If you look a few posts up from the bottom of page 3, you'll see a picture of what I ended up doing for the screens. I used stainless mesh, same kind as C5 Z06's have in the front.

The plastic sheet in front of the radiator including the metal X - brace both have to be removed if you use air-boxes like mine.

However, do not remove the lower air-dam / radiator air deflector because your car will over heat if you do so.

Okay listen this setup is not a cai although it does incorporate its features it is a ram air setup, what makes a ram air is not forcing the air from the outside directly into the cylinders, but instead of the engine sucking in the air via the intake, the air is being forced into the intake, and the faster you go the more psi is attained, thus it is a ram air system not a cai which is a filter on the outside of the engine compartment that allows the engine to still pull the air itself, dont get me wrong cai are good, but this is a ram air setup

ill explain why in detail:

we all know that the engine draws in air via the intake, we place a filter to prevent anything other than air passing through, but with this setup instead of allowing the engine to constantly be starving for air and having to pull in its own air causing power loss. This setup takes the outside air and forces it into the intake and because your intake has a limited opening for the air to enter psi is attained, the faster you go the more air you are ramming into that small space creating pressure and compression as all the air cannot enter at the same time. the reason it is pulling so much better at higher speeds is because you are feeding essentially compressed cool air into the intake, otherwise known as the Ram Air System!

Sounds like Ram-Air to me. But just to be sure, you should do some back to back runs to 100MPH with the ram-air in place, then with just CAI in place to see the difference in KPA. That would settle this.

Also, do you see the same gain with air filter in place?

I only made a couple of runs on the LM1 / 2-bar map combo, it was borrowed from a friend. The runs were made without the air-filters, if I remember correctly...

You can definitely feel the difference with the boxes in and out on my car. I left them in!

Posting to this old thread just to share that I finally got busy and just today built my ram air boxes. They went together alot like I had envisioned 11 years ago. I used 20 gauge aluminum sheet and glued the sides of each box together with flexible cement with 3 rivets per seam for extra strength. I'll make a thread with pictures at some point. I am very pleased with how they look and fit. Next to be modified is the air lid, for higher flow.

I have the IROC beast down for a series of upgrades this year, including a sweet set of brakes from Ed at Fly N' Bye. I cant wait to see how these boxes and the modified lid work. I expect a big gain at higher speeds.

Thanks for keeping us up to date on this. I have been wanting to do this project for some time now. My car is TBI. My hold up to this point has been getting beyond the TPI filter housing and back to the throttle body...

Speedy

Have you looked at the air inlet tube on the GM Vortec? Im thinking pick ups around 94-98, perhaps more years than that. They had a plastic tube running from the cold air port and air filter housing to the throttle body. With some plastic tubing to fill the gap, I think this housing might work for you.

I just drove the beast for the first time yesterday since building the ram air boxes and high flow air lid. WOW! What a difference. I could feel a definite improvement at 25mph(notably more tire smoke and butt to seat grabbing). The same improvement at 45mph(fairly scary). At 60mph on a full throttle manual downshift to 2nd, was where the difference really came to light.

I had to be quick to avoid hitting rev limiter at 7,000 before grabbing 3rd gear. I've been used to it getting there pretty quick but now it's even quicker. Hitting 3rd gear, I was gripping the wheel tight as I shot past 100mph. That's the positive pressure introduced at the plenum from the ram air boxes, made more effective by the high flow capacity of the new air lid. I am very pleased with this latest upgrade.

I also had the opportunity to complete the AC delete process and clean up my original wiring from 12 years ago. Cant wait to run and show her this summer.

So do you have pictures and dimensions of the boxes? You know like picture inside that plastic Y piece, one from the outside. Actually can you just draw up like a blue print type of thing with the dimensions written along side. I got a project coming up that we plan to put a 383 in and I wouldnt mind doing it to my Iroc either!

I would paint the INSIDE black and polish the OUTSIDE. The black paint will absorb heat from the ambient air and the outside will REFLECT away heat. Should drop your intake temp...

I will take some photos soon. for now, look through this thread for 1Bad91Z's original design ideas. Also, look for his air lid modifications in his High Flow Airlid thread. For the airlid, I just plagurized his design. The ram air was more difficult as there are no clear designs available. Mine are all assembled now so even photos wont help much. You just have to remove the panel between the opennings in the front valance, remove the fog lamps, cut the bottoms out of the filter housings, and fabricate boxes to fill the space between the housings and the ports in the front valance. I used aluminum sheet for mine.

It all depends on application of course, but wouldnŽt it make sense to make the air boxes in the nose cone a two layer design?

Top layer for the ram air, and a lower layer leading air directly to the radiator, giving both boxes about half of the available space.

Personally I have been thinking about fabricating something similar to the airboxes featured here, but I keep wondering how much air the engine really needs, and if only part of the available area in the nose cone would suffise for that.

I think IŽll have to give that a try.

I suppose that would work. My intent, as was 1bad's, was to transfer the pressure created against the front of the body at high speed to the air intake. Anything we can do to increase airflow to our TPI engines will result in increased power. On installing the ram air boxes, I saw that there is more than adequate air flow to the radiator. Especially with the radiator air dam in place.

In my case, I also deleted the AC from the beast. I had removed the compressor two years ago to make way for the Moroso vacuum pump. So it was natural that I should remove the condenser from the front of the radiator and install an AC delete box. I found the space between the condenser and rad half full with leaf fragments and other debris. Obviously, with this and the condenser gone, the cooling system will work much better. My 355 has always stayed cool anyway(160 t-stat and fans on at 180). Even with the car lowered 2".

ok, my car is equipped with TBI, and I pretty much intend to keep the TBI unit on there, use an open air filter element and feed that with cool air. I think for that purpose (no ram air effect, but same space to work with) I will not use the TPI filter setup, but rather fabricate a cool air duct using the available space instead.

My car is lowered 2" which does not allow me to run the stock airdam without losing it on parking in my garage. I fabricated a somewhat shallower but wider airdam. The car will go up 1" somewhere next month so I will then fit a larger airdam. Maybe just the stock one.

I also considered A/C delete, so thnx for that bit of info.
Losing the condenser should indeed do a lot for cooling.

I will start with taking some measurements this weekend and see what to do, but I will definately save a link to this fabrication thread because I love the idea of using the nose cone more effectively.

Ive felt from the first time I ever worked on an IROC that they were intended to have ram air from the factory. I figured some bean counter just pulled it to save a few dollars. The location of the ports in the front valance are perfect for ducting to the IROC filter housing. I understand if you choose to go another way. I love the way this upgrade turned out.

To that I can only say


Might have to consider building the setup in a way that will allow me to use one of these Spectre elbow pieces to gain a ram air effect on my TBI

I just think it can be done more effectively then using the stock TPI air filter assembly.

The nose cone definately appears to indicate the original intention to fit such a setup by default.