robits325is
New member
The last E-36 328 Coupes produced in 1999 had the M3 moldings and Luxury Bumpers (M3 bumpers without the black lip spoiler) These parts were on cars that had the Sport Package.
So when is a wing legal in IT?
- Thread starter Doc Bro
- Start date
Like this. 99 328 is sport package;
or this;
http://cgi.ebay.com/ebaymotors/BMW-...oryZ6007QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
So the M3 bumpers and side trim can be run on a 96 328is using the same spec line arguements (as the 99 328 is sport package) already mentioned above....so there's really no need to look into the M technic package.
Si?
ps Thanks Rob
R
Andy Bettencourt
Super Moderator
Yup. Although the M3 luxury front bumper is different than the regular M3 unit.
All you are doing is updating and backdating front bumper assemblies for a car with multiple years on it's spec line. No VIN rule application here.
To apply the VIN rule removal to your situation: Like Dave Maynard is doing - taking a 325 and turing it into a 328. Before the recinded rule - illegal. In 2009, legal.
But again, since there was no 328 M-technic in the US, you have nothing to update - backdate to in order to get THAT SPECIFIC front bumper.
Ahhhh yes but aren't splitters allowed? Why can't I use the BMW splitter (lip) that came on the M3 bumper?
Devil's advocate mode off
R
Andy Bettencourt
Super Moderator
You can, provided it meets the ITCS rules for splitters. The difference is in the 'mouth' of the grill. Slats for the luxo, honeycomb for the standard IIRC.
...and you can't remove the whatever "splitter" or lip came on the bumper skin, in order to install the one that came on the M3.
I've had dozen or more VW fans tell me I should just use the VR6 lip spoiler, or any of the many aftermarket options, but they all fit only when the stock one is removed. And there's no allowance for that.
K
I've had dozen or more VW fans tell me I should just use the VR6 lip spoiler, or any of the many aftermarket options, but they all fit only when the stock one is removed. And there's no allowance for that.
K
shwah
New member
Yeah - that one caught me out. I'm changing it, but its a bad rule IMO. There is no sense in creating an allowance for 'open front spoiler' (within stated constraints), yet not allowing it to replace any exsiting front spoiler. Looks like an oversight to me that only serves to make it more difficult to execute the allowance.
You guys get my letter on that yet?
Andy Bettencourt
Super Moderator
Yeah - that one caught me out. I'm changing it, but its a bad rule IMO. There is no sense in creating an allowance for 'open front spoiler' (within stated constraints), yet not allowing it to replace any exsiting front spoiler. Looks like an oversight to me that only serves to make it more difficult to execute the allowance.
You guys get my letter on that yet?
Technically, spoilers and splitters aren't free. You are allowed to ADD a spoiler or splitter to what you have. Subtle but important difference. Otherwise some intorturetation would occur about what could be removed, how much, why and when...etc. In this case, I agree that adding or changing any language could cause problems.
You can - and should however - UD/BD to the front bumper assembly that best suits your needs, from your spec line. Those needs could be cooling, aero, style, ease of additional mods, etc.
+1
A repost from a few years ago here (which I re-posted in the Sandbox last week...)
Splitters were never "allowed" in IT; show me where they're explicitly addressed? We had this conversation on this forum a year or so ago, but splitters showing up in I.T. were as a result of the evolution of cars in the 70s and 80s from those with detached metal bumpers to those in the 90s incorporating integral bumper covers. Within the confines of your typical IT-legal car back when the rules were written, splitters were virtually impossible to make (and not thought of; I don't think I saw one on a pro race car until maybe early 90s in WTCC or BTCC?).
Enter the integral bumper cover and now you've scads of horizontal space to mess with behind the vertical nose, coupled to graphic examples in Pro racing to emulate and - voila! - splitters show up in Improved Touring.
...
The air dam/spoiler has historically been viewed as a drag-reduction item, not a downforce-producing (or lift-decreasing) device. We didn't have complex computer flow modeling 25 years ago, all we had was seat-of-the-pants, "hey I'm going 5 miles per hour faster into the bridge at Road Atlanta" type of testing. You'll notice in that article that the affect on drag reduction (mostly from reducing under-body turbulence) far outweighs its affect on downforce, and that is typically supported by the seat-of-the-pants-wind-tunnel testing.
Given its drag reduction value, there had to be limits, and those limits were set (generally speaking) at no lower than the bottom of the wheel (so a flat tire does not cause it to drag), no higher than 4 inches above the center of the hubs (so that you cannot use it to reduce cooling drag), no farther back than the front of the wheel openings (so that you cannot use it to reduce wheel opening drag), and within the outer confines of the body outline (so you can't use it to produce downforce with extended winglets). Of course, think of the cars we had "back then": most of them were blunt front cars with protruding bumpers (think Pinto, Capri, Rabbit, Scirocco, Civic, TR-7, etc). Most of these cars did not have integrated bumpers and if you followed the rules it would be VERY difficult to construct any type of aerodynamic downforce given the horizontal restrictions and protruding bumpers excluded.
Today that's not the case; most cars are shipped with enclosed integrated bumper assemblies and it's perfectly legal to the rules to attach something under that cover. You mount an air dam under the nose of your Z3 and you'll have a good 4 to 6 inches of forward horizontal space to work with before you hit the tip of the nose. That can be a big advantage (especially for FWD cars).
Geo's favorite slogan is "if it says you can, you bloody well can." While there are no allowances to install a splitter, there are insufficient restrictions on the air dam to disallow one. Who's to say that this piece is a "not specifically allowed" aerodynamic device or actually a specifically-allowed air dam part? Absent those restrictions, the "openness" of the air dam rule pretty much allows you to do whatever you want within those physical boundaries.
So, it's not that the SCCA is specifically allowing a splitter and thus frontal downforce; I'm of the opinion that it was not even considered at the time the rule was written simply because "they" could not have foreseen the design of current vehicles... - GA
Enter the integral bumper cover and now you've scads of horizontal space to mess with behind the vertical nose, coupled to graphic examples in Pro racing to emulate and - voila! - splitters show up in Improved Touring.
...
The air dam/spoiler has historically been viewed as a drag-reduction item, not a downforce-producing (or lift-decreasing) device. We didn't have complex computer flow modeling 25 years ago, all we had was seat-of-the-pants, "hey I'm going 5 miles per hour faster into the bridge at Road Atlanta" type of testing. You'll notice in that article that the affect on drag reduction (mostly from reducing under-body turbulence) far outweighs its affect on downforce, and that is typically supported by the seat-of-the-pants-wind-tunnel testing.
Given its drag reduction value, there had to be limits, and those limits were set (generally speaking) at no lower than the bottom of the wheel (so a flat tire does not cause it to drag), no higher than 4 inches above the center of the hubs (so that you cannot use it to reduce cooling drag), no farther back than the front of the wheel openings (so that you cannot use it to reduce wheel opening drag), and within the outer confines of the body outline (so you can't use it to produce downforce with extended winglets). Of course, think of the cars we had "back then": most of them were blunt front cars with protruding bumpers (think Pinto, Capri, Rabbit, Scirocco, Civic, TR-7, etc). Most of these cars did not have integrated bumpers and if you followed the rules it would be VERY difficult to construct any type of aerodynamic downforce given the horizontal restrictions and protruding bumpers excluded.
Today that's not the case; most cars are shipped with enclosed integrated bumper assemblies and it's perfectly legal to the rules to attach something under that cover. You mount an air dam under the nose of your Z3 and you'll have a good 4 to 6 inches of forward horizontal space to work with before you hit the tip of the nose. That can be a big advantage (especially for FWD cars).
Geo's favorite slogan is "if it says you can, you bloody well can." While there are no allowances to install a splitter, there are insufficient restrictions on the air dam to disallow one. Who's to say that this piece is a "not specifically allowed" aerodynamic device or actually a specifically-allowed air dam part? Absent those restrictions, the "openness" of the air dam rule pretty much allows you to do whatever you want within those physical boundaries.
So, it's not that the SCCA is specifically allowing a splitter and thus frontal downforce; I'm of the opinion that it was not even considered at the time the rule was written simply because "they" could not have foreseen the design of current vehicles... - GA
shwah
New member
I understand and agree how the rule is written. I just don't agree that it is a good rule. Please let me know what undesireable result we would have if the rule allowed the 'addition of an air dam, or replacement of original equipment air dam'. The intorturation can't get around the limitations on creating new openings, etc. AND any car that has no air dam from the factory can come up with thouse intortuations right now. What is allowed in an airdam is clearly defined, and those words have stood the test of time. Allowing addition or replacement won't change that, it will just change the fact that folks are installing new airdams, and designing them so that they can be mounted in front of, and render completely functionless, any oem air dam.
For update/backdate - it's funny. For one version of a front bumper on my car, it is a separate bumper with a fascia, which was delivered at times with no air dam at all. The other has an integrated bumper design like the Golf 3, which always includes an air dam. In that case we have to do exactly what Kirk is doing - run the little stock one, or design an additional one, but don't do something sensible and mount it to the stock mounting points (like I did), design it to mount in front of that to the bumpe surface.
It's not a valid argument, but this is a dumb rule IMO.
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Not true. Being able to remove parts that would otherwise exist behind an added-on spoiler would SIGNIFICANTLY enhance the ability for ducting air to brakes, coolers, radiators, etc.
http://www.improvedtouring.com/forums/showpost.php?p=199413&postcount=44
In addition, being able to remove those parts will SIGNIFICANTLY improve the ability to make spoilers/splitters/airdams, etc. I can assure you that were I able to remove the front valence on the Integra I'd have a BTCC-like front airdam/splitter on that thing, toute-suite...
This isn't a slippery slope, it's a cliff.
GA
completely agree that the rules as written do not allow for the removal of any of the factory front aero bits (lip spoilers, etc) as covered by Greg A and Kurt.
an observation:
ITS RX-7s often use the GTU wing and some version of a splitter, many of which bolt or otherwise attach to the bottom of the factory bumper cover. didn't the GTU model also had a lip spoiler attached to the bottom of the front bumper? I cannot tell if pre-1989/non GTU models had such an appendage.
should an RX-7 running the GTU rear spoiler be required to have the GTU front spoiler and an air dam that does not bolt on in its place(replace it)? or are the GTU aero parts independently allowed? from my observations, this ruling could make a lot of those ITS cars illegal. that's a pretty well understood and thus strongly self policing group - so I'm probably missing something but if I'm not...
thoughts?
an observation:
ITS RX-7s often use the GTU wing and some version of a splitter, many of which bolt or otherwise attach to the bottom of the factory bumper cover. didn't the GTU model also had a lip spoiler attached to the bottom of the front bumper? I cannot tell if pre-1989/non GTU models had such an appendage.
should an RX-7 running the GTU rear spoiler be required to have the GTU front spoiler and an air dam that does not bolt on in its place(replace it)? or are the GTU aero parts independently allowed? from my observations, this ruling could make a lot of those ITS cars illegal. that's a pretty well understood and thus strongly self policing group - so I'm probably missing something but if I'm not...
thoughts?
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Andy Bettencourt
Super Moderator
Just so you know, the rear spoiler you see on most ITS RX-7's came on the GXL as well. The actual lower spoiler came on the Turbo and the GTUs and was VERY rare. Check this link to the S5 model line up.
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well ok then. glad I'm wrong.
for clarification, though - the allowed factory aero parts (any car) can be UD/BD as a group only, correct? i.e. a specific factory wing and side skirt (rocker trim) combo package would allow the use of the entire package or just the wing only (skirts removed per ITCS D.8.k) but not the skirts alone. correct?
shwah
New member
But you are allowed to add holes/ducts to the oem parts to facilitate brake cooling anyhow. What new gain is being had here?
You can build a BTTC front air dam now too, you just have to mount it on top of the oem stuff.
Yes it will get easier to build the parts. No it will not enable some additional performance enhancement.
Do you guys seriously think that the logic in allowing a non-stock air dam, but requiring the retention of a now non functionaly stock air dam is sound, and somehow acting as a performance limitation?
edit - looking at the linked post - maybe another poorly written rule. The intent is clearly (to me) to allow brake ducting up to 3" diameter. I guess another letter should be written. Honestly - in my case it makes no sense to go to a larger duct, as space to get the duct to the brakes is limited, and I don't seem to need anything more for my brake package, so I never gave that topic as much of a critical read as you have. I am sure that there are other cases - like the Triumph - that desperately need as much brake cooling as they can get, so I understand the potential performance ramification.
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Here's where we get into yet another historical original intent versus current practice. The rule states, specifically,
Any updated/backdated components shall be substituted as a complete assembly (engine long block, transmission/transaxle, induction system, differential/axle housing). No interchange of parts between assemblies is permitted, and all parts of an assembly shall be as originally produced for that assembly (such parts may, however, be coated, painted or plated). Additionally, it is not permitted to “create” a model or type of car by updating or backdating assemblies.
I'm not confident the rules were originally intended to apply to anything but mechanical assemblies (as illustrated by the examples offered). Regardless of what you do, however, it's important to note the "not permitted to “create” a model" limitation.
I see the UD/BD rules as nothing more than an early variant of the new no-VIN rule. I use as a basis for deciding legality the example of bringing in somene intimately familiar with the make/model: aside from the VIN, they should not be able to determine that the car and its assemblies did not come that way from the factory. - GA
If you cut into factory parts you're limited to 3" diameter.
But with the factory stuff there I am limited in horizontal placement and extension. With the OEM stuff gone I can set the air dam back a foot or so, make a very large and effective horizontal splitter, add upturns for downforce well within the vertical outline of the body, and clearly and directly divert large volumes of high pressure air to the brakes (a distinct advantage on this car).
Yes.
shwah
New member
Agreed. Another area that is not adequately defined. My opinion is that the intent of the rules were to allow max 3" brake ducting. In which case this becomes a non-issue. Currently it is not a very sensible section of the rule set.
Of couse any splitter element that has a coresponding surface facing the ground rather than the sky has limited effectiveness anyhow. Any increased pressure realized will work on both surfaces, though more effectively on the horizontal surface. Not to mention that you can still do this with the stock peice in place, make the allowed air dam such that it has a vertical plane lower than, and further back than the stock item, creating a larger horizontal plane on the splitter.
Sorry I forgot which car 'this car' is, but would like to see some data showing how much more air 'large volumes' afforded by not having to keep the oem air dam are, vs the alternative - due to pressure increases. Heck a measurement of the pressure increase itself would be telling in how little impact this will actually have.
All of the above considers that we 'fix' the brake cooling duct rule to specify 3" diameter in all cases.
We disagree. Especially when considering how many cars are not impacted by this odd restriction. We should certainly see some, or at least one, example of the advantages you cite being developed at some point over the past 3 decades, yet I don't believe we have.
shwah
New member
I guess a good analogy for the way I see this rule is, allowing the use of any air cleaner, but requiring that you also retain and route air through any stock air cleaner, or allowing the use of any radiator, but requiring it be mounted in front of or behind any existing radiator. Sure there may be a performance advantage of the 'real' rules over these alternateives, but the rules also make sense.
Not to be confused with allowing use of other air/fuel measurement/metering vis a vi aftermarket ecu, MAP sensor, and other allowances, but requiring air to flow through the stock, possibly no longer utilized air measurement device - because potential flow restrictions of the stock device are germane to the power potential of the car as classed. I am not aware of any input to the classification process based on aero or downforce efficiency - or really even brakes/brake cooling. (although maybe that is why the Scirocco was classified heavier than its chassis mates in all classifications back in the olden days - but that is another topic for another time)
Not to be confused with allowing use of other air/fuel measurement/metering vis a vi aftermarket ecu, MAP sensor, and other allowances, but requiring air to flow through the stock, possibly no longer utilized air measurement device - because potential flow restrictions of the stock device are germane to the power potential of the car as classed. I am not aware of any input to the classification process based on aero or downforce efficiency - or really even brakes/brake cooling. (although maybe that is why the Scirocco was classified heavier than its chassis mates in all classifications back in the olden days - but that is another topic for another time)
BTCC 2006 (note: BTCC also has a "vertical outline" rule...):
BTCC, 2007:
BTCC 2009 (pre-season testing):
