"The Confines of the Engine Compartment"

[Andy Bettencourt]

I have never considered that intake to be legal for an ITA Miata. I believe, like RP, that anything flush or encroaching on the plane of the radiator sources from 'outside' the bay. That's oversimplified for sure.

[lawtonglenn]

I have never considered that intake to be legal for an ITA Miata. I believe, like RP, that anything flush or encroaching on the plane of the radiator sources from 'outside' the bay. That's oversimplified for sure.

I have always considered the engine compartment as a place where the engine resides. Clearly, the engine does not reside in front of the radiator, therefore, the engine compartment ends with the rear of the radiator. Non compliant.

+1

[Greg Amy]

I tend to agree with the above. However, re-read my post from above and tell me what you think...we're talking only an inch difference here...

Fair enough. So look at that photo of the item installed again. Note that the piece that extends well past forward of the radiator is the mounting system, and there's no limits to the mounting system for the air intake, only limits to where the air is sourced. If he were to trim back the top of that item, where the initial opening of the air source is, to a point right at the vertical plane of the aft edge of the radiator, would that not satisfy the letter (and potentially the intent) of the reg?

[gran racing]

The advice I'd give to that person is that it's quite debatable whether that intake is legal or not. They should also further look into whether there are truly any gains to be made. Then based upon those pieces of information, decide whether or not the hassle is going to be worth it. I looked into it after seeing that intake at Summit Point on the way back from picking up my Miata. I then spoke with ISC and a few other companies. I don't think that is a better option. I do know that every time I raised my hood in impound (do often regardless of whether or not required to), it would cause questions. Then questions about what else might I be doing too. It's also an easy protest that I have to imagine would come with a small protest bond fee. Curious, what do you think that would be?

After this simple protest is filed, it's then going to be a debate amount the powers that be just as being done here. Maybe found illegal then move on up to National.

Back to the real question, it sure looks debatable and right on the edge of the rules if it's not illegal.

That plastic cover near the rad. All year 1.8s have them? I don't recall ever seeing one on a Miata. I'll admit you made me go outside and take a look at mine. It's not there. For cooling purposes, I'd almost think it would be better to have it. My intake is not in that area and don't think there's any impact.

[Greg Amy]

>>> It's also an easy protest that I have to imagine would come with a small protest bond fee. Curious, what do you think that would be?

Nothing, just the $25 protest fee. Bonds are collected to cover the expense of any destructive inspections (e.g. engine tear-down) to reimburse the protestee if found compliant. In this case, there are no such costs.

>>> After this simple protest is filed, it's then going to be a debate amount the powers that be just as being done here. Maybe found illegal then move on up to National.

After the protest is filed, the Chief Steward will form an SOM to discuss the issue. They may ask for feedback from ITAC/CRB members. At that point they will present their decision. The protestee at that point can file an appeal to Topeka, at which point an Appeals Court will be formed to review the issue.

>>> Back to the real question, it sure looks debatable and right on the edge of the rules if it's not illegal.

Concur. Which is why I brought it here (with the permission of the original questioner.)

>>> That plastic cover near the rad. All year 1.8s have them? I don't recall ever seeing one on a Miata.

Yup, but it's a commonly-lost item. I think it's held in by a couple of plastic clips that are easily broken/brittle from time. Since we can replace the radiator with a sufficiently-large one, it's quite possible an advantage to 1.8L Miata drivers to "leave it lost" and allow cooler air to come into the engine compartment...probably a "weenie protest" item, unless coupled to something like this intake...but technically non-compliant.

GA

[JLawton]

I think you have to also look at the intent of the rule(s). From that perspective I dont think it's legal.

[Greg Amy]

I think you have to also look at the intent of the rule(s). From that perspective I dont think it's legal.

I concur. In my opinion the intent of the reg is to allow opening up of the restrictive stock air filter systems while avoiding allowances of things like ram air, cowl induction, and cold air intakes. We subsequently opened that further by allowing anything upstream of the throttle body/MAF/etc.

On the other hand, all air comes from outside the engine compartment, and it has to get in there somehow. We're seeing cold air boxes and radiant and convective heat shields around air filters and intake tubes to minimize the heating effects of the engine compartment.

With that in mind, how does this fit into that mindset? Is it incremental, and if so, within the boundaries of the intent? Or is it revolutionary to the point of being extra-compliant?

I dunno, that's why I'm asking. But at this point, ignoring the value of it, I'm thinking if you trim back the upper edge of the rectangular section such that it is at or behind the vertical plane of the aft edge of the radiator then you're compliant.

GA

P.S., Mr Original Asker, please note that nothing decided on this board even begins to imply what answers you'd get during a protest and/or appeal. This is the Internet and these opinions are worth exactly what that implies...