April 08 FastTrack is up

[DavidM]

1. When do you proactively re-evaluate a car? Do we develop a schedule?
2. What if you can't find the data? How much digging is enough digging?
3. I am asking YOU this. How much evidence is enough to CHANGE a car that has been classed?
4. Again, I am asking you to answer these questions. How small a data is worthy of a weight change?
5. Addressed above
6. You missed this one

His point Andy is that the ITAC has already answered these questions when they decided to class cars using real numbers. I asked the same question in the previous thread and I don't think ever got an answer. The ITAC would've had to answer 1-5 of your questions in order to class cars with real numbers, so what we're the answers?

The ITAC has set a precedent by classing cars using real numbers and they had better be ready to accept the consequences of doing so. You can't just do a one-time re-evaluation using real numbers for some cars and then say you're never going to do it again. You can't classify some new cars using real numbers because there's data on similar cars, but use the standard 25% on other cars because there's no data. In order to be fair to the cars classed using real data you need an on-going process to re-evaluate cars.

I would say you re-evaluate a car every X years starting X years after the car is classed. 3 years seems like a good number to me. We have a ton of already classed cars, so you spilt them up into thirds and start a rolling evaluation of each third. That's a lot of cars, but the ITAC already has info on most of them, right? All that has to be done is look at the existing info and see if there is any new info.

Race results are a starting point for "evidence". We don't like to use race results as performance indicators, but this is exactly how most of the cars for which real numbers were used were singled out. Dyno sheets are obviously a good source of info. Seems like you'd have to have a dyno sheet in order to know the real world numbers, no? Of course, now that people know the ITAC will use real numbers to classify cars people probably won't be so open anymore. It'd be an interesting exercise to rent a dyno for, say the ARRC, and then require all the IT cars to do some runs (right after qualy). I'm sure there'd be lots of bitching and moaning, but the results would be interesting.

The size of change required for the change to be implemented should be tied to a percentage of the cars classed weight, not some static change like 100 lbs. If the weighting based on the real world data results in a change of X% from the car's current weight then the weight gets updated. 100 lbs is 4% and 50 lbs 2% for a 2500 lb car.

As for proving negatives, I don't think the ITAC does anything about that now so how would that change? Has a car ever been classed using less than 25%? If your car can't make the 25% then maybe you should find another car.

David

 

[shwah]

1. When do you proactively re-evaluate a car? Do we develop a schedule?
2. What if you can't find the data? How much digging is enough digging?
3. I am asking YOU this. How much evidence is enough to CHANGE a car that has been classed?
4. Again, I am asking you to answer these questions. How small a data is worthy of a weight change?
5. Addressed above
6. You missed this one

Read the words below my listed answers on my last reply too.
1. I actually described proactively developing a schedule in my post. X years after classification look at the cars that you didn't know enough about to do anything else but assume 25%.
2, 3, 4, Sorry Andy. The ITAC has already found a way to answer these questions and take action on some cars already. I don't need to provide a recipe for what you have already done. It may in fact be different answers for each case. You won't be able to write a spreadsheet to do the whole job, just like you can't use one to do the whole classification job.
5. I missed this one on my last reply as a separate item, it was in my response though but you review every car that you blindly assume 25% gain on.
6. I answered this one as 5 the first time.

 

[Andy Bettencourt]

Guys, I know the ITAC's answers, I am trying to get you to think about what you would do and how you would set this whole thing up if it were you singularly making the decision. I know how much data *I* would like to see in order to validiate it as real - how about you?

Just because we have done stuff a certain way before - or haven't done anything about some things as well, doesn't mean ANY of it is right. YOUR IDEAS are what I am looking for.

I agree that lap times and wins can be a trigger for sure. It is certainly a trigger for a PCA.

I also like the idea on % or car weight. Makes it a lot more fair to the lighter guys.

 

[shwah]

OK. I get the point.

To be honest I need to stop and think about this for a while. A few days or weeks even. I just don't know if the issue can be institutionalized. By definition each one of these will be a special case. There needs to be some sort of criteria to identify or flag a need for a closer look though.

EDIT - I do hope however that you can understand the frustration of seeing this approach applied already, in the recent past, and then being asked to define how and when it could be applied.

 

[Knestis]

I worry that these conversations presume (hope?) that every car in the discussion was run through the same process, by the same people, at the same time. That's just not the case. If we could start with a blank slate, there would certainly be fewer inconsistencies.

K

 

[Bill Miller]

The Golf IV is: 20.4 lbs/hp in STOCK form at spec weight
The Golf III is: 20.4 lbs/hp in STOCK form at spec weight
The Golf II is: 21.7 lbs/hp in STOCK form at spec weight
The Golf I is: 23.1 lbs/hp in STOCK form at spec weight

Look at that list this way Eddie

Golf I: 18.4 lb/hp using 25% gain over stock (90+23=113) @ 2080#
Golf II: 17.4 lb/hp using 25% gain over stock (105+26=131) @ 2280#
Golf III: 16.3 lb/hp using 25% gain over stock (115+29=144) @ 2350#
Golf IV: Assumed to be same as Golf III

These should be reasonable, for the cars in question, as other than that, they're about the same. If anything, the G III and G IV cars should have larger brake adders, so they're really even lighter compared to the G I and G II cars.

Looking at the Golf I, in order for it to be 'in line' w/ the class benchmark for ITB (16.5 lb/hp), it would have to make 126hp in IT trim, or a 40% gain over stock. I've been playing w/ these cars for a looooong time, and I can tell you this w/ 100% certainty, there's no way you get that kind of squeeze out of a 1.8 JH motor in IT trim. Even if you assume a 30% gain, because of the crappy stock exhaust manifold, that puts you @ 117hp and a ratio of 17.8 lb/hp. That's pretty close the current Golf II numbers. The same analysis on the Golf II, to get to a ratio of 16.5 lb/hp puts the output in IT trim @ 138 hp, or a 31%+ gain. Don't see that happening either.

I have to ask though, since the Golf I was run through the process, and did get a weight adjustment, how did it land where it did? Do people really think these cars see a 40% gain in IT trim?

And just for fun:

Protege: 18.4 lb/hp using 25% gain over stock (103+26=129) @ 2375# in ITC
Protege: 16.6 lb/hp using 25% gain over stock (103+26=129) @ 2140# in ITB

 

[Bill Miller]

I worry that these conversations presume (hope?) that every car in the discussion was run through the same process, by the same people, at the same time. That's just not the case. If we could start with a blank slate, there would certainly be fewer inconsistencies.

K

Kirk,

It's my understanding that when the 'great realignment' was done a couple of years ago, that _most_ of the current members of the ITAC were there.

/edit/ And I'm not sure if you realize it or not, but you've made a good case for documenting and publishing the process.

 

[Andy Bettencourt]

OK. I get the point.

To be honest I need to stop and think about this for a while. A few days or weeks even. I just don't know if the issue can be institutionalized. By definition each one of these will be a special case. There needs to be some sort of criteria to identify or flag a need for a closer look though.

EDIT - I do hope however that you can understand the frustration of seeing this approach applied already, in the recent past, and then being asked to define how and when it could be applied.

I understand fully your point, and I am getting the feeling you understand mine.

 

[Dave Zaslow]

Having owned and raced an A1, and owning and racing an A3, I have gone back and looked at the hp/weight ratios of the two cars. With the new A1 weight there is not a lot of difference. I cannot speak to the A2. I would seek out Chris Albin as the go-to person in all things A2.

I hereby authorise Andy to get my dhipped A3's HP & Torque readings from the dyno runs done on Bob Dowie's rig, for ITAC internal use only.

Now please add weight to all Honda's !!!!!

DZ

 

[gran racing]

Come on Dave, I haven't picked on the Golf IIIs for a few months now. (My letter was from this fall.)

 

[Knestis]

>> /edit/ And I'm not sure if you realize it or not, but you've made a good case for documenting and publishing the process.

Yup. And not by accident.

We started a spreadsheet prior to last night's ITAC call to record the math and considerations for the cars that are spec'd. Since we are using a process, there's all kinds of good reasons to record how it gets used and the assumptions that underly the decisions that get made during its use.

While at least some of the current ITAC folks were involved in the Great Realignment, record keeping doesn't seem to have been the strong suit of the organization in the past.

K

 

[BlueStreak]

Looking at the Golf I, in order for it to be 'in line' w/ the class benchmark for ITB (16.5 lb/hp), it would have to make 126hp in IT trim, or a 40% gain over stock. I've been playing w/ these cars for a looooong time, and I can tell you this w/ 100% certainty, there's no way you get that kind of squeeze out of a 1.8 JH motor in IT trim.

I have to ask though, since the Golf I was run through the process, and did get a weight adjustment, how did it land where it did? Do people really think these cars see a 40% gain in IT trim?

Thanks Bill, at least someone appears to see my point. Further, when you factor in CIS vs. ECU control, there is a significant difference in performance potential between the cars as weighted. At least I now know 40% is the improvement target - back to the dyno until I make 126. (now where did I put that Audi throttle body - I'M KIDDING!)

 

[Bill Miller]

>> /edit/ And I'm not sure if you realize it or not, but you've made a good case for documenting and publishing the process.

Yup. And not by accident.

We started a spreadsheet prior to last night's ITAC call to record the math and considerations for the cars that are spec'd. Since we are using a process, there's all kinds of good reasons to record how it gets used and the assumptions that underly the decisions that get made during its use.

Nice to hear

While at least some of the current ITAC folks were involved in the Great Realignment, record keeping doesn't seem to have been the strong suit of the organization in the past.

K

Given all the gnashing of teeth that went on before hand, ESPECIALLY over the lack of any kind of documentation on how car weights were determined (not to mention other little goodies, like the Quad 4 rear brakes )it's a real shame that better records weren't kept.


Eddie,

I've got just a little bit of background w/ this one.