ITB - what a bunch of crap

[CRallo]

doh! wrong button!!

where is the wall bash smilie when you need it??

guess I'm making up for the lost time while I was at work... ugh

[Knestis]

An aero factor is likely unworkable. To work back to actual drag, we'd need Cd and frontal area values. It's hard enough to get the data we already use...!

K

[shwah]

An aero factor is likely unworkable. To work back to actual drag, we'd need Cd and frontal area values. It's hard enough to get the data we already use...!

K

Someone better tell the Scirocco guys that.

[R2 Racing]

Uh, you're using the wrong inital hp on this one, it should be 133hp. I know that the gain was from an upgaded ecu. Two things, you could update to the new ecu, secondly, there's still got to be more to be had even in the stock ecu. The results are:
133*1.3*14.5 = 2506 50lbs for A-arm = 2556 => 2555lbs

The process for the 94-95 ITA Miata was as such:

128 * 1.25 = 160 * 14.5 = 2320 + 50 for DW = 2370. Tried to give it 50lbs in total BS 'it's a Miata' weight but the cage rules maxed it out at 10lbs at the time, hence the 2380. Should really be 2370.

I've seen this discrepency before in relation to this car, and it irks me. Lets hear it from those who know - what's the utmost "stock" power one of these cars ever legally made as defined on the "Mazda MX-5/Miata includes R (94-97)" line? Is it 128, is it 133, or is it something else? Just so everyone knows who might not, I race a '92 Integra. That's where my personal knowledge resides. It's spec line is "Acura Integra (90-93)". The 90-91 made 130hp and the 92-93 made 140hp. Do I ever claim that the car should be classified at anything less that 140hp? No, because anyone who races one will set it up with the right combination of stock and legal parts to make it a "140hp" Integra. If I follow this logic that the 1.8L Miata was apparently done at, I should be claiming that the Integra should weigh (130*1.25*14.5) + 50 for 4WI - 50 for FWD = 2356lbs. Yeah, I'd like my 240lb weight break now. See, I too can make a 200lb difference. I mean come on, lets be honest here on what the car was capable of with stock parts, and what it's capable of "adding" in IT prep. I'm very honest with mine:
(140*1.28*14.5)+50-50 = 2598lbs. Actual is 2595lbs. Like I said before, "spot on".

[dickita15]

An aero factor is likely unworkable. To work back to actual drag, we'd need Cd and frontal area values. It's hard enough to get the data we already use...!

K

Besides any aero data available would be with windows up and stock ride height. Event the small GT class guys know they can not deal with aero calculations.

[JeffYoung]

Arguments over which IT car has better, aero, whehter 128 or 133 is the stock hp number, whether 25% or 35% is the correct gain factor, etc. etc. etc. etc....sure starting to look prod like to me......

[Andy Bettencourt]

I've seen this discrepency before in relation to this car, and it irks me. Lets hear it from those who know - what's the utmost "stock" power one of these cars ever legally made as defined on the "Mazda MX-5/Miata includes R (94-97)" line? Is it 128, is it 133, or is it something else? Just so everyone knows who might not, I race a '92 Integra. That's where my personal knowledge resides. It's spec line is "Acura Integra (90-93)". The 90-91 made 130hp and the 92-93 made 140hp. Do I ever claim that the car should be classified at anything less that 140hp? No, because anyone who races one will set it up with the right combination of stock and legal parts to make it a "140hp" Integra. If I follow this logic that the 1.8L Miata was apparently done at, I should be claiming that the Integra should weigh (130*1.25*14.5) + 50 for 4WI - 50 for FWD = 2356lbs. Yeah, I'd like my 240lb weight break now. See, I too can make a 200lb difference. I mean come on, lets be honest here on what the car was capable of with stock parts, and what it's capable of "adding" in IT prep. I'm very honest with mine:
(140*1.28*14.5)+50-50 = 2598lbs. Actual is 2595lbs. Like I said before, "spot on".

Kev - Here is what we used for facts in making the decision: and we can use this description to point to whenever this comes up again.......

The 94-95 car was requested for a re-class - it was in ITS. The 96-97 wasn't even in the ITCS at that time IIRC. The process was run and 2380 spit out as I have shown above.

Then a year later, someone requested the addition of the 96-97 car to the spec line. The cars had different stock hp levels. There are now 3 choices.

1. List the 96-97 cars seperately @ 2460
2. Change the weight of the people who had been running and list them on the same line @ 2460
3. Just add those years to the current listing at 2380

So now you look at what are the differences between the cars. Mechanically, from oil pan to air filter, the cars are identical. The 96 model year was the swap over to OBD-2. Knowing that Miata's run pig-rich and from much SM knowledge and contact with Mazda people, the only reason for the bump was because of the ECU.

So, now you have a stock hp bump that is exclusively due to an allowable modification in IT. So in fact, the 94/95 cars and 96/97 cas have the exact same power potential in IT trim.

Given all that information, and knowing that Mazda is notorious for overrating their stock hp numbers (See dyno sheets and reversed factory numbers on Miata and RX-8's) it was determined that the lower number was the most accurate and most appropriate number to use. The committee voted as such and I stick behind that decision as the correct thing to do.

It would be like a model getting a revised exhaust system as the exclusive change resulting in a 5hp bump when everything else is identical. Since the exhaust is free in IT, the two cars have the same exact power potential in IT - and it's the LOWER of the two numbers because the foundation for your build doesn't change. It's not like a cam change or an intake revision or a larger TB...

Keep this IMPORTANT fact in mind. The timing of the two requests was the trigger to scrub down the listings. Since one was already listed, the decision needed a harder look. Your Teg - like the 2nd gen RX-7 have different hp ratings on the same line...the engines are mechanically different and you are allowed to update and backdate because the chassis are the same. You say you run the best possible combination of stock parts - and you should - and the RX-7 guys do too. But in this case, there is NO CHANGE in stock parts. Since the ECU is/was free, there is no difference in power potential. If you bolted on all your go-fast goodies onto a 1990 Teg, you most certainly would NOT get the same result as if you used the 1993 guts.

If people still have an issue with this train of thought given all the information, the CRB could seperate the listings in the ITCS. BUT, nobody would run a 96-97 car because they know it is ONLY the equal of the 94-95 car and no better...AND with the VIN rule gone, everyone would convert to the earlier car so it's really moot.

Again, agree or disagree, I stand behind the decision as the correct thing and most accurate thing to do for this listing. I would vote as such with any make and model should the facts remain the same.

[dazzlesa]

before i go asking, what are the differences from the factory for the integra's

[JeffYoung]

Andy, I've been in agreement with your explanation since this issue first came up, and still believe you guys thought you were doing the right thing.

But isn't the error in the logic this. Weight is set based on STOCK hp, not POWER POTENTIAL. So even though the power potential between the two cars is the same, a non-stock number is being used to set the weight for the car, and that's not how the process is supposed to work.

I think the car needs to go through at the highest stock HP no. for all makes on the same line. I assume the 2nd Gen RX7 was treated the same way, and run through at 160 hp, correct?

[Greg Amy]

I think the car needs to go through at the highest stock HP no. for all makes on the same line.

Hell hath done frozen over: Young and I agree on something...

[Andy Bettencourt]

Andy, I've been in agreement with your explanation since this issue first came up, and still believe you guys thought you were doing the right thing.

But isn't the error in the logic this. Weight is set based on STOCK hp, not POWER POTENTIAL. So even though the power potential between the two cars is the same, a non-stock number is being used to set the weight for the car, and that's not how the process is supposed to work.

I think the car needs to go through at the highest stock HP no. for all makes on the same line. I assume the 2nd Gen RX7 was treated the same way, and run through at 160 hp, correct?

Actually Jeff, you are only half right. Weight is set using the stock hp level as the base, then a multiplier that estimates POWER POTENTIAL in IT trim. So in fact, the crank number that is used to multiply by the classes target PW/WT is indeed it's estimated potential. Given the cars have the EXACT SAME potential, they sould be listed at the same weight. Its what stock hp level you believe is the question - and given the facts and the timing of the requests, I believe 100% that 128hp is the correct number.

It would be like someone adding one final missing year to the TR8 spec line. Except that year had a 5hp boost due to a revised air cleaner - and nothing else. Since air filtration is open, would you accept unconditionally the additional 80lbs of minimum weight that saddled you with because of something that was already open in IT?

If you say yes, then you are a better man than I. (On edit - the RX-7 is a different issue, mechanically the motors are very different - resulting in a 16hp increase)

[JeffYoung]

If we are basing all weights on stock hp x a multiplier, yes, that is what should happen. This is just for consistency's sake. If we are using highest stock hp for all cars on a spec line for everyone, then we should use it for everyone.

P.S. -- that's actually exactly the case on my car. 80s made 133 hp with the carbs, 81s 138 with FI. The 138 number ought to be used.

[Andy Bettencourt]

If we are basing all weights on stock hp x a multiplier, yes, that is what should happen. This is just for consistency's sake. If we are using highest stock hp for all cars on a spec line for everyone, then we should use it for everyone.

P.S. -- that's actually exactly the case on my car. 80s made 133 hp with the carbs, 81s 138 with FI. The 138 number ought to be used.

Except you have a mechanical difference there that is NOT free in IT. Those cars have different power potentials in IT. The Miata's do not.

Again, we use what we know to most accurately class cars. In this case, we believe the 128hp number to be the correct one to use given the facts.

[JeffYoung]

Huh? FI is "free" -- I can update/backdate. It would be wrong to run the car through the process at 133 hp when the same car on the same line has a 138 rating.

No need to beath this one to death, I understand but disagree with your position.

Greg! We have ALWAYS been Miata haters......we'll always have Paris sweetie......lol......

[Gary L]

Except you have a mechanical difference there that is NOT free in IT. Those cars have different power potentials in IT. The Miata's do not.

Again, we use what we know to most accurately class cars. In this case, we believe the 128hp number to be the correct one to use given the facts.

And actually, this all boils down to judicious use of the multiplier. The question becomes... if the higher hp engine had been classified first, followed by the lesser, would the end result have been the same? In my (admittedly sometimes optimistic) mind, the answer is yes.

[Andy Bettencourt]

Huh? FI is "free" -- I can update/backdate. It would be wrong to run the car through the process at 133 hp when the same car on the same line has a 138 rating.

Correct, but your UD/BD changes the power potential of the car - just like the RX-7. So the weights should be based on the power potential. In your case, you have UD'd to a higher hp level without the added weight. That is NOT the case with the Miata.

If you listed the Miata's at 2460, it would be 80lbs of weight that COULD NOT be made up for because there is no gain in IT trim to that 5 hp. Refer back to my 'air cleaner' example.

Agree to disagree, yes.

[Knestis]

Arguments over which IT car has better, aero, whehter 128 or 133 is the stock hp number, whether 25% or 35% is the correct gain factor, etc. etc. etc. etc....sure starting to look prod like to me......

It could but it doesn't have to.

"We don't consider aero drag as a factor. Thanks for asking."

"All cars are classified using a 1.25 multiplier unless a preponderance of evidence collected from many sources over a period of years makes a compelling case for the ITAC to do otherwise. Regardless, 'IT power factors' used in classifying and specifying cars will be documented and available to the membership. Thanks for asking."

"For classification and specification purposes, the highest published stock power figure will be used for all years, trim levels, and option packages included on any given spec line. Thanks for asking." (I don't know WHY this wouldn't always be the case even now.)

K

[Knestis]

Andy, I've been in agreement with your explanation since this issue first came up, and still believe you guys thought you were doing the right thing.

But isn't the error in the logic this. Weight is set based on STOCK hp, not POWER POTENTIAL. So even though the power potential between the two cars is the same, a non-stock number is being used to set the weight for the car, and that's not how the process is supposed to work.

I think the car needs to go through at the highest stock HP no. for all makes on the same line. I assume the 2nd Gen RX7 was treated the same way, and run through at 160 hp, correct?

What Jeff said.

However, the rotaries are such special cases that any pretense that they don't get their own "process" is kind of silly.

K

[tnord]

so.....if the 96-97 miata was put on it's own spec line, and used a different power multiplier to get to the same weight (since we know the power potential is the same), would you guys quit your bitching?

[R2 Racing]

Thank you for the explanation, Andy. If that was ever been posted before, I missed it. Reading it, I understand your side of the arguement. But the idea of classing a car at less than it's maximum OEM claimed HP number still just seems wrong to me, no matter the reason for the max number. But I see your point, if the bump can be easily replicated under the IT rules by a lesser output model, everyone will run that lesser output model that will have been classed lighter. But that leads to another issue...

Hypothetically speaking, if the ITAC did decide to split the '94-95 and the '96-97 Miata's onto different spec lines at 2380 and 2460 respectively, why are both cars being calculated at the same 1.25 power adder? If what you say is true, that the only difference in stock power can be 100% made up within the IT rules, shouldn't the '94-95 have a higher power adder? Shouldn't it be more capable to make power within the IT rules than the '96-97? Seems like it absolutely should to me - there's more potential there in the ECU to gain power, Mazda proved that themselves. So why do they have the same power adder? If the power making differences between them can be completely made up within the IT rules, shouldn't the lower OEM rated model get a higher power adder, effectively resulting in both cars having about the same spec'd (higher) weight? I'm failing to see how that doesn't make sense.

before i go asking, what are the differences from the factory for the integra's

The bump in power on the '92-93's came from different cams and the move to OBD-1. As Andy is pointing out, that cam change is not something that could legally be done later on within the IT rules, so that's why 140hp was used for its classification, and not 130hp. That I understand.

But even with that, I can make the same arguement I just did for the Miata's, but in the opposite way. Again, lets hypothetically say that the ITAC classed the '90-91 and '92-93 Integra's seperately. If that happened, the '90-91 would not be legally allowed to "update/backdate" and run the '92-93 cams under IT rules and therefore would not get its 10hp bump. In this instance, you could use the same power adder for the two different classifications and come up with two different weights, because one has a specific power adding difference in it that the other cannot make up under IT rules. They would have to be spec'd at different weights in order to compete with one another. The Miata's would not, because they both should be making the same power in the end under the IT rules. The Integra's will not.


Andy, please don't think that I'm trying to single you out because you race this specific car. You're just very knowledgable about these cars, as I am with Integra's, and you're in the position to (and are willing to!) discuss with and explain this whole process to me. I'm learning a lot here on how these numbers are created, and that's a good thing. I get asked a lot at the track from other IT racers if I know how XYZ was decided upon, and I'm starting to figure that out here. Thanks again for the discussion.