Mr. D, put down your glass & read this. Your house guests can wait.
12-05-2003, 07:34 PM
#1
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Mr. D, put down your glass & read this. Your house guests can wait.
I removed the duct tape from my original airbox inlet that mates to the air tunnel, & replaced the tunnel for use in conjunction with the ram air mod. OMG!!! It runs a lot better with both air entry passages. My baby climbs the tach & speed odometer like a cat on cocaine being chased up a tree by a doberman, compared to the stock setup. You can now return to your inebriation therapy.
12-05-2003, 08:08 PM
#2
what you're experiencing is a "low-speed" phenomenon only...
I have all the data on this but too tired to dig it up.
Basically the car is faster at low speeds with both intake tracts intact and flowing. However at 70MPH or so and up it's slower. The reason being you cannot build sufficient positive airbox psi with both intakes intact & open as all the air coming in the lower one will overcome the lower pressure coming in the upper intake tract and push air out of the original/upper intake inlet. You can only build significant positive pressure inside tha airbox at-speed with the upper inlet blocked off. That transition happens right at 68MPH on my car.
No harm done either way but with lower intake only you can get about 3psi positive pressure in the air box at 70MPH. With the upper intake open you have to be going almost 130MPH to build the same positive pressure. At 70MPH there's little more than ambiant atmospheric pressure within the airbox. But before the mod it was a negative pressure (vacuum).
It is louder with both open but it won't make as much high-end power. Hope this helps.
Basically the car is faster at low speeds with both intake tracts intact and flowing. However at 70MPH or so and up it's slower. The reason being you cannot build sufficient positive airbox psi with both intakes intact & open as all the air coming in the lower one will overcome the lower pressure coming in the upper intake tract and push air out of the original/upper intake inlet. You can only build significant positive pressure inside tha airbox at-speed with the upper inlet blocked off. That transition happens right at 68MPH on my car.
No harm done either way but with lower intake only you can get about 3psi positive pressure in the air box at 70MPH. With the upper intake open you have to be going almost 130MPH to build the same positive pressure. At 70MPH there's little more than ambiant atmospheric pressure within the airbox. But before the mod it was a negative pressure (vacuum).
It is louder with both open but it won't make as much high-end power. Hope this helps.
12-05-2003, 08:28 PM
#3
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Hey, thanks a lot! Definately makes sense.
I really need it more below the 70 mph mark because that's where I get on the gas the most (city driving). Now if I knew how to rig a door that would close the OEM passage at higher speeds, I'd be set! My car desperatley needs more power at speeds below 60 mph. I got outran by an S-10 from a stand still for heaven's sake. It was very very sad.
12-05-2003, 08:45 PM
#4
it's already in the works and activated at 55mph+ only via manifold switchover vacuum
But it may end up being too complicated to execute and expensive for everyone. In which case like the ram air I'll make the concept available to everyone
