The previous owner had a drop-in flat K&N in the stock airbox. I wanted something less restrictive but didn't want to spend $300-$400. To get an improvement from any intake we must increase the airflow (CFM) and decrease the temperature.
I chose a Spectre PROFab 9932 - they are on sale at Summit Racing but even cheaper at Amazon.com. I picked mine up at Amazon for $112 shipped. It took me about two hours last night to install it. I wasn't in a rush and I stopped frequently to admire my choice in beer.
Spectre claims 12 HP gain - they have dyno sheets and other useful info on their site. YMMV
I already have a Flowmaster cat-back installed. I thought the tone in the cabin was fine with the stock intake - but out it came, hoping for more MPGs.
My first bit of testing is all seat of the pants - but I'll get to work on the sensors and data acquisition stuff later. I was just too excited not to install it right away.
First impressions -
I'm very impressed with the materials and quality. Everything was exactly as I expected them. The fit is excellent and the instructions were exact. The only thing that didn't work for me was re-locating the washer fluid reservoir pump and level sensor wires through the hole in the heat shield as they suggested - the wires aren't long enough. Didn't matter in the least anyway.
Sounds great - Awesome gasp when you stomp on it and a good tone through the RPM range. Certainly more engine noise in the cabin.
No low end gain - didn't really expect that. I would say that there is a tiny bit quicker response when you stomp on it from idle, but no difference in stomp response in 2nd or 3rd gears - while at steady RPM. I'm not really all that impressed with the throttle response but that's for another thread.
Better passing power - I do have more power when I get it wound up. I haven't highway dragged with anyone yet to really tell the difference in roll-on but I wasn't disappointed on my way to work this morning.
MPGs - Don't have enough data on that. I've driven the last tank very conservatively and I got 345 miles out of it with 91 octane and with Lucas injector cleaner until my DTE read zero.
Ok so all this is very subjective and you want some data and pictures I'm sure. I don't have access to a dyno and I don't go to the track for slips.
However, since it comes down to air-flow and air temperature, I can measure those parameters along with throttle position, rpm, outside air temp, engine temp and fuel pressure. What else would you like to know? I can probably get timing data as well but I'm not sure which sensors to tap into for that yet. I won't be going through the ECU to collect this data, it will be either from sensor taps or from my own sensor installations.
Now that it's installed and I kinda know how it feels, I'm gonna pull it back out and drill at new hole for the IAT down at the filter. If the computer thinks the air is cooler than it actually is at the TB then it will advance the timing and add some fuel to compensate for the denser air. I'll measure the differences in temperature to know exactly what the IAT is seeing in both places. This seems counter-intuitive for MPG increases but if it takes fewer HP to drive the same conservative manner then it would follow that it should take less fuel to do so as well. This can't be worth more than a couple percent and this effect will be negated by a programmer anyway, so we'll see.... fun to find out for sure though.
The intake is polished aluminum so it's technically conducting engine heat to the air flowing into the TB. A future test will involve insulating the intake tube. HOWEVER, air flowing at anything more than idle doesn't have much time to get heated from the intake tube. The surface area of contact is actually quite small for the volume of air flowing through it. Exactly opposite of the effect through a radiator, which has a high surface area to volume ratio.
That's all I got for my lunch break - Have a great weekend!