August 2011 Fastrack

[Knestis]

Don't know enough to support one way or another but last time I talked to Les he was there in support of his friends ITB honda. Les was there with his FP volvo but from what I remember on track shennangans made it it easy for him to skip out on the race.

Curious was this a process move? of recently both the CRX and the Civic in ITB have lost 160lbs.. How much data was presented to get such a reduction? how many 10/10ths builds were handed in to get the percentage correct?

With respect, the whole "10/10ths build" thing was never the big deal that it's been made for you around the Toyota question. I think you've been led astray by post hoc rationalization of a weight spec on the MR2 that's based in bias and fear.

The Process v.2. simply asked the ITAC members to record their judgment of whatever evidence was presented for a non-standard - other than 1.25 - power multiplier. The idea from the outset, from a guy who helped craft that system, was to impose a pretty high expectation of confidence from the entire committee in order to shift us off of "SOP" and on to "what we know." If we had repeated dyno evidence of a reputable, pro build, that would have been taken into consideration differently than "I've never put it on a dyno but my friend built it and I know it makes like 120whp."

(I hate the term "what we know," by the way, because we NEVER actually KNOW anything.)

The actual change for the CRX Si happened after I left but we looked at a pretty good accumulation of evidence that generated substantial confidence around a 1.3 multiplier for that make/model (with 91 hp stock). Not coincidentally, that multiplier puts it at its current GCR weight. The Civic version should have been done at the same time but wasn't.

You are going to drive yourself crazy looking for a way to make classifications more generally - or the Process v.2 as it was applied c.2008-2010 and should still be applied - align with what happened with (or to) the MR2. That listing is crap. It's always been crap. It should be fixed. Until it is, my confidence in the ITAC is very low.

K

[Bill Miller]

With respect, the whole "10/10ths build" thing was never the big deal that it's been made for you around the Toyota question. I think you've been led astray by post hoc rationalization of a weight spec on the MR2 that's based in bias and fear.

The Process v.2. simply asked the ITAC members to record their judgment of whatever evidence was presented for a non-standard - other than 1.25 - power multiplier. The idea from the outset, from a guy who helped craft that system, was to impose a pretty high expectation of confidence from the entire committee in order to shift us off of "SOP" and on to "what we know." If we had repeated dyno evidence of a reputable, pro build, that would have been taken into consideration differently than "I've never put it on a dyno but my friend built it and I know it makes like 120whp."

(I hate the term "what we know," by the way, because we NEVER actually KNOW anything.)

The actual change for the CRX Si happened after I left but we looked at a pretty good accumulation of evidence that generated substantial confidence around a 1.3 multiplier for that make/model (with 91 hp stock). Not coincidentally, that multiplier puts it at its current GCR weight. The Civic version should have been done at the same time but wasn't.

You are going to drive yourself crazy looking for a way to make classifications more generally - or the Process v.2 as it was applied c.2008-2010 and should still be applied - align with what happened with (or to) the MR2. That listing is crap. It's always been crap. It should be fixed. Until it is, my confidence in the ITAC is very low.

K

Kirk,

This is in no way a reflection on you, or directed at you, but based on things I've been told by various former ITAC members over the years, the bolded part really made me chuckle.

Here's what I believe is the math for how the 1G CRX Si/3G Civic Si's got adjusted to their current 1970lbs:

91hp * 1.30 * .98 * 17 = 1970.8

Tom Lamb's letter languished in the ITAC for years. I wrote mine over the winter in support of his and adding some new points of my own. It was well established the old weight was completely arbitrary when the car was moved down from A to B.

BTW, that previous weight of 2130lbs was a power multiplier of 40%+.

Rob,

The math seems right.

This math however, doesn't

90hp * X * .98 * 17 = 2080 lbs

Or, rearranged to solve for X:

X = 2080 / (.98 * 90 *17) = 1.39

And another:

90hp * X * .98 * .17 = 2130 lbs

X = 2130 (.98*90*.17) = 1.42


The second set of equations is for the 1.8 8v VW Scirocco II. That's a car w/ a 1.8L 8v SOHC engine running CIS. The first set of equations is for the Rabbit GTI. Same chassis as the Scirroco, just a square back vs a slope back, like the Civic Si / CRX Si.

It's well accepted that there's no performance advantage of the CRX body over the Civic body, in IT trim, yet the Rabbit / Scirocco pair is saddled w/ a 50# weight penalty for the slope back body (it's 60# for the 1.7 ITC versions of those cars). I realize that these differences pre-date the GR and were based on some perceived aero advantage, but it seems like such an obvious error and easy correction today.

In light of Jeff's comments, I'm not sure why the 1.39/1.42 power factor hasn't been addressed.

Let me try to cover as much of the above as I can.

1. On the ITB Hondas. When we finally got the "go" to "reprocess" cars, we looked at the ITB CRX based on Tom's letter and others. The existing GCR weight (I can run th calc if someone wants) seemed to have no rational relation to any of the existing gain modifiers. So, honestly, in the absence of any real data, that car should be at 1.30 default rather than the 1.45 or whatever it was at.

We looked at Tom's data (which included dyno information if I recall correctly), Rob's and others. I'm not a Honda or ITB guy but the guys on the committee who are agreed we were not looking at a motor that would make ITA CRX gains.

So the vote was put it at default, or 1.3, for the class. The Civic then followed.

We do have to get away from the notion of "why did you lower weights on cars that are already competitive?" We had that discussion on the ITAC, but once you put something like the Process in place you have to trust it and use it. And that is what we did.

[tom91ita]

Bill,

i would agree with you that the math you outlined does not seem right. that was the basic method i used to arrive at us having a 1.42ish mulitplier. we (ITB CRX si's) had one HP more than your 90 and we had 50 #'s more (2130 vs. your 2080).

my letter writing started in 2008 and continued in 2009 and 2010 and again in 2010 & then the website submission tool/method. one of the things that really bugged me was the 2008 request was not acted on and later i was told that i had missed a deadline. not that i submitted it too late but that they did not review/respond in time.

i recommend you submit the math/methods you outlined above.

did that vintage VW also drop from ITA to ITB about the same time the CRX moved? just curious if it was given an arbitrary amount of weight as well.

good luck (hope that does not sound sarcastic).

i really do wish you well!

[Bill Miller]

Bill,

i would agree with you that the math you outlined does not seem right. that was the basic method i used to arrive at us having a 1.42ish mulitplier. we (ITB CRX si's) had one HP more than your 90 and we had 50 #'s more (2130 vs. your 2080).

my letter writing started in 2008 and continued in 2009 and 2010 and again in 2010 & then the website submission tool/method. one of the things that really bugged me was the 2008 request was not acted on and later i was told that i had missed a deadline. not that i submitted it too late but that they did not review/respond in time.

i recommend you submit the math/methods you outlined above.

did that vintage VW also drop from ITA to ITB about the same time the CRX moved? just curious if it was given an arbitrary amount of weight as well.

good luck (hope that does not sound sarcastic).

i really do wish you well!

Tom,

I took your comments as sincere and genuine. Thanks. The 8v 1.8 VW's have been ITB cars since the mid to late 90's.

I've been banging the VW drum for a LONG time, just ask anyone that's been around here for a while.

I have also championed an objective, repeatable classification process for IT cars for about as long as I've been on this site. (Has it really been 10 years???? )

I am truly glad to see where IT has come in that time, although it was a rough road.
A few folks put in some long hours, did some very heavy lifting, and often times got crap for it. They deserve a lot of credit for getting things done in the face of some tough (and often well connected) opposition.

[Andy Bettencourt]

The math doesn't have to be 'right' when you have an accepted WHP number. If you 'know' 115whp, it might come out to .32 or .27 or whatever.

Not saying this is the case here but the numbers don't always have to fit in a box to be 'correct' per the Process.

[Bill Miller]

The math doesn't have to be 'right' when you have an accepted WHP number. If you 'know' 115whp, it might come out to .32 or .27 or whatever.

Not saying this is the case here but the numbers don't always have to fit in a box to be 'correct' per the Process.

Andy,

I don't think anyone disagrees with that, or disputes it. I know I certainly don't.

However, per the ITAC Operations Manual, it's pretty well outlined what has to happen if you're going to use "Known Horsepower"

Known Horsepower
In this method, the horsepower number published by the manufacturer is ignored, and instead, the expected horsepower comes from another source. These days it is pretty common to have dynamometer results, usually from a chassis dyno. For chassis dynos, the ITAC standard is that RWD cars have an 18% drivetrain loss (from crank to wheels) and FWD cars have a 15% loss. Thus, for example, if a RWD car is “known” to make 150 horsepower on a chassis dyno, then the “expected horsepower” for power-to-weight calculation should be 150/.82, which is 183. Care should be taken that the highest dyno numbers seen are used, and that cars classed by this method should be at the limit of the IT rules.
In order to use this method, an ITAC member should put together a set of documentation that proves what the maximum known horsepower is. Then each member should say how confident he/she is in the documentation, considering the source, how well-prepared the measured cars are, etc. If the average confidence is 75% or greater, then the “known horsepower” method may be used to derive the expected horsepower.
A 75% confidence level is a pretty high level. It is expected that the committee would bring with them a healthy amount of skepticism when it comes to reviewing dyno sheets. One should take into account the source of the info, the shop that ran the dyno, information about how well-prepared the car and the engine car, who did the build, and any hidden motives of anyone involved in providing the data. In the best of circumstances, dyno results are hard to trust as they can be extremely variable even when all conditions are the same. It is reasonable to look at on-track results of the cars in question to see if the perceived acceleration matches what the dyno sheets appear to say.
All dyno sheets should be posted to the thread on the letter-tracking site that is associated with the letter under discussion. That way all information associated with the decision is saved and findable. The letter number is known by the author and also published in Fastrack. Any CRB or ITAC member can then find that letter number in the system and find all dyno sheets associated with its weight decision.

If that's followed, the 'alternative' multiplier will be well documented, and supported by data and a confidence vote by the ITAC

On the ITB Hondas: I understand that when a reprocess request comes in they look at it. It SEEMS to me that just because they can't make the numbers make sense, they have to understand that they are based on a previous decision and data. Just because that info is not under their nose doesn't mean it doesn't exist. I hope that they are assuming the number is correct and looking at data to prove that it ISN'T instead of ignoring the weight, starting from scratch and saying, do we have anything other than this letter - and then changing it. To me, that would be very short-sighted.

And there's the rub. I'm sure that deviations from the process were based on data and prior discussions. However, if that information was not archived and preserved, you (the ITAC) have two choices, either re-compile it and follow through with the "Known Horsepower" process, or, lacking that, follow the "Published Horsepower" process (essentially starting from scratch).

If you see Jeff's earlier comment that I quoted and bolded, you'll see that he states in the absence of an real data. Jeff's an ITAC member, and from what I can tell, a pretty thorough guy. I firmly believe that if the data and documentation used to determine the initial 2130# weight for the 3rd gen Civic/CRX Si were available, he (and the other ITAC members) would have used it.

So, I don't think anyone was short-sighted. I also don't think it's incumbent on the ITAC to disprove variations from the process that don't have supporting documentation. In fact, to not run a car through the "Published Horsepower" process, when the required "Known Horsepower" documentation and confidence vote is not in place, is subverting and 'going outside' the process.

This is why archiving prior decisions is so important. I believe Josh and the rest of the ITAC recognized this, which is why it was codified in the Ops manual.

As Jeff said, once you put something like The Process in place, you have to trust it and use it.

[JeffYoung]

I personally am not assuming the old weights are "correct" fi they don't follow the 15/20/25/30/35% gain ladder. If they don't that smacks of the weight just being POOMAed. The ITB CRX/Civic seems to be a prime example of this.

For these VWs the biggest issue is that no one with any knowledge about the motors has written in to request a reprocess. I know (literally) nothing aobut these cars and would need some one to put pen to paper in a formal submission to the ITAC before I'd be comfortable doing anything with them.