July FasTrack posted

[Andy Bettencourt]

First off, Greg is not correct in his statements on the conversation we had. Car were not being adjusted based on on-track performance. We did not add any 'fudge-factor'. That term is one I have used for the first time here in this thread.

Some cars make more power in IT trim than others. Some are horribly underated from the factory. We take knowledge we have and we apply it to the best of our ability. If we used a strict formula, the seperation between the haves and the have-nots would be huge. It takes away all the 'good' that has happened to IT over the past 3 years. I buy into the belief that 'everything should be the same for everyone' but in practical application, we have to do our best - and that means deviating from a 'formula' and using some subjective factors and real data when we know them to be true. I realize that some of you think that is stupid, opens us up for judgement and critisism - but that is the way the current ITAC/CRB think - and we take our licks for it. For Joe to say the 'wool is being pulled over our eyes' is just foolish. I can't see how he can claim he doesn't question the integrity of the group and say that at the same time.

Kirk, you have to understand that the lower power car was classed first. Then a real-world look was taken on the second car. What say you to the TR8 example I described? If you say that the first car should gain weight - then I repect the fundamental position, but I think it's wrong. Common sense must prevail - and I think it did.

Whatever side you fall on, it's one of fundamental beliefs - and I think the success of IT has to do with the ones the ITAC and CRB currently hold. If we were to go by a formula, each IT class would be a one-trick pony. No debate.

The ITS RX-7 would be 2580 lbs
The ITA CRX would be 1957 lbs
ITB would be dominated by the 12A RX-7 at 2146 lbs

Sound good to everyone? :bleh: At what point do you apply something you know in an effort to make things fair?

[Joe Harlan]

Actually, the "process" weight for the BMW at 189 stock flywheel hp would have been lower than 2800 lbs if I recall correctly.

What got the BMW to a process weight of 3100-3200 lbs was......drum roll...a subjective fudge factor based on the real world reality that this motor made significant gains in IT trim.

So, if we use a straight "stock hp" calculation and that ONLY, then you rpobably end up with a BMW at a weight at which it is back to being a class killing overdog.
[/b]

Wrong again Jeff.

[JeffYoung]

How so? I know for a fact that expected hp gains on the BMW are what put its process weight at 3100 lbs +

What I don't know for a fact is what its process weight would be running a straight calculation of the stock reported hp (which was low in and of itself by the way, BMW is notorious for that)

[spnkzss]

I am not trying to add to the fire, I am truly curious. How else would you do it if it weren't for some "fudge" factor, or more importantly on track performance. You can't base things purely on hp/tq numbers. Double wishbones, disc vs drum, better aero. Things liek that will always come into play and some of that stuff won't be seen until the car is built at 10/10ths. The 90 CRX is identical to the 90 Civic except the CRX can add rear discs, and has better aero. Yet they both weight the same. Their may be a base to allow the Civic to drop some weight, but until you see it on track, how will you know for sure. You can theorize all day long, but until something is tested you won't know for sure. By they way, the added weight the the CRX didn't seem to hurt it much. Especially in the WDCR.

Then again SCCA said that they wanted to give everybody a place to race. They didn't say they wanted to give everybody a place to win. Some cars are just going to be better then others and I guess that is just the fact of the matter. I dunno.

[dj10]

and a couple hundred from the BMW 325 and let it run unrestricted in ITS because that's what the process calls for.

[/b]

Oh Gheez!!!!!!!! Have I been running in the wrong class (ITR) this year?

[JeffYoung]

Dan, I think all BMWs make 100hp more than stock, and should run in GT1 only.

I'm kidding.....

How are the racing efforts going this year?

[Joe Harlan]

How so? I know for a fact that expected hp gains on the BMW are what put its process weight at 3100 lbs +

What I don't know for a fact is what its process weight would be running a straight calculation of the stock reported hp (which was low in and of itself by the way, BMW is notorious for that)
[/b]

What you are missing is there is more than one divider and has to be. gains for vtec and vanos are going to be different than the gains for FI v Carb in and 2 valve v 4 valve. Known issues do have to be considered and I agree with that. I don't have a problem considering all those things. My issue in this case is that those things were not properly factored when when squeezing two different models into one classification. ANd if they were then the ITAC should have errored on the conservative side and based the new classification on the NEW KNOWN base HP number.

[JeffYoung]

Joe, I think we fundamentally agree but I don't think you understand my point. I think we both agree that the "process" cannot be entirely objective due to the factors you mention.

I was using the 325 to illustrate this. If you just used a straight "stock" BMW hp number to calculate the BMW's weight -- AND NOT TAKE INTO ACCOUNT VANOS, EXPECTED IT GAINS, ETC. -- you get a much lower weight than is "fair" for that car and the class. I agree with you that you have to take those things inot account, and when you do the process weight is 3100 lbs + (or something like that).

I guess where we disagree is on this point. I do agree that in a perfect world, the 94 Miatas should have been run through at 133 hp, instead of 128. I just don't think that the 5 hp difference matters that much and in my view (at least until I saw Greg's post about this maybe equaling 100 lbs or so, which is right on the border of what I - subjectively - consider signficant) is within the range of background noise for the process.

Hope that is clearer.

[Joe Harlan]

Joe, I think we fundamentally agree but I don't think you understand my point. I think we both agree that the "process" cannot be entirely objective due to the factors you mention.

I was using the 325 to illustrate this. If you just used a straight "stock" BMW hp number to calculate the BMW's weight -- AND NOT TAKE INTO ACCOUNT VANOS, EXPECTED IT GAINS, ETC. -- you get a much lower weight than is "fair" for that car and the class. I agree with you that you have to take those things inot account, and when you do the process weight is 3100 lbs + (or something like that).

I guess where we disagree is on this point. I do agree that in a perfect world, the 94 Miatas should have been run through at 133 hp, instead of 128. I just don't think that the 5 hp difference matters that much and in my view (at least until I saw Greg's post about this maybe equaling 100 lbs or so, which is right on the border of what I - subjectively - consider signficant) is within the range of background noise for the process.

Hope that is clearer.
[/b]

Much clearer. Think about the fact that in a low HP car that is a 4% difference in models. At what percentage do we pay attention? Again even that is not enough to get me wound up. I am of the belief that the 94/to 3 of 95 model had lower compression and that is how the lighter weight was calculated. I am working on those answers today.

[JeffYoung]

Good points, and sorry I was not clear before.

Let me know what you find out about the hp issue. 5 hp could be significant, I frankly just don't have enough race experience to say whether it is or isn't. Open to hearing more on this. We do a need a "line" fo what is objectively significant.

Of course, drawing that line is subjective......

[seckerich]

Oh Gheez!!!!!!!! Have I been running in the wrong class (ITR) this year?
[/b]

Quit lurking and go back to sleep.

[Chris Wire]

Greg, and I don't mean this in a disrespectful way, but in my view, there is absolutely no way to remove some subjectivity from the process. You can just run straight numbers on horsepower and weight, but that would be unfair to cars like yours, and mine, that have decent numbers and other huge handicaps (drum brakes, live rears, struts, etc.)

Once you agree that a straight hp/weight calculation (using ONLY stock hp and ONLY stock weight, and not "expected IT gains" or "expected IT weight" which woudl again involve subjective evaluations) won't work, then you can't get around having some fudge factors involved.

To me, what we have now is the lesser of many evils. We have as formulaic of a process AS IS POSSIBLE and a decent and well meaning group of guys trying to defend it. There will always be "fudge" decisions that not everyone agrees with, but that is the nature of having a group of human beings make decisions.
[/b]

Agreed 100%

Could not have said it better myself.

But I can see the GA/JH point, I just don't think it will be the gun that kills the golden goose.

See if I have this right:

ITS RX7
Early car - 146 hp
Late car - 160 hp
Weight using process based on 160 hp.

ITA Miata
Early car - 128 hp
Late car - 133 hp
Weight using process based on 128 hp

That's the argument right? The Miata received something that other cars in the process didn't? OK. I can appreciate that argument. However, given that there are "adders" and "hp gains in IT trim", and that both of those are subjective assumptions based on the best available information, do we really think that it's possible to balance the IT field using a TOTALLY objective formula (as opposed to a "process")? Or that we would even want what that would result in?

I don't believe so. And I thank Andy, Jake, and everyone else for putting in the time to get it as right as I currently believe it to be.

And BTW, I always understood that the restructuring would be a "process", rather than a strict "formula".

[Knestis]

To clarify something, Jeff - I don't think anyone is proposing using JUST stock published HP to determine race weights.

I also (personally) have no objection to the concept of "adders" or "subtractors" based on physical attributes of the car - IRS, rear discs, aero drag (NOT just Cd, which is a dimensionless derived factor and means NOTHING without considering frontal or other area measurements), variable valve optimization systems, six-speed gearboxes, flux capacitors, or any number of other substantive, observable characteristic of the car.

The ITS RX-7 would be 2580 lbs
The ITA CRX would be 1957 lbs
ITB would be dominated by the 12A RX-7 at 2146 lbs[/b]

...and to trot out rotaries as examples of how "a formula won't work" is disingenuous in the extreme. That's an entirely different type of powerplant, about which a good body of knowledge HAS been accumulated. But there's a world of difference between "rotaries gain XX% in IT trim" and "the Protege is known to have particularly lousy exhaust port configurations" (or whatever). The NX reportedly gets VERY lucky in this particular respect, and gains from the allowable porting but that doesn't mean that it should have a different power-making multiplier applied for the purposes of defining race weights.

Because the point at which the unit of granularity for adjusting factors used in the "process" becomes individual make/model examples, we are headed right down the path after Production."

I just threw out an old email exchange w/Andy ("So you call it a competition adjustment?" I think it was titled) in which I made exactly the same argument. The point at which our "knowledge" about things like how much power a car makes or how good it handles, is in terms of what has been demonstrated on the track, setting weights based on that information proactively is functionally no difference than post-hoc adjustments based on winners and losers.

Spanky - there's a ton of history here but you need to buy a beer for some folks who have been around long enough to watch what that does to a category over time. The short version is that driver skill, budget, testing, engineering development, and time spent have a much greater impact on competitiveness than do the mechanical attributes of a given car. If you want to get lead on your Borgward because someone somewhere has built a really good one and kicked someone else's butts with HIS Borgward, that's great. Particularly if you don't know if his Borgward is even legal. But I've watched that work and do NOT want to have any part of it in IT.

K

[JeffYoung]

Kirk, as always, good points.

To clarify mine - once you agree that we can't exclusively use objective numbers (and stock hp and weight aren't even that really, since we can argue about BMW reporting low hp numbers) we have acknowledged that there has to be some subjectivity in the process. We then end up with arguments like this -- how much fudge is ok? is a 5 hp difference significant? what cars have demonstrably better hp reactions to IT gains than others, etc.?

These arguments are in my view necessary evils. I will debate with folks over WHAT subjective factors should be used (as few as possible) and WHEN (as infrequently as possible), but to say that the system needs to be 100% objectice is (in my view, subjectively..lol) asking for something that is impossible to achieve.

I agree with Chris. RIGHT NOW, our system is been run in a way that for me anyway, works. ITS in the SEDiv is booming. Cars are equal, and competitive. I've seen fast Z cars, fast RX7s, fast Acuras, fast Miatas, even fast BMWs, and I like it.

If we went to a purely objective system, we'd have a class killer in every class, and that would not be healthy.

I do fully admit and agree that this system is open to corruption.

[Knestis]

What you are calling "fudge" (I think), is what evaluation geeks like me think of as "error." That's the slop in a measurement (plus or minus) around some value, that we just can't chase out. It's the "plus or minus 3%" that you hear about when survey results are cited on the news, or the tolerances that represent "close enough" when we take a part to the machine shop.

If that's the case, then YES - there is a point at which the weight (it's the output of the formula) is "close enough," too. To my mind, 50# is pretty damned close - 2% on a 2500# car? Heck yeah. Upwards of 5% starts to get "real" in a hurry though, I think.

And I don't give a damn (Scarlett) about individual car's "hp reactions to IT gains." If it's the difference between rotary and piston pumps - significant mechanical attributes? Sure. Years ago when I started agitating for a "formula," I argued for using displacement as the input, rather than stated HP, perhaps with considerations for technology (e.g., EFI vs carb vs those crappy hybrids in between).

I think the "killer in every class" is more of a fear than a demonstrated reality but I sure do appreciate how we want to avoid that. Problem is, subjectivity brings its own set of evils and i worry more about the power of that to mess things up.

BUT to be clear - right NOW, things are better than they've ever been. All the better reason to try to keep it that way.

K

[JeffYoung]

A healthy debate, Rhett....or is it Ashley? That's a joke......sorry, a bad one.

Just three quick things to clarify my thoughts here:

1. When I say "fudge" I perhaps mean it in a sloppy way that encompasses two ideas: (a) the natural error that occurs in processes that you mention AND ( the subjective factors that the ITAC used in adjusting weights on IT cars. I think both are necessary parts of the process. You can't ever entirely get rid of (a) fudge. You have to have ( fudge to smooth out any obvious inequities that the system/process can't account for objectively.

2. And one of the key ones there is the gains a motor realizes in IT trim. My car is a prime example. If you took my stock power (133), and ran the process, you'd get some ludicurously low weight that would (as my car becomes increasingly competitive) not be fair to the rest of IT. I think my weight is fair as is, but it is WAY higher than what the process would generate at 133 hp. E36 also had gains like this. So too do rotaries. All of these cars need to have a mechanism that reigns them in some, otherwise you'd have, as Andy notes, ITB RX7s running all over the class...or a return to the 210 whp E36s that almost killed my class.

This to me is a necessary, and subjective (although I think the present ITAC has done a great job in using documented examples only) factor that must be concerend.

3. Class killers from the objective process. It's real. I was in a class that had one. If you use BMW's stock hp of 189 crank (instead of documented 205-215 whp) to get to a process weight for the E36 of 2850 lbs then we have a big problem.

We agree on your last point. IT is ROCKIN'. In no small part due to the stuff that gets thrashed around on this board. So many thanks to the guys who participate in the civil debate here.

You going to hillclimb in Banner Elk in August or is Pablo now afraid of la montangas grande?

[WillM]

GawDAMMIT, another one of those stupid Miata memes that always suck me in.

"Better aero"??? Where in the WORLD are you guys getting that the aerodynamics of a Miata are poor and the NX are good? All "you guys" claim the aero on a Miata is poor, yet it's a small, round package, smaller and more aerodynamic than just about anything out there. Have you actually SEEN this size and shape of my car (or its brother, the Sentra SE-R)? You actually think the aerodynamics on my car are "good"?

I suspect "you got this from looking at Road and Track Cd results on the original car, when it was tested using a soft top. Clue: Cd is a relative term, and is not a direct indication of the amount of pounds-force of total aerodynamic drag (what REALLY is important here). And, last I heard, you're allowed to use a hardtop, making it an even nicer aero package.

I'd LOVE to see some data on this supposed Miata "aero" disadvantage.[/b]

So, if you want to get into a semantics pissing match let's handle it this way: I rescind my statement that the Miata is aerodynamic, compared to other vehicles. Ergo, we are left with the original claim that the Miata has poor aerodynamics.

Prove it.

You guys just can't seem to accept that the world doesn't revolve around you...
[/b]

The real Cd of a 1990-1997 Miata, with top, is 0.38, which agrees with my gut feeling that the aerodynamics "suck". Topless, the Cd is 0.44, which also agrees with my gut feeling that the top-down aerodynamics "really suck".

The 0.38 and 0.44 numbers were provided by Bob Hall "The Father of the Miata", from Mazda's California design studio.

[Knestis]

Argh.

Cd is NOT aero drag. Read up before you make statements about something.

K

[Jake]

... seem to eliminate barriers to addressing some of the 'tweener cases, where individual makes/models can't be reclassified downward without exceeding the maximum weight allowed for a given roll cage tubing size.

[/b]

Perhaps we should.... oh nevermind...

[Z3_GoCar]

Oh yeah, I forgot to mention the Z3 was ORIGINALLY clased at 2675....the adjusted to 2600....

Still doesn't seem remarkably different from a Miata to me....except the weight
Back to your debate.
[/b]

Not to mention mac struts in the front and antique trailing arms in the rear. You'd think that at the weight they classed it at you'd be seeing 160hp at the wheels on your dyno-pac.

Kessler built and 135hp 136tq?? sounds like you've got big gains there class killer :P