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int2str

E46 splitter rule clarification

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int2str

Greg,

 

I saw your posts on the FRS splitter, but would like some further qualification for the E46 M3:

 

On the E46 M3, the bumper has 4 "problems":

1. It is contoured with recessed (compared to the center) protrusions (compared to the overall curve of the bumper) on each side

2. It is curved at the bottom (not straight / 90deg angled)

3. There is a gap under the center

4. It is recessed from the actual "bumper" part of the bumper

 

So if the 4" rule is not measured via a plumb line from the bumper, how will it be measured?

 

Example picture (not mine):

APR-CW-544603.jpg

 

If you slide a ruler, it will slide under the center and it will slide back further under the sides by the fog lights.

So how does one measure this to be legal?

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int2str

Also for reference this is the Bimmerworld splitter:

e46_m3_gts3gts4_racecar_for_sale-1435438756-975-e.jpg

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int2str

In the other thread you posted:

 

...Tape measure from the edge of the splitter to the intersection with the vehicle.

The problem here is that depending on the tape measure it can slide under parts of the bumper on the E46. This makes this measurement completely arbitrary. Plumb line would be easy and consistent.

 

Can we have the rules clarified and amended here?

 

Here's what I can find in the rules:

 

7.3.1 1)

Front wing/spoiler/foil/splitter may not protrude more than 12

inches in front of the outermost edge of the front bodywork/fascia, and may not be

higher than the lowest part of the vehicle’s hood.

This clear and would support the "plumb line" theory.

 

7.3.2 D 2) C

Single flat, horizontal front splitter that protrudes no greater than 4” from the vehicle.

This is not clear and not consistent to the "non-production" rule.

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PSIxGEO

Run a few of these for various classes..looks as though they'd jut out too far in this case

 

front-of-splitter-with-braces1.jpg

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int2str

That's a nice splitter.

Also further shows the problem with the "from vehicle" wording...

Where do you measure from now?

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int2str

Also, is this Bimmerworld riser legal?

 

E46_Carbon_Undertray_Kit_WM.jpg

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427R

Here's what I can find in the rules:

 

7.3.1 1)

Front wing/spoiler/foil/splitter may not protrude more than 12

inches in front of the outermost edge of the front bodywork/fascia, and may not be

higher than the lowest part of the vehicle’s hood.

Regulations affecting bumper design in the late 1970s saw the increasing use of soft plastic materials on the front and rear of vehicles. Fascia was adopted then as the term to describe these soft areas, but is now increasingly used as a general term for a car's set of front-end components: grille, headlamps, front bumper, and other details. So, wouldn't the 12" be measured from the outer most part of the front bumper?

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Greg G.
Greg,

 

I saw your posts on the FRS splitter, but would like some further qualification for the E46 M3:

 

On the E46 M3, the bumper has 4 "problems":

1. It is contoured with recessed (compared to the center) protrusions (compared to the overall curve of the bumper) on each side

2. It is curved at the bottom (not straight / 90deg angled)

3. There is a gap under the center

4. It is recessed from the actual "bumper" part of the bumper

 

So if the 4" rule is not measured via a plumb line from the bumper, how will it be measured?

 

Example picture (not mine):

APR-CW-544603.jpg

 

If you slide a ruler, it will slide under the center and it will slide back further under the sides by the fog lights.

So how does one measure this to be legal?

 

How about take the ruler, and put it on edge (and if that isn't tall enough, assume the 2" height of a T square). The 4" would be measured from OEM fascia, closest to where the splitter protrudes from underneath it. We would not use a plumb bob from the top part of the bumper that overhangs the lower part of the fascia. It doesn't matter if the shape is not straight or has protrusions--4" maximum from any location (which may mean that if you want a smooth curve on the splitter that some points will only be 2" from the fascia protrusions).

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Greg G.
Run a few of these for various classes..looks as though they'd jut out too far in this case

 

front-of-splitter-with-braces1.jpg

This piece does seem to follow the air dam rule, and if that center portion was 4" or less from the air dam, then it would be legal.

b)"Vertical front air dam (5º tolerance) that follows the outermost edge of the front and

side bodywork/fascia."

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Greg G.
Also, is this Bimmerworld riser legal?

 

E46_Carbon_Undertray_Kit_WM.jpg

This piece does not appear to be compliant with the air dam rule:

b) "Vertical front air dam (5º tolerance) that follows the outermost edge of the front and

side bodywork/fascia."

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Greg G.

Here's what I can find in the rules:

 

7.3.1 1)

Front wing/spoiler/foil/splitter may not protrude more than 12

inches in front of the outermost edge of the front bodywork/fascia, and may not be

higher than the lowest part of the vehicle’s hood.

Regulations affecting bumper design in the late 1970s saw the increasing use of soft plastic materials on the front and rear of vehicles. Fascia was adopted then as the term to describe these soft areas, but is now increasingly used as a general term for a car's set of front-end components: grille, headlamps, front bumper, and other details. So, wouldn't the 12" be measured from the outer most part of the front bumper?

The 12" is not his concern, it is the 4" for ST4/TT4. The 12" rule was to get rid of the crazy front wings we were starting to see more frequently.

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