Well.. then.. that would be effectively a COLD AIR BOX.. with no filter on the end... I think keeping the filter on the airbox and keeping the carby airhorns free of clutter would be better...

In addition...

The carby mounted airbox moves with the engine...It stays sealed to the carbys...

The use of ducting in place of a real airbox will be divorced from the engine and prone to hot air leaks from the engine bay...

I'll tell you how sensitive the system is...

Notice in this picture i have removed the hose and simply stuck the filter on the front of the sirbox...

The heat from the radiator is enough to completely change my mixture on hot days... with the hose hooked up and the air filter in front of the radiator... the problem is GONE!!!!

and another point about the Rebello CAI... that works fine for a race car that is in constant high speed motion... but for a street car you need cold air when moving slowly or at a stop...

The street benefits are a more stable idle and more consistancy during part throttle stop and go traffic conditions...

You will also find that jet changes are not neccessary for small ambient temp variations... I only change jets for summer and winter... otherwise I use the same jetting for a wide range of temps... that was not possible before the CAI... I have found the jetting to be MUCH more sensitive to temp changes without CAI in general for a variety of carbys...

Not wishng to add any further fuel (pun not intended) to the discussion but.... don't internal combustion engines work like this. Please correct me if I'm wrong. You know, always learning and all that.

O2/fuel mix enters the combustion chamber and is burnt. The more fuel and O2 you get in there, the bigger the burn, therefore the piston moves down the bore faster = more grunt.

The O2/fuel ratio is set at a constant in the "ideal" world but in the "real" world it changes due to pressure and temperature changes in all cars. FI handles this alot better than carburation. Carbs are tuned to the "local" conditions to get the best out of them.

So isn't it safe to assume that the more dense the air, the more fuel you can get into the chamber to achieve a bigger bang.

Surely there must be an advantage in using cooler air than engine bay air. Maybe a very small one but measurable. How obvious is it to the average zed owner driving out (locally without driving up mountains where large pressure changes are expected) and about is probably neither here nor there, but in racing where every little bit counts then sure, I would think that cold air would be vital.

If not then why use cold air induction or intercoolers on turbo engines.

James

I agree that the difference uses (street vs track) will/would indeed make a CAI more attractive. My earlier post was in response to a question I had asked Dave recently. I was passing this on. No offense was intented. I do really like your box (no pick-up line intented either)....

So two questions.

1) Having access to a metal fab shop would you share plans for the box (perhaps a barter of some parts - www.baddogparts.com - I know the owner)?

2) What is the line coming/going to the individual intake legs? I run a common tube for my brake booster since one leg doesn't generate enough vacuum. Is this what you are doing?

yes... that is vacuum porting because I do drive that car on the street... and it has a high overlap cam installed... The 45mm carbys with that cam make very little vac at low RPM...

I would NEVER construct an aluminum box like that again... The metal fatigues easily.. I have been forced to remove and reweld many points on that box several times...

The Fiberglass box from TWM is FANTASTIC... the prefab FRP box is worth every penny... and it LOOKS GREAT!!!!!

Yeah, looking at that TWM box is what got me to call Dave. The price is awesome too, however.

I am most impressed with nearly everything that TWM produces...

I guarantee that the TWM airbox is worth every penny... PLUS!!!! the TWM airbox can be ordered with the mounting panel precut to fit the Weber triples on the 240Z...

I will get you some measurements of my aluminum box if you would like... but I would reccomend running far far away from the idea of an Aluminum box...

Yeah, if I had more money when Dave was building my engine I might have been inclined to go the EFI w/individual throttle bodies but adding in those costs and an engine management system would mean having a great running and higher hp motor but no suspension or brakes.

I'm on the fence about buying the box (I have their intake and linkage set-up) and will see how the overall cost of my replacements and upgrades for '07will run before ordering one.

I agree that 'cold air' (air other than in the engine compartment) would be better. I was referring to the gentlemen that had a ram air on the hood going down to his fi...I was think about SUs in the same manner that that isn't going to help--ram air on Su's. I worded it real bad. Forcing air into SUs has no benefit I should have said.