Quick IT questions

[woodc]

I am converting my 96 Miata from a CSP time trials car to an ITA Miata and have a couple of quick questions :)

After reading thru the IT section of the GCR more than once I have a couple of things I am fuzzy about....

1) I don't see where I can remove the mat on the firewall behind the dash yet each picture I see of a car stripped down for a cage install that sucker is gone. Do you just remove that for painting and cage installation then put it back before the dash goes in?

2) A Pillar trim and the trim around the windshield frame....may these be removed under "cage fitment"?

3) Door sills...same question?

4) The AC box can be replaced with an AC delete duct from Mazdaspeed no questions asked right?

Thanks all!

[Greg Amy]

We shall teach the autocrosser how to become a true GCR rules nerd...;)


1) I don't see where I can remove the mat on the firewall behind the dash...
9.1.3.D.9.f: "Carpets, center consoles, floor mats, headliners, sun roof liner and frame, dome lights, grab handles, and their insulating, attaching or operating mechanisms may be removed."


A Pillar trim and the trim around the windshield frame....may these be removed under "cage fitment"?Same section as above: "All other interior trim panels, except the dashboard, may be removed."


Door sills...same question?Door sill trim? Same as above.


The AC box can be replaced with an AC delete duct from Mazdaspeed no questions asked right?Yes. Any optional equipment can be removed and replaced with the non-option parts.

[Knestis]

...assuming that non-AC cars were ever delivered in the US. The definition of "optional" can be kind of loose for some among us.

K

[woodc]

Thanks all!

And Greg Amy....time trials....not autox....autocross was the life before last :D

[JoshS]

I've gotta disagree with Greg on the firewall insulator for a strict reading of the rules, and the reading I used when I was building my car.

Simplifying, the rule states that A and B can be removed, as can their insulating mechanisms. There is no allowance to remove insulating material that doesn't insulate A or B. The dash is not listed in the list of things that can be removed, so why do you think it's insulator can be removed?

[JeffYoung]

Josh, there is more to the rule than what Greg cites:

Carpets, center consoles, floor mats, headliners, sun roof liner and frame, dome lights, grab handles, and their insulating, attaching or operating mechanisms may be removed. Sound deadening (melt sheets) and undercoating may be removed. Door interior trim panels may be replaced with 0.060" - 0.065" aluminum securely attached to the door. All other interior trim panels, except the dashboard, may be removed. Other than to provide for the installation of required safety equipment or other authorized modifications, no other driver/passenger compartment alterations or gutting are permitted.

That's a pretty recent change. I think it was enacted due to that fact that we were all removing undercoating as "insulating material" and the rule may not have been that explicit.

I mean, ALL IT car builders should have to go through the forced ritual of undercoating removal...without it, you rule aren't an IT guy.....

[JoshS]

Josh, there is more to the rule than what Greg cites:

Sound deadening (melt sheets) and undercoating may be removed. Door interior trim panels may be replaced with 0.060" - 0.065" aluminum securely attached to the door. All other interior trim panels, except the dashboard, may be removed. Other than to provide for the installation of required safety equipment or other authorized modifications, no other driver/passenger compartment alterations or gutting are permitted.

That's a pretty recent change. I think it was enacted due to that fact that we were all removing undercoating as "insulating material" and the rule may not have been that explicit.

I mean, ALL IT car builders should have to go through the forced ritual of undercoating removal...without it, you rule aren't an IT guy.....


I agree Jeff, but still nothing in that rule allows for dash insulating material to be removed (unless that's made of melt sheets) -- in my car, it is a huge thick fiberglass (or something) pad.

[JeffYoung]

I think the parenthetical is unfortunate, because the general "gist" of the rule has always been (or at least every car build I've known has interepreted it this way) that all sound deadening material of any kind (not just melt sheets) comes out.

[RacerBill]

Pardon my ignorance, but what is a 'melt sheet'?

[lawtonglenn]

http://geoweb.princeton.edu/people/keller/fig17.jpg

[RacerBill]

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Hope you don't have one of these in your car!

Think you would need something more than a SA2005 and an Isaac!

[Xian]

Pardon my ignorance, but what is a 'melt sheet'?

I believe it's the tar like sheet(s) of sound deadening on the floor in many cars.

[GTIspirit]

4) The AC box can be replaced with an AC delete duct from Mazdaspeed no questions asked right?





Yes. Any optional equipment can be removed and replaced with the non-option parts.

What about this clause regarding the A/C?


e. Air conditioning systems may be removed in whole or in part.
Sounds to me like anything A/C related can be removed.

And as far as the melt pads, what about underhood melt pads, i.e. melt pads in the engine compartment not the passenger compartment? May they also be removed?

[woodc]

A couple more quick questions:

The GCR states "a maximum of two gussets per rollcage joint are allowed". What is the definition of a rollcage joint? If 3 tubes come together in one spot how many joints is that?

[woodc]

Why does the forum keep thinking my post has email or web addresses thus not letting me post (under 4 posts apparently)?

[woodc]

This is the post it kept gagging on....I guess the miatacage dot com part was the issue:

The GCR states in 9.4.2 J "In order to provide a secure seat back support a section of tubing equal to the rollbar shall be installed horizontally from the main hood upright to the diagonal brace. This tube shall be no higher than shoulder height."

In cages such as the miatacage dot com that only have one horizontal bar what is the optimal/legal height to install it so it can satisfy the seat back support *and* harness bar rules? The bar needs to be below shoulder height for the seat but how far below...since lower = more chance of compression injuries :shrug: I don't want a cage that a taller person than me cannot be safe in either....

Also...if you run an FIA seat and thus do not use the cage for any seat bracing does this rule even apply?

[lateapex911]

What about this clause regarding the A/C?

Sounds to me like anything A/C related can be removed.



This one is controversial. Some say that in cars equipped with central boxes that route AC AND heat, the entire box may go, leaving the heater core hanging, essentially. Others look at that rule and think it refers to items that are exclusive to the AC system.

I think the first position is really stretching it, and the second is appropriate.