3 said (thanks for the pic post info) about area coming to be 4" ID, this is a 3" duct and it fit perfect, and the snorkle end is like 2.5. Now I know the dynamics of tubes with divergent vs convergent design (jet engine mechanic 12yrs USAF) and that design will create pressure increase/velocity decrease at the expansion point, but this is all on the theory of air being pushed and in this case its being pulled [edit]feel its the same-only change I ever heard of was at supersonic speed the theories are reversed[edit], further conveluted by the air cleaner assy and air filter itself. Now in perspective, this is a car and the total increase I could be getting is minute at best, I'm not making a living on this, so its just fun to tinker.
#21
Airflow is my life
Originally posted by O 16581 72452 5
Have you ever seen a fast car with duct work from a home improvement store hanging out the front of it? I'd suggest buying a mushroom filter from eBay, taking off the air breather assembly and clamp the mushroom to the top of the carburetor.
Have you ever seen a fast car with duct work from a home improvement store hanging out the front of it? I'd suggest buying a mushroom filter from eBay, taking off the air breather assembly and clamp the mushroom to the top of the carburetor.
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Originally posted by Rx7carl
Yea, look under the hoods of cars at the road course near you. Just cause its doesnt make it fast.
Yea, look under the hoods of cars at the road course near you. Just cause its doesnt make it fast.
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