"The Confines of the Engine Compartment"

We tried one to baseline from a HP and an air-intake temp perspective. We built a better one by V.3 and V.4. (by my definition - torque curve)

As to the plastic over in front of the radiator, I kept mine. It actually keeps better air into the radiator. Back in the day, the 1.6 SM guys were adding the 1.8 piece IIRC to improve cooling. It might be specifically allowed in SM.
 
I don't mean to complicate the issue, but it reminds me of the stock airbox/ramair setup of the S5 RX7.
It seems to me that if none of the fast RX7 guys utilize these stock parts, it probably isn't worthwhile.
What I do know is that we toyed with it, and we determined that its volume flow restriction would likely
outweigh any possible (and doubtful) pressurized advantage

View attachment 3731


Go back and look again, you missed something.
 
The rules are pretty clear about no 'ram-air' and this would put the air intake into an area of higher pressure than it would normally have in it's stock location. You have to remove the plastic trim for it to work.

Two strikes, you're out.
 
Agreed. No plastic piece and no air intake there? Cool (IMO). No plastic piece AND intake there? Too far.

Now I need to go find one of those plastic pieces. Agree with Andy on using it to keep temps down.
 
As to the plastic over in front of the radiator, I kept mine. It actually keeps better air into the radiator. Back in the day, the 1.6 SM guys were adding the 1.8 piece IIRC to improve cooling. It might be specifically allowed in SM.

It is allowed for the 1.6 in both SM and SSM, and makes a big difference in cooling. I've run my car back to back with and without and the differences on an 80 degree day were immediate.
 
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


Just to debate the definition of the Engine Bay/Compartment .

Where would the radiator be located, or described as being located, if it's not the considered the engine compartment ? I would think anywhere under the hood, and aft of the grill , would be considered as engine bay . Plus, I believe in the definition that Greg supplied, makes no reference to for or aft of the radiator being a boundary for the engine compartment.

-John
 
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Just to debate the definition of the Engine Bay/Compartment .

Where would the radiator be located, or described as being located, if it's not the considered the engine compartment ? I would think anywhere under the hood, and aft of the grill , would be considered as engine bay . Plus, I believe in the definition that Greg supplied, makes no reference to for or aft of the radiator being a boundary for the engine compartment.

-John

cool, so my whole car is engine compartment?
<--- drives an MR2
 
yes ...yes it is...:D HA I totally forgot about the mid/rear engine cars...!

You must now drive backwards....
 
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It is allowed for the 1.6 in both SM and SSM, and makes a big difference in cooling. I've run my car back to back with and without and the differences on an 80 degree day were immediate.

Agreed, these do matter for cooling. Dave, look around online, some of the Miata aftermarket places have the factory pieces availabe (gomiata I think?). I just put an NRG aluminum panel on my SU car becauase bling matters... (and it was the same price as the factory piece, and I don't have rules to live by)
 
...definition that Greg supplied, makes no reference to for or aft of the radiator being a boundary for the engine compartment.

-John

Damned good thing, particularly if you're talking about cars like the Fiero or the soon-to-be-classified-I'm-sure Austin America. :)
 
Hi guys,

Just responding to the question of "Ram Air", as it was discussed in the forum. Back in the day, I was protested for this item in ITB. I then referred to the GCR Technical Glossary, where "Ram Air" is defined (fancy that). In 2011, the definition was: "A type of induction system in which the incoming air is obtained from an extension into the airstream outside the bodywork." Bold is mine.

No one has mentioned a reference to the glossary, so I thought I'd bring it up. If this definition still exists, then the discussion could take another turn?

Good racing,

Bill:024:

Good racing.
 
No real impact I think Bill.

THe issue here is what is "inside the engine compartment" since our rules allow the pickup of air there, or in the stock location.

To me, the radiator has to be the forward definition of the engine compartment. Otherwise, you could use the void between the grill and the radiator on pretty much any car to make an effective and never intended cold air intake.

Based on that, he Jackson intake is not legal as it extends past the rear of the radiator. Cut it off there and probably legal.
 
I agree with you, with the following:

...radiator has to be the forward definition of the engine compartment. Otherwise, you could use the void between the grill and the radiator on pretty much any car to make an effective and never intended cold air intake.
This is supported philosophically, in that the regs do not allow you to make a shorty radiator and leave a hole next to it for air intake. It would be nice, howver, for that to be explicitly clarified in the regs (easy to supplement the "engine compartment" definition within the ITCS.)

Based on that, he Jackson intake is not legal as it extends past the rear of the radiator. Cut it off there and probably legal.

I agree that the intake portion of it should be behind the plane of the radiator. However, there is no restriction to the mounting portion of it needing to be behind that, as long as air is not taken in from there.

GA
 
1987-audi-4000q-5.jpg

Audi 4000 5+5, just for giggles...

I miss that car.

K

EDIT - Whoops. Thats a 4000Q but the radiator layout is the same; ditto for the ITB Coupe.
 
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Agree.

I agree with you, with the following:


This is supported philosophically, in that the regs do not allow you to make a shorty radiator and leave a hole next to it for air intake. It would be nice, howver, for that to be explicitly clarified in the regs (easy to supplement the "engine compartment" definition within the ITCS.)



I agree that the intake portion of it should be behind the plane of the radiator. However, there is no restriction to the mounting portion of it needing to be behind that, as long as air is not taken in from there.

GA
 
I dislike the radiator being considered a standard part of the outline of the engine compartments due to mid engined cars and oddballs like the 5cyl audis, not to mention 1/2 width radiators found on many hondas and a few other cars.

in the case of the miata - yeah, a fine, common sensical boundary, but I think we should be clear with ourselves that it is not a valid definition in MANY cases.
 
I dislike the radiator being considered a standard part of the outline of the engine compartments due to mid engined cars and oddballs like the 5cyl audis, not to mention 1/2 width radiators found on many hondas and a few other cars.

in the case of the miata - yeah, a fine, common sensical boundary, but I think we should be clear with ourselves that it is not a valid definition in MANY cases.

This is a pretty easy "know it when you see it" thing though. Something like "within the confines of the engine compartment, which is typically bounded by the radiator (front), hood (top), inner fenders (sides) and subframe or other engine mounting points (lower)" -- something like that.
 
definition comes from the technical glossary in the GCR and we just use the term and the allowances for intake ducting in the ITCS. I doubt they will rewrite the definition to suit tin tops because wings and things. better just to, as you say, know it when you see it.
 
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