Prelims are out:
5/07/12- Preliminary Minutes
5/07/12- Preliminary Tech Bulletin
Printable View
Prelims are out:
5/07/12- Preliminary Minutes
5/07/12- Preliminary Tech Bulletin
ITA
1. #7633 (Christopher Childs) Increase weight of 1.8 ITA Miata
In ITA, Mazda MX-5 / Miata includes R (94-97), change the weight as follows: 2460
Neal Harrison is building one. I think that car has potential, Chris Newberry's was FAST.
I don't think the Miata change will generate any discussion. Nope. None. I'm sure of that.
Mostly started due to the CRB's disagreement with the use of the lower stock hp number for the car, and the inconsistency in doing that with the Miata versus all other cars in the ITCS.
I initially did not want to change this since it has been debated ad nauseum, but ultimately voted yes (I think the vote was unaminous).
There was no pressure from the CRB to do one thing or another, but they did raise the issue with us.
Yessir. Being as how my car only needs to rev to 5200 RPM I propose 5200.
Jeebus, are we really going to have to read page after page of ITA Miata minutia (no offense to quoted poster)? The situation has been debated for years. Bridge, water under it, and all that. Other cars get processed at the highest rated hp, this one should be no different.
Sorry for asking dumb questions, but what is the underlying reason for not allowing cars to run in different IT classes at different weights? I understand that there are potential problems that the driver would have to deal with in terms of wheel size between classes (ITA to ITB etc). But as long as the car is compliant, why does this keep getting shot down? It seems that if you wanted to run your ITA miata in ITS at a lower weight, go for it.
Is there some real reason for this or is it another washer bottle? I'm hoping somone can provide the cliff notes.
As someone who argued against double-listing, it's a solution to a non-problem, with lots of minor downsides that add up to make it more trouble than it's worth.
** Our classes are confusing enough as it is, without people having to figure out if that's an ITB Golf II or an ITC Golf II
** If (when) something like the ITS Nissan 240 weight changes, it would have to propagate to two classes rather than one. A change can't always be accommodated within the "bucket" established for a class (e.g., if it would make it too heavy for a given rollcage tubing size, or be impossibly low).
** We already have outlier issues, in terms of light cars or big engines, and dual listing will create more of them - cars already outside (or at minimum, right on) the limits of the class, made super-light or extra heavy to fit.
** At the end of the day, it doesn't give anyone anything they don't already have...
K
So this is going to be a long post, and I ask everyone to read it and REALLY try and understand it. I also challenge any ITAC or CRB member to bring forth any reasonable arguments. Anyone who agrees with the philosophy of the change (like Greg), I would like to hear their arguments as well. Maybe I am missing something. It should always be the job of the committees to put in the work and class things as 'right' as they can.
First off, this classification is NOT inconsistent with the way other cars are classed because it is DIFFERENT. Read that again. It's different. I am going to lay out some generic scenarios for you in an effort to try and reduce the Miata bias.
Take car A. Car A had a body style run from 1990-1993. From 1990-1992, it had 130hp. In 1993, they tweaked the intake manifold and the cams and the new rating was 140hp. Now, if the 1990-1992 car was classed first, it would be classed based on the 130hp number. You would then have a choice as the CRB. Add another spec line because the cars are different, or combine them at the higher HP because the items that make the extra 10hp are not legal to change in the lower HP version - and then allow the UD-BD so that the lower HP car can actually make a real base number. Following me? It's a mechanical change that CAN be done to can extra HP in IT trim.
Now, take car B. Car B had the same body style run and the same HP change. But the extra 10hp came from a tuned set of headers and a low restriction exhaust. Are we saying that the new stock HP is the way to class this car. HELL NO. Why? Because those mods are already taken into account in the IT weight calculation. Follow this logic:
Lets say for arguments sake that there are 4 things that contribute to a cars 25% potential increase in IT trim (just using round numbers to make it easy. We know every car responds differently). Air intake 5%, exhaust 10%, B&B - port and compression 5%, and ECU 5%. There is your 25%. If a car gets a bump in stock HP SOLELY because of one of these, you have not increased it's potential HP in IT trim. You can not argue this. In the above example, all you did was erode the 10% increase in an optimized exhaust, you did not add 10hp to the baseline number. So you COULD use the higher number to class it but you would then have to reduce the potential % gain the car will get - netting the same original weight.
Take the 2 versions of the 2nd gen RX-7. One had 146hp and one had 160hp. That 14hp difference was made up of basically 3 key items. A MAF instead of an AFM, different intake manifold design and higher compression rotors. All three things that you can not change in IT. These cars COULD be on different spec lines with TOTALLY different HP in IT trim.
NOT true with car B above. Those cars have exactly the same HP potential in IT trim. There is nothing 'mechanical' that you can change that would bump the base hp of the early car up to that of the later car. When I say this, we need to be clear. This 'something' has to be a feature that is not otherwise allowed to be changed in IT. In other words, something you could UD-BD to that would bump the HP.
Another example. Let's say Nissan had a 240SX 'Type S' at 140hp and a 240SX 'Type R' at 160hp. All they changed was the exhaust and the ECU. The Type S is already classed. Then the Type R comes in and all it has is optimized equipment under the IT rules. There is NOTHING different in the two cars in built IT trim. You DON'T bring the bottom car up to the top car and THEN add the 25%, because you would be forcing the car to actually gain about 43% in order to make it's process power.
Even more simply (because this is very hard to explain), Car A has 130hp. Honda does a Type R version with a factory optimized IT package. It now has a rated 162hp. You wouldn't take the 162hp version and class it at 25% additional power because the Type R version has used up 100% of the IT gain and there is ZERO more to get.
So to bring it back to the Miata, this is exactly what happened. The 128hp car was classed, then later, the 133hp car was requested. When you look at the differences, the cars are identical except for an ECU tweak. Since this is an allowed mod in IT, it renders the improvement 100% moot when discussing potential in IT trim. And THAT folks is how cars are classed at the core level. Potential hp in IT trim. The change in ECU adds nothing to the base HP as it affects HP in IT trim. If it were a larger TB or something you could not legally change, then yes 100%. So if you wanted to use the 133hp number for 'consistency', go ahead, but you must compensate with a lower potential gain in IT trim, say using 20%...which gets you to withing 5lbs of where the car is classed now (figuring 2370 because of the old slush 10lbs). But this is silly because it would be very hard to pinpoint the % of one modification under the rules...so you simply use the standard 25% on the correct number.
One thing that should concern us all is that this line of thinking has been debated and voted on at the ITAC level. It is codified in the Ops manual and had seemingly been accepted by the CRB for over a year now. So effectively, the CRB has decided that (which is their right I suppose) that the Ops manual is out the window for this car but yet it holds firm on it even when it's wrong (see DW adder in ITR). Sweet. We should all be happy with the inconsistency.
So there is data that shows the Miata makes more than 25% but less than 30%. Ok, fine. A weight change based in THIS line of thinking is actually the unprecedented kind. 25% to 27% on a motor like this is 2.5 crank HP...or 2whp. Anyone who wants to adjust the weight of a car based on 2whp is nuts. Let's be real here.
This isn't a Miata issue, it's an issue about whats the right way to class a car. To the Miata, I am not aware of any dyno sheets that show the Miata to be capable of 25% on top of the 133hp number that already includes a % for ECU (as described above). Interestingly, 128hp @ 30% and 133hp at 25% are almost identical. So the Miata is getting classed at a number not yet represented in any dyno data and at a level that doesn't make sense.
It's obvious the Miata is a lightning rod but we need to be worried about classing decisions that make sense because we have put forth effort and thought instead of seeing what we think we see.
If you have a real need to add weight to the Miata, then do it in a way that is consistent and makes potential sense. It's probably more than the sum of it's parts...so add in another variable that not many cars have - like a rear DW adder. I proposed it, it was shot down. This would add an additional 50lbs to the Miata while legitimately trying to quantify a real difference in it's contemporaries - EXACTLY what an adder is suppose to do.
I'm trying to think of examples Jeff, where there has been a car that was classed at X power, then a later version was classified with X +5hp (or 10, 15, etc) that was the result of a change of an IT allowed mod.
I'm coming up empty. Clearly the CRB and the ITAC have examples, or there would be no claim of inconsistency. Can you cite them for us?
OK. What the heck is "required wiring rendered redundant by allowed modifications (i.e. engine management harness)"?
Can that be translated into English. Is this the same body that seems to think that you can physically change the wires and where they go to and from in the engine wiring harness, to enable sequential fuel injection, whether wiring supporting such was there from the factory or not?
The request was simple. If the wires DO NOT DO ANYTHING ON A LEGAL IT CAR let us take them out. Why not leave it simple?
Just build your car like that and call it a day. Motor legal, suspension legal, drive line legal, race over min weight - go have fun.
I have no idea why the wording can't be simplified to something that does what every IT-builder ends up doing. If I were IT Czar there wouldn't be a rule on wiring beyond something like "Cars need wires, use some." All that said, I probably have more wires than the average IT car since mine still wears a tag and will continue to wear a tag.
But, make sure you're using the rules to the full advantage, examples:
*AC systems can be removed in part or entirely" - In a Mustang the entire assembly of heater core, evaporator, etc. is called "Air Conditioning". Wires make that make any of that work are part of the AC, therefore, they are part of the system and can be removed.
*Mustangs without power windows, theft systems, ABS, aux lights, and other optional equipment exist therefore I can remove all the wiring on my car because there are examples that don't have those items.
As you know pulling apart the harness is a major pain in the butt. But it is worth it. We got about 11 or 12 lbs out of optional crap on the first pass. There is 1.5 to 2 lbs I left in because I was afraid to pull due to the safety/theft interlock system.
to avoid unforeseen issues. remove wiring to items you are allowed to remove, effectively allowing you to remove that entire system from the car. you got what you wanted.
but with allowed ECU and related engine wiring harnesses, as well as the existing open rules for wiring of fans, switches, gauges, and the like, we wanted to be sure that the minimal harness being used (you can debate the legality of that specific harness separately) doesn't result in the full stock harness being removed. the last thing we want to see is a squirt on a harness and a small loom for the datalogger and driver controls, with 6 or 7 wires from the stock chassis harness sticking around to connect to the head and tail lights. it's still IT.
V8 F-Bodies are classified using the higher hp number even though the increase was due to an exhaust change. :/
<warning: This is all about ME>
RE: Miata weight........... We hashed this out years ago. Lots of bitterness, anger, name calling (and I'm not being dramatic here). I admit, I was one of the early complainers........... so after years and years of battling Miata's in ITA and getting my ass kicked, I finally break down and buy a Miata. And fucking two months later weight might be added????? You.....have ........got......to.....be.....shittin'..........m e..............
V8's are an anomaly. The CRB at the time was deathly afraid of them, requiring 30% on top number no matter what and this was before the policy was written. Any 'extra' arguing on the V8's could have lead to their non-inclusion. I, for one, hope that the ITR V8's get cleaned up.
What cars are you talking specifically about Chris?
Oh man. THIS is going to be a good thread, I can just feel it.
What Andy said.
This is, at the end of the day, a "someone just thinks it needs more weight because they saw a fast one" adjustment. It's not consistent with past practice or the Process as applied and codified in the ops manual.
K
That can happen. As far as my experience with Mustangs goes we think all were wired for cruise, but, not all were wired for theft, power windows, keyless, etc.
Remove what you can based on the assembly. You can gut the window and mechanisms when you put in NASCAR bars, so take the wires with it. I'm sure if you go through just about any IT car with a fine tooth comb you'd probably come up with some sort of wiring violation. Everyone tries to be legal but in the end I'm sure you could nitpick something on about every car. That's why "Race cars need wires, use some." would be a nice IT sentiment.
Motor, driveline, suspension, min weight. Have fun.
I understand that, I'm just afraid about what it will take to change an already established number...
The 305 TPI GM's. Some of the HP gain between years was from a dual cat option which eventually became standard. I have documentation and it is available to all online. Writing a letter about this is on my list of things to do...
The ITS V6 Mustang stock hp changed over the course of its run, and I believe the higher number was used.
The ITS RX7, same.
My car, same.
The reason for not going with the lower hp number is justifiable. That puts the ITAC and the CRB in the position of having to figure out whether a manufacturer's stock published hp number change was due ot something that is free under the IT ruleset or not. I know that may be clear on the Miata (well, I don't actually know, but I trust Andy on this point), but I don't think it will be clear at all on other cars and there is NO other car in the ITCS that I am aware of that was classed using the lowest stock hp on the spec line.
So I'm actually in general agreement with the criticism of the use of the lower stock hp number for the ITA Miata. I'm not really in agreement with revisiting this after having beaten it to death a few years back but that is what it is.
More importantly, I think we have more dyno data on the ITA Miata than any other car except the MR2. 5-6 sheets from two of the top builders in the country among others.
So let's say the car makes actual whp in the 135 range, which seems to be the case. Using our known hp formula, which effecitvely eliminates the debate over the low v. high stock hp numbers, we get this:
135/.82 * 14.5 +50=2440, or 20 lbs less than the new weight. In my opinion, that is where the car should be and since that is closer to 2460 (the new weight) than 2380 I voted ok on the adder even though I am very concerned about stability and a growing desire on our part (me included) to go back and dick around with hard fought prevoius decisions.
I also personally do not agree with another "sum of its parts" type adder. Those things will build up like barnacles on the hull of the process and kill it eventually. We are way, way better off with far fewer subjective adders than more.
Note this was not a on track peformance based SWAG. Did on track performance influence the decision to look at the car again? Yes. Did it result in the change? No. The real driver for the change was the use of the low stock hp number.
Chris S. -- I see you still don't get the meaning of "modify." So it goes. In any event, we consider your proposal, spent a fair amount of time debating it, and crafted a rule that gave you what you wanted while at the same time addressing some concern our folks had. That rule is clearly written and says if you the rules allow you to modify/alter a part of the harness, but not remove it as a part of an allowed removal of an attendant part, you keep the original redundant wiring. Chip laid it out well. I would think a "thanks for working on my request in your free time and on weekends" woud be appropriate here, but I know that's not the Internet way.
Howdy,
Here's the thing I don't get as a newbie. IIRC, you're the same guy that told me that the '95-'99 SOHC Neon was known to make such good power that it couldn't be processed at 25% like the standard.
So whatever. You'd think more top folks would be jumping over themselves to get into such an overdog, but... Whatever.
With as popular as the ITA miata is (let alone SM), why in the hell are we talking about stock HP and not "as built for IT" HP? Surely there are plenty of examples around?
To me, this looks like someone recognized what everyone knows... I.e. if you want the best ITA car you buy a miata. And they found an excuse in the process that some folks like to think is wonderful and impartial and all to put a little more weight on it. So... Whatever. Whether you call it a rear DW adder or a process change because of a different stock hp rating or whatever the hell you want to call it, it sure seems like everyone is starting with "the miata is dominant, lets figure out a way to get more weight on it".
Mark
Mark, that is basically where I am at. We have good dyno data on this car, showing 135 at the wheels. Which means in reality they probably make more...
But I digress. At that number, using known hp process in the Ops Manual (which dispenses with the low/high stock hp issue), we get 2440 for this car.
That's what I would have done, and since that was closer to 2460 than 2380, I voted 2440.
Another example, and this one should be near and dear too:
ITA 2nd gen CRX Si. '88-90's were advertised at 105hp. '91's at 108. We all know they make way more than 30%. That would be an interesting one to see the weight math on.
Horrible examples Jeff as defined in my post. Each of them has non-IT changable parts that make up the base HP difference. The later car with the better parts has a real base increase that you can ad the full 25%+ to and get your number. NOT the case with the Miata. It's a non-argument, it's simple math.
Doesn't make it not right and doesn't relieve the ITAC from putting in the work to get things right. See Type R IT option from Honda example. How would you class that car?Quote:
The reason for not going with the lower hp number is justifiable. That puts the ITAC and the CRB in the position of having to figure out whether a manufacturer's stock published hp number change was due ot something that is free under the IT ruleset or not. I know that may be clear on the Miata (well, I don't actually know, but I trust Andy on this point), but I don't think it will be clear at all on other cars and there is NO other car in the ITCS that I am aware of that was classed using the lowest stock hp on the spec line.
So you would rather use dyno data that is in the +/-3whp range to set a weight instead of waiting until development took the car (if ever) to the nearest 5%? Holy shit talk about micro managing. THAT is no consistent with stability.Quote:
More importantly, I think we have more dyno data on the ITA Miata than any other car except the MR2. 5-6 sheets from two of the top builders in the country among others.
So let's say the car makes actual whp in the 135 range, which seems to be the case. Using our known hp formula, which effecitvely eliminates the debate over the low v. high stock hp numbers, we get this:
135/.82 * 14.5 +50=2440, or 20 lbs less than the new weight. In my opinion, that is where the car should be and since that is closer to 2460 (the new weight) than 2380 I voted ok on the adder even though I am very concerned about stability and a growing desire on our part (me included) to go back and dick around with hard fought prevoius decisions.
I also personally do not agree with another "sum of its parts" type adder. Those things will build up like barnacles on the hull of the process and kill it eventually. We are way, way better off with far fewer subjective adders than more.
The CORRECT hp number given how we class cars. You simply don't tack on the full 25% to a car that has a factory mod eating into that gain already. Now the car is classed at a number it has never proven to attain yet you have more dyno sheets on it than anything. Super.Quote:
The real driver for the change was the use of the low stock hp number.
I can see why people would look at this funny at first but this is so simple and DOES require some work and some info but what's right is right. If you (the collective you) don't want to put in the work, then let someone else who does. I hate the 'extra work' argument. Again, sweeping statement, not aimed at any one ITAC member.
Andy, we had a good call about this last night. You make good points. However, they often get lost in a failure to recognize there is another side to things in many cases.
It is NOT easy in every case to determine why stock hp changed. I do not think that is a good position to back us into having to do.
Kirk, what drove this change was the low/high stock hp number. I voted for it because that number came out within 20 hp of what I believe the car should weigh based on the dyno info we have (most I've seen for a car other than the MR2).
And since it was processed 'correctly' it isn't an overdog. See how that works?
So you need to read the post more in depth. The whole point is about HP as built for IT. These two motors have the same potential in IT trim, and you base it on the lower number because the higher number is a direct result of an IT-allowable modification that eats away at the 25% expected gains.Quote:
With as popular as the ITA miata is (let alone SM), why in the hell are we talking about stock HP and not "as built for IT" HP? Surely there are plenty of examples around?
This isn't about the Miata as a competitive car in ITA, it's about getting the way we class cars 'correct'. I don't care about the weight either. I am on record as having proposed an additional adder that would have resulted in +50 for my car. I don't care, I just submit what I think is right for the class. This decision is based on flawed math and results in a classification that is not attainable even though the ITAC has tons of dyno info. It's mind boggling.Quote:
To me, this looks like someone recognized what everyone knows... I.e. if you want the best ITA car you buy a miata. And they found an excuse in the process that some folks like to think is wonderful and impartial and all to put a little more weight on it. So... Whatever. Whether you call it a rear DW adder or a process change because of a different stock hp rating or whatever the hell you want to call it, it sure seems like everyone is starting with "the miata is dominant, lets figure out a way to get more weight on it".
Mark
Just as mind boggling as the reluctance to move the MR2 and and potential 'correction' to the ITB Accords back to 25%. One case we have the sheets but we ignore, the next case we have the sheets so we fight for change...
No it's not easy. Nobody said it was. The ITAC does it's best to determine if there needs to be two spec lines or one. They research, they collect data from classification requestors. If they miss something that comes of age later, they correct it. I simply don't see how this is a problem. Other than 'it's not easy', I haven't read one single 'other side'.
And I am ALL FOR dyno sheet adjustments. It's fair and the right thing to do. But as we tried to codify when I was on the ITAC, at what threshold do you trigger an adjustment? This mid-way between 25% and 30% is 2whp people.
My suggestion has always been the nearest 5%. 10, 15, 20, 25, 30, 35, etc. Until you hit that next level, you stay the same. It eliminates the dyno noise and demonstrates enough of a difference to warrant a change yet still be 'stable'.
Howdy,
Well, its good that 'correct' is in quotes.
I think the point regarding "how will the ITAC know why the hp bump was there" is a good one.
This process is NOT going to be perfect. In this case it seems like you're arguing more for the sake of making one tiny part of the thing perfect for one particular car without thinking about all the rest of the imperfections and ignoring that the end result is a reasonable weight on the car.
I don't see how the process should include "figure out if the hp gain was due to an IT legal modification and then if so 2nd guess the manufacturer" unless we're talking about a _big_ miss. In this case, its an 80 lb miss (assuming you're right about why it changed) and its in a direction most people seem to be ok with.
Whatever.
Mark
Andy, your a good friend, and I love you man and all that stuff but this right here is a problem.
"It's not easy" means we have a much higher chance of screwing things up and geting them wrong.
Manufacturers LIE about stock hp. They get it wrong. And they aren't clear or are deceptive about why changes were made. And we are supposed to dive into that and figure it out?
As far as the known hp side of the process goes, I think it is rather simple. When we have accumulated enough data for a car to be weighed using known hp, we do that. And then we don't change it just because a new dyno sheet comes in. We change it if our 'on track" trigger causes us to look at the situation again, take another look at new dyno data, and give it another go.
Using the known hp numbers we have, this car is light. Not a lot, but some. After this change, I hope it is never touched again unless/until we have a true overdog situation on track -- and we do not, even at 2380 and even though the car is slighlty light.
Hey peter keane - in case you missed it on roadraceautox.com -
[Overt profanity edited out. This ain't RRAX - GA]
tnord edit - GO SIT ON AN UPSIDE-DOWN STOOL AND TRUCK YOURSELF!
the rest of you can fill in the blanks of what REALLY happened from there.
OK, we will agree to disagree on what is right based on it's relative difficulty.
So see my post above in response to Kirk's. I am all about dyno-weighting when the info is there. There is plenty of info that suggests 27% on 128hp. Where I think you are making a HUGE mistake is trying to slice and dice 2-3whp. You need to set up thresholds. At these HP levels, the nearest 5% is enough but not crazy.