Review and adjust weight of ITB CRX Si as appropriate

tom91ita

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CRB Letter Tracking Number #1333

ATTN: SCCA BOD, CRB, ITAC, ImprovedTouring.com May 11, 2010

I would like to make note of an error and/or omission in the assigned weight of the 1985-87 Honda CRX Si (as well as the 1986-87 Honda Civic Si). I am requesting that these weights be properly and actually evaluated. In the specific case of the 1985-87 CRX Si, this car was originally classified as ITA and was given an arbitrary 150 pound addition when it was reclassified as ITB. This weight is inappropriate compared to cars with similarly designed engines in the class as you will soon see.

One basic premise of IT classing takes into consideration certain aspects of power to weight and/or displacement to weight ratios. For example, ITB has used a factor of 17 pounds per horsepower and ITA has used 14.5 pounds per horsepower. This basic formula can be illustrated as follows for ITA:

Stock HP X HP Multiplier X 14.5 #/HP – 50 #’s (if FWD) + 50 #’s (if double wishbone type suspension)

However, there is a rather wide range when it comes to the Horsepower Multiplier. This is in large part due to the wide range of assigned horsepower ratings by the original manufacturers. However, if one looks at the IT expected Horsepower calculated from the assigned weights in the GCR, one can see that similar engine architecture results in similar specific horsepower ratings.

Four Cylinder - 16 Valve Engines

Four popular 16V cars are the 1988-91 Honda CRX Si, Acura Integra, 1.8L Mazda Miata (all ITA cars with the 14.5 #/HP factor) and the 1988-91 Honda Civic DX (ITB & 17 #/HP factor). These cars have the following Horsepower Multipliers (calculated from the GCR and published stock HP ratings).

Horsepower Multiplier = (GCR Weight + FWD adjustment – Suspension adjustment)/(Stock HP)/14.4

Honda CRX Si = (2250 +50-50)/108/14.5 = 1.4368
Acura Integra = (2595 + 50 -50)/140/14.5 = 1.2783
Mazda Miata = (2380+0-50)/133/14.5 = 1.2082
Honda Civic DX = (2240 +50-50)/92/17 = 1.4322

I think the above represents a rather wide range of Power Factors. However, if we consider what the HP per Liter is for the above, we see that the 16V engines all provide close to the same specific HP per Liter.

Honda CRX Si = 1.4368 x 108 / 1.590 Liters = 97.59 HP per Liter Estimated in IT Trim
Acura Integra = 1.2783 x 140 / 1.834 Liters = 97.58 HP per Liter Estimated in IT Trim
Mazda Miata = 1.2082 x 133 / 1.839 Liters = 87.37 HP per Liter Estimated in IT Trim
Honda Civic DX = 1.4322 x 92 / 1.493 Liters = 88.25 HP per Liter Estimated in IT Trim

The IT Trim specific output of the 1.6L CRX and the 1.8L Integra being essentially identical is not that surprising since the 1.8L is effectively a scaled up version of the 1.6L. Also, although the Honda Civic DX is significantly less than the other Honda based 16V engines, it should be noted that this is not surprising considering the car has a dual point injection system instead of the multipoint injection system.

If you prefer to look at the Integra and CRX in terms of #’s per CC, you will again see that they are essentially equal; (Integra = 1.411 #/cc and the ITA CRX is 1.415 #/cc).

Four Cylinder - 12 Valve Engines
There is a limited sampling of 12V cars in Improved Touring. However, there are three distinct engines and they are all Hondas and all in ITB. These are the 1986-89 Honda Accord, the 1986-87 Honda Prelude and the 1985-87 CRX Si. These cars have the following Horsepower Multipliers (calculated from the GCR and published stock HP ratings).

Horsepower Multiplier = (GCR Weight + FWD adjustment – Suspension adjustment)/(Stock HP)/17

Accord = (2550 +50-50)/120/17 = 1.2500
Prelude = (2450 + 50 -50)/110/17 = 1.3101
85-87 CRX Si = (2130+50-0)/91/17 = 1.4092

Again, the above represents a rather wide range of Power Factors. But what is rather unusual about this is that these engines are from a single company and have very similar architecture with the exception of the compression ratio.

So what does the HP Multiplier and IT expected HP work out to for these similar engines that are nearly scale versions of each other work out in terms of IT Trim Estimated HP per Liter?

Accord: 1.25 x 120 / 1.955 Liters = 76.73 HP per Liter Est. in IT Trim Comp Ratio of 9.3
Prelude: 1.3101 x 110 / 1.955 Liters = 73.71 HP per Liter Est. in IT Trim Comp Ratio of 8.8

The Prelude, with its lower Compression Ratio, has a slightly lower specific output. So how does this compare to the 85-87 CRX Si which has a lower CR still?

85-87 CRX Si: 1.4092 x 91 / 1.488 Liters = 86.16 HP per Liter Est. in IT Trim Comp Ratio of 8.7

So the 85-87 CRX Si with a CR of 0.6 less than the Accord is purported to make 12% more power per liter. Also, the 85-87 CRX Si 12 valve engine is purported to make HP/Liter ratios similar to the better breathing 16 valve engines.

If you look at these cars in terms of weight per displacement they are not consistent as well:

Accord: 2550/1955 = 1.30 # per cc
Prelude: 2450/1955 = 1.25 # per cc
85-87 CRX Si: 2130/1488 = 1.43 # per cc

Please note that the12V ITB CRX Si is saddled with more weight per cc than the last three ITA ARRC Champions. And the 12V ITB CRX Si also suspension limitations in that it has front torsion bar springs and a rear beam axle compared to the wishbone style of the other Hondas and Integras.

I believe that the power potential and power to weight factors of the newer and improved 88-91 Honda CRX Si were inadvertently applied to the 85-87 when it was moved from ITA to ITB. Because of this error, the weight should be reviewed as an error/omission.

If the ITB CRX were classed like the Prelude at 1.25 #/cc (after all, the CRX CR is even less than the Prelude), the CRX should weigh 1860 #’s. This means the CRX would be 270 #’s overweight.

It should be noted that I have been told privately that I am tilting at windmills with this request because there are certain ITAC members (and/or former CRB member) who either race the Accord or who race against the CRX that will prevent my car from ever having the weight classified fairly. I, however, think that this should not impact the fair review of the car. But because of this perceived potential, I would very much appreciate a technical reason as to why the CRX 12V motor combination is rated so differently than the other Honda 12V ITB cars.

I do not consider the standard style explanation of “Car is appropriate as Classed” to be an appropriate answer.

Thanks,

Tom
 
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reasonable well written, a fair argument with good use of supporting data, even though it is all from the GCR. the demonstration of the ITA miata and ITB Accord having advantageous multipliers, particularly when compared against similar architectures in the same class is quite revealing. good thing those 2 cars aren't power houses in their classes ;)

FWIW, though, the ITA teg 1.8L is NOT simply a scaled up version of the 1.6L in the CRX, but the point isn't lost on me.

good luck.
 
Tom,

While you certainly have the Miata calculation wrong (and I am not sure why you use architechtures in OTHER classes to prove your ITB example), I like the stratagy given the current climate.

However, please tell us what you believe a full-blown motor of your genre would put down to the wheels. Remember, we had Catch's data on file and I have some dyno data locally as well...

Take that number, divide by .85. Multiply by 17 and take away your 50lbs for a close representation. I estimate your car needs to make 109whp to be at process weight.

I HATE HATE HATE the like architecture method. The extreme example is the 2.0L 16V Nissan 140hp motor out of the SE-R vs. the 2.0L 16V 240hp motor out of the S2000. Does teh CRB really think we should be using the same multiplier for both??? If not, don't fall on your sword during con-calls...:(
 
reasonable well written, a fair argument with good use of supporting data, even though it is all from the GCR. the demonstration of the ITA miata and ITB Accord having advantageous multipliers, particularly when compared against similar architectures in the same class is quite revealing. good thing those 2 cars aren't power houses in their classes ;)

FWIW, though, the ITA teg 1.8L is NOT simply a scaled up version of the 1.6L in the CRX, but the point isn't lost on me.

good luck.

The Miata is based on 1.25 on 128hp and has been dabted many times. It also has 10lbs of slush weight added as well. The Accord is also spot on 25% and those who know the numbers know that is a VERY accurate depiction.

Is it possible the 1.5L Honda's are good at tight nimble tracks while the cars with a good bit more HP and weight are better at the big tracks? I bet the newer 160HP Civic Si is a screamer in ITA on the big end.
 
i tried to use the 16V's in ITA to demonstrate that there is not much difference between multipliers or #/cc even between makes. at least there is less difference there between different cars than between the 12V hondas.

is the crx more nimble on the small tracks? probably. does the accord have an advantage at championship quality tracks? probably.

frankly i was surprised by the ITA CRX and Teg having essentially exactly #/cc ratios to the 3rd decimal point.

the ITB CRX and Accord are rated from Honda at almost exactly the same power per liter, 61.2 vs. 61.4 HP/Liter respectively.

before i blew my built motor, i did not have it dynoed and have decided to not build another until i get an answer for this. i can't argue your number of 109 because i just don't know.

i also want to try and get a real response and not just the "car good as is" approach because i think there has to be real and rational reason.
 
Andy - I don't want to debate my feelings regarding the current state of classifications in IT in someone else's topic. if tom was wrong about the miata, then so be it - I have no dog in that hunt, and I feel that there are at elast a good handful of cars that can take it to the mazdas in ITA, so i'm not particularly worried about it (though it IS a very strong car being more than the sum of its power to weight ratio and established HP output). The 20A accord LXi/SEi, spot on or no, IS a VERY strong car in class - there are a small number of cars that can run with it, some are track dependant, some are not.

the point, however, is not if a miata or accord are spot on, it's why other cars are so far from spot on, as to make the "correct" cars better. The overall classifications appear pretty good in ITR/S/A, but in B they are all over the map. the 1st gen CRX, anything with a toyota 4age, 240 volvos, etc.. are all woefully overweight AND THAT CAN BE DEMONSTATED AND PROVEN just as the confirmation of an accord being "spot on" was.

I simply want to see the field classed a bit more equitably, so I applaud Tom for adding his efforts - the weight loss is deserved and hopefully will be granted. as you point out, the simillar engine architecture debate is not as cut and dry as simple displacement and valve count per cylinder. But we continue to use things like 130% for 16v cars in B when it's demonstrably incorrect and not relevant to Tom's inquiry. I know you left the ITAC, I bet you had issues with the CRB. maybe they were based on the above, maybe not. but the classification mysteries drive me nuts, and I intend to ramp up my efforts as a member to have them clarified.

oh, and the ITA 99-00 civic Si thing I DO have a stake in. agian, I don't want to debate, but that classification is, in my oppinion, a bad idea at that weight. I've already submitted a letter to the CRB and ITAC about it.
 
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i also want to try and get a real response and not just the "car good as is" approach because i think there has to be real and rational reason.

Well I am telling you the real and rational reason (accurate or not). When this car was reviewed with the Process the ITAC used from 2005-2009, it was estimated by the Honda experts on the committee that 109-110whp was achievable given a full-tilt legal build. Those numbers were then send upward through the process spitting out your 2180-50= 2130.

(I disagree with the following) The Process in ITB for 16V cars is a standard multiplier of 30% and 25% for all others when no power numbers are known.

The bottom line for you Tom to wrap your head around this fact: There is no rhyme or reason to the power numbers other than this: If you don't know the actual numbers, 25% is used most of the time. If you DO know power numbers, the ITAC tries to use them as accurately as possible. Just taking stock HP numbers and using those in your math is spinning your wheels because that number is just the BASE number and really isn't what is placed into the equation.

Where I do like your arguement (although you won't get anywhere if you have no data to dispell the 109-110whp) is that the CRB has started using like architecture. Look for 12V motors with similar cc's to compare with.

I can tell you that more than 1 ITAC/CRB member at the time this went to 2130 thought it was going to ruin ITB.
 
Andy - I don't want to debate my feelings regarding the current state of classifications in IT in someone else's topic. if tom was wrong about the miata, then so be it - I have no dog in that hunt, and I feel that there are at elast a good handful of cars that can take it to the mazdas in ITA, so i'm not particularly worried about it (though it IS a very strong car being more than the sum of its power to weight ratio and established HP output). The 20A accord LXi/SEi, spot on or no, IS a VERY strong car in class - there are a small number of cars that can run with it, some are track dependant, some are not.

My point was simple, don't use different architetures from different classes to prove a point.

the point, however, is not if a miata or accord are spot on, it's why other cars are so far from spot on, as to make the "correct" cars better. The overall classifications appear pretty good in ITR/S/A, but in B they are all over the map. the 1st gen CRX, anything with a toyota 4age, 240 volvos, etc.. are all woefully overweight AND THAT CAN BE DEMONSTATED AND PROVEN just as the confirmation of an accord being "spot on" was.

The 1st Gen CRX can be debated on it's accuracy. Like I said above, the classification was based on 'actual' numbers, not estimates. Hardly an anomoly in the ITCS.

I simply want to see the field classed a bit more equitably, so I applaud Tom for adding his efforts - the weight loss is deserved and hopefully will be granted. as you point out, the simillar engine architecture debate is not as cut and dry as simple displacement and valve count per cylinder. But we continue to use things like 130% for 16v cars in B when it's demonstrably incorrect and not relevant to Tom's inquiry. I know you left the ITAC, I bet you had issues with the CRB. maybe they were based on the above, maybe not. but the classification mysteries drive me nuts, and I intend to ramp up my efforts as a member to have them clarified.

The Toyota issue was certainly one that led to my frustration and resignation. An unwillingness to do the right thing on that car was and is, unacceptable. Proving a negative is very hard but with all the data, this car should not have been classed at anything over 25%. ITB has the most 'legacy cars' that people care about. The other main issue I had with the CRB is the unwillingness to accept and implement changes based on the Process. Right or wrong, at least those numbers would make sense to everyone. And of course the mechanisms were and are there to correct an error should one arise (none in 5 years).

oh, and the ITA 99-00 civic Si thing I DO have a stake in. agian, I don't want to debate, but that classification is, in my oppinion, a bad idea at that weight. I've already submitted a letter to the CRB and ITAC about it.

Agreed. The car can make ITS weight and doesn't belong in ITA.
 
Tom, while there are some similarities between the '86 & '87 Honda Prelude si and the 120 HP Lxi, there are certainly differences. In fact, that Accord was run through the process which stated it was spot on weight wise. Then the Prelude was run through the process yielding a different weight than the existing 2,450 lbs: somewhere about 110 lbs less than current weight in fact. Maybe some guys who were on that call could expand upon how that conclusion was made. Oh, they did have numbers from my a pro engine build among other power adder goodies on the Prelude. It was acquired from another source and people can't say I only provided them my second best results.

By the way, the last sentenece in the above paragraph is SO HUGE to me. They can actually explain where the conclusion was derrived from to us.

I did submit the Prelude si to be reviewed a while back. For better or worse, all I wanted was to have that and others to be measured by the same stick. The error & omissions / how it came down from ITA is an interesting approach, one that I had thought of too. Yeah, several cars came down from ITA which if the CRB wanted to they could probably pass under this loop hole if you want to call it that.

I do applaud your effort and think this letter can't hurt. I don't think it solves the issue, and wish more people would be vocal. I'm actually quiet disappointed with how few letters the CRB & BOD received about getting parity within the classes. I know they're sick of hearing from me. LOL

The Civic si - it's gonna be a pig in ITA. I can understand why the requester wanted it in ITA at the heavy weight given the inventory of SSC civics. Just got a Civic si off scales yesterday. 1,721 pounds on the front wheels, 1,044 on the rear (2,765 total). Great.
 
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The Civic si - it's gonna be a pig in ITA. I can understand why the requester wanted it in ITA at the heavy weight given the inventory of SSC civics. Just got a Civic si off scales yesterday. 1,721 pounds on the front wheels, 1,044 on the rear (2,765 total). Great.

our ITS civic has 28lbs of lead in the floor and weighs 2430 with 200lbs driver and ~1/4 tank of fuel. the difference in cgae weight is ~25-40lbs depending on the tube size / wall used in the larger weight cars vs 1.5x0.095, assuming ~80ft of material. the car can make weight in S, even if it starts as an SSC car.
 
It seems to me that ITB has changed in the last couple years. Now it is "ITB Plus". The formula that classified the Accord, and the VW mk3 just isn't consistent with the performance envelope of the older B cars.

Until recently many considered my Volvo 142 an "Overdog" in ITB. Now I hear it is due a weight reduction if run through the "Process" with the current classification formula. I guess the CRB and ITAC let the balance slip in my class.

Maybe correcting the "Process" and reigning in the new hot ITB cars would be a better option.
 
As long as the cars are treated equally, whatever process being used is fair, makes sense, explainable. With such a HUGE diversity of cars, budgets, and drive abilites, IT shouldn't be looking towards on-track performance as anything but a trigger to look closer into things. Do these things and that's fine Charlie.
 
It seems to me that ITB has changed in the last couple years. Now it is "ITB Plus". The formula that classified the Accord, and the VW mk3 just isn't consistent with the performance envelope of the older B cars.

Until recently many considered my Volvo 142 an "Overdog" in ITB. Now I hear it is due a weight reduction if run through the "Process" with the current classification formula. I guess the CRB and ITAC let the balance slip in my class.

Maybe correcting the "Process" and reigning in the new hot ITB cars would be a better option.

Each class had bogey cars that power to weights were set around when the Process was created. New classifications and reclassifications were done using these bogey numbers. From what I hear from ITB experts on the CRB and ITAC, the numbers that were used for the Volvo were based on motors that had some common cheats that proliferated the Volvo's at the time. The IT community got wind of and were reversed. I can't validate any of that but I can tell you that is what I have heard. So the Volvo may be a touch behind number-wise based on that. Just another car to fix that the CRB won't touch.

There is nothing wrong with the Process. Especially now that there are real checks and balances. The CRB just has to let the ITAC USE it. That is what your letters should be saying when you write in.
 
There is nothing wrong with the Process. Especially now that there are real checks and balances. The CRB just has to let the ITAC USE it. That is what your letters should be saying when you write in.

Andy is right ... we believe that we have a way to make fair and consistent adjustments to cars, but we can't use it. The basic reason is that the ITAC who presided over the great realignment in 2005 got approval for making changes to weights and classifications, and they did so with the agreement that the adjustments would be a one-time event. There was no sanction for making any changes to already-listed cars beyond that. They went so far as to write language in the rulebook to prevent any future ITACs from doing what they did.

Yes, the ITAC ignored their own rules and agreements for quite a while there, and the powers that be looked the other way for that period. That era has ended, and the rulebook rules the day, as it were. Therefore, these weights are not going to be changed (except for the obvious errors, examples of which I've posted before) unless the rules change, and there's a rule-change process, and we have to follow it.

The uphill part of the rules change battle is that there is a general opinion that IT is in a really good spot right now, even ITB, although maybe there are a few things that aren't perfect. If we REALLY want to go down the road of adjusting everything, there are going to be a LOT of adjustments and our current members who are happy with the status quo (most of whom are not "politically involved" and do not post here) might very well end up unhappy. Those are the people that show up every weekend and really enjoy the racing, not much caring about this hub-bub about weights and processes and politics. I know a lot of those people. Put another way. sometimes fine-tuning something that works pretty well messes it up. It's a risk, and this would be taking a risk with one of the club's best assets. So if you're going to make the argument for such a rules change, please address that concern.

Taking my ITAC hat off and speaking personally now: I'm trying to help and I'm sympathetic. These are the boundaries of our abilities right now. Either make arguments that work within them, or work to expand them. Otherwise, it really is tilting at windmills.
 
Andy is right ... we believe that we have a way to make fair and consistent adjustments to cars, but we can't use it.

You can use it. The CRB won't approve the weights set that way. You've got two options - cave to the foolishness that the CRB has created or put two fingers in the air, classify and correct cars in a manner that makes sense to the ITAC and let the CRB be the bad guy.

The ITAC's job is to classify cars as best as they can. Kowtowing to the CRB on the classification/correction issue isn't doing that and is a disservice to the IT community.

It all depends on whether one wants to play the part of P. Henry or V. Quisling. There really is no middle ground on this.

Therefore, these weights are not going to be changed (except for the obvious errors, examples of which I've posted before) unless the rules change, and there's a rule-change process, and we have to follow it.

Except the so-called rulebook hasn't been followed. The BMW 320i was reweighted, outside the 5-year window and in direct conflict with the official policy of the CRB. You want to explain the reason why the CRB broke their rules on that car and not the others?

The uphill part of the rules change battle is that there is a general opinion that IT is in a really good spot right now, even ITB, although maybe there are a few things that aren't perfect. If we REALLY want to go down the road of adjusting everything, there are going to be a LOT of adjustments and our current members who are happy with the status quo (most of whom are not "politically involved" and do not post here) might very well end up unhappy. Those are the people that show up every weekend and really enjoy the racing, not much caring about this hub-bub about weights and processes and politics. I know a lot of those people. Put another way. sometimes fine-tuning something that works pretty well messes it up. It's a risk, and this would be taking a risk with one of the club's best assets. So if you're going to make the argument for such a rules change, please address that concern.

Things are not fine in all of IT. ITC is dead, though there is little anyone can do about it. (Though, I will note that at least one ITC competitor was told to pound sand when he asked that his car be reclassified in ITB so he would have someone to race against). ITB is starting down the road of spec Golf and the ITAC knows it.

The folks don't care about weights, process, et al won't give a damn if the CRB lets the ITAC fix the problem in ITB.
 
You can use it. The CRB won't approve the weights set that way. You've got two options - cave to the foolishness that the CRB has created or put two fingers in the air, classify and correct cars in a manner that makes sense to the ITAC and let the CRB be the bad guy.

Not my style, you need someone else for the job if you want to play us vs. them. I'd rather work together in a fashion that at least works.

Except the so-called rulebook hasn't been followed. The BMW 320i was reweighted, outside the 5-year window and in direct conflict with the official policy of the CRB. You want to explain the reason why the CRB broke their rules on that car and not the others?

From memory, that one met the operational definition of error. It is the same engine as the late 2002, with an effectively identical chassis layout/suspension, and yet it was MUCH heavier than that 2002. The 2002 was considered to be the "correct" listing as it was on the "bogie list" during the realignment, so the 320i was adjusted to match. (It could have been made even lighter to exactly match the 2002, but instead it was adjusted to its process weight, which is pretty close to the 2002, but the 2002 isn't exactly at its process weight either.)

BTW, things were still very much in flux at that time ... but it meets the definition of an error.
 
Josh, I seriously appreciate your efforts and what you're attempting to do. I do feel that you are doing what you feel is right. I also truly thank you for having the guts and taking the time to post here. Communication is important. Thank you.

All that said, we do have issues in IT and even more so in other SCCA categories. To turn a blind eye saying that things are good here, we'll continue on this way is a pretty weak option. I don't understand why we set the bar to good, or even pretty darn good when we have the tools to make this great. The CRB wants or feels the need to evaluate based upon on track performance. Fine, that MAY work in categories where there are only a few different makes / models. IT is far from that case.

If what Charlie said is true (which I too have wondered if the bar was raised in ITB when the Golf was classed), every single car classed from today on hurts cars previously classed before this new standard was established. Sorry dude, but that sucks. Andy talked about the Volvo receiving a weight based upon cars that were not legal. I'm not saying it's right, but people will feel justified in pushing the envelope in terms of legality which in turn impacts other areas. Oh, there we go again with using on track performance as a weak bench mark.

Don't think that because many other people are silent about all of this they don't care. Why don't they speak up? Not sure and will have to visit the history books to get a better feel for that one.

If the goal of the CRB or the powers that be is to shut people up like me, it's slowly working. Congrats and good luck with the future. Oh gesh, there's SO MUCH irony in all of this.
 
Josh, not being confrontational but you used the phrase 'definition of an error' twice in your last post. Can you tell us what the 'definition of an error' is? It will help if we know what that definition is.
 
If what Charlie said is true (which I too have wondered if the bar was raised in ITB when the Golf was classed), every single car classed from today on hurts cars previously classed before this new standard was established.

Don't think that because many other people are silent about all of this they don't care. Why don't they speak up? Not sure and will have to visit the history books to get a better feel for that one.

If the goal of the CRB or the powers that be is to shut people up like me, it's slowly working. Congrats and good luck with the future. Oh gesh, there's SO MUCH irony in all of this.

Yup nothing to say here... well except that Peter and Chris... well nevermind.
Stephen
 
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