June 2012 Fastrack

Adding to what jeff says.

some cars DON'T make 25%
some make MORE than 25%

some hp numbers change, sometimes because of "IT" legal changes to the car as stock, sometimes because of component part changes, sometimes because the OEM lied and got called on it...

SAE changed power rating certicfications to "certified" in ~2005. see the brochure. lots of cars "lost" hp after this change, toyota and honda most notably.

years ago, SAE went from Gross to Net hp. some cars we only have good info for in DIN. mostly these are the old and slow (i.e. ITB) cars, but they still come up and they still must be dealt with.

Mazda over reported power on later miatas with variable valve timing and RX8s. ford has gotten caught doing the same at least once. it happens, and we dont' always know about it.

put all of that together, and you can see that "25% over lowest number" isn't an objectively better rule than "25% over highest number"

the miata fell in the middle. we moved it up. love it or hate it, that's what we did.

we are STILL looking at the MR2. I've got one, so I'm not trying to look liek I'm playing favorites, but it is frustrating.

the Accord... I'd rather not discuss.
 
JeffYoung said:
Chris S. -- I see you still don't get the meaning of "modify." So it goes. In any event, we consider your proposal, spent a fair amount of time debating it, and crafted a rule that gave you what you wanted while at the same time addressing some concern our folks had. That rule is clearly written and says if you the rules allow you to modify/alter a part of the harness, but not remove it as a part of an allowed removal of an attendant part, you keep the original redundant wiring. Chip laid it out well. I would think a "thanks for working on my request in your free time and on weekends" would be appropriate here, but I know that's not the Internet way.
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Jeff - maybe it seems more clearly written to folks that participated in the discussions. Of course I appreciate the time and effort that the ITAC puts into this and every other issue. I probably don't say that enough. Sorry about that.

If you look at the resulting rule with a fresh set of eyes, it sure looks a lot more complicated than it needs to be.

That will bring different interpretations from different folks about things like "modify" allowing the addition of completely new pieces rather than changing existing ones. Is there some perceived risk/advantage to removing wires that do not carry current in an engine harness versus any other point in the car? If there is already a rule stating that something cannot be removed, doesn't that make it ineligible for removal if we just say if a wire does not do anything within the rules, and is not specifically required by the rules you can take it out?
 
Chip42 said:
put all of that together, and you can see that "25% over lowest number" isn't an objectively better rule than "25% over highest number"

the miata fell in the middle. we moved it up. love it or hate it, that's what we did.
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And the point is because you actually have the information, you don;t have to be objective. You can be CORRECT.

Unprecedented to reset a weight to above what the dyno sheets tell you. It's a great day in IT.
 
Andy Bettencourt said:
First off, this classification is NOT inconsistent with the way other cars are classed because it is DIFFERENT. Read that again. It's different. I am going to lay out some generic scenarios for you in an effort to try and reduce the Miata bias.

Take car A. Car A had a body style run from 1990-1993. From 1990-1992, it had 130hp. In 1993, they tweaked the intake manifold and the cams and the new rating was 140hp. Now, if the 1990-1992 car was classed first, it would be classed based on the 130hp number. You would then have a choice as the CRB. Add another spec line because the cars are different, or combine them at the higher HP because the items that make the extra 10hp are not legal to change in the lower HP version - and then allow the UD-BD so that the lower HP car can actually make a real base number. Following me? It's a mechanical change that CAN be done to can extra HP in IT trim.

Now, take car B. Car B had the same body style run and the same HP change. But the extra 10hp came from a tuned set of headers and a low restriction exhaust. Are we saying that the new stock HP is the way to class this car. HELL NO. Why? Because those mods are already taken into account in the IT weight calculation. Follow this logic:

Lets say for arguments sake that there are 4 things that contribute to a cars 25% potential increase in IT trim (just using round numbers to make it easy. We know every car responds differently). Air intake 5%, exhaust 10%, B&B - port and compression 5%, and ECU 5%. There is your 25%. If a car gets a bump in stock HP SOLELY because of one of these, you have not increased it's potential HP in IT trim. You can not argue this. In the above example, all you did was erode the 10% increase in an optimized exhaust, you did not add 10hp to the baseline number. So you COULD use the higher number to class it but you would then have to reduce the potential % gain the car will get - netting the same original weight.
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I have NOT read all the threads in this thread but I wanted to quickly point out that this IS NOT DIFFERENT than what has been done in the past. I am sure you have not forgotten the Audi yet have you? I will not Re-Hash the past for those that don't know, use the search function and you will see that this is EXACTLY the same scenario with the same outcome.

Take car A or B. Car A and B had a body style run from 1990-1993. From 1990-1992, it had 130hp. In 1993, they tweaked the car in some way (doesn't really matter how) and it now has 140hp. Now, if the 1990-1992 car was classed first, it would be classed based on the 130hp number.
WHAT IF THE 1990-1992 car NEVER EXISTED... then how would you classify the 1993 car? I suspect that if the 90-92 car never existed then the 1993 car would be classed heavy based on the performance increase that it is capable of (based on your arguement) which results in cars like the MR2.


I hate to say this but I honestly think this is consistant within the class AND it is not different than past decisions.

Stephen
 
Andy understands the details of the situation well, and the specifics are important.

Nobody has pointed out an example that is exactly the same as the Miata.
The Camaro that Rallo points out was NOT classed, and THEN had a new year added to the spec line with a higher hp number. That car was a cluster, and there were people on the CRB that did NOT want it in IT. (One member felt it was too easy to cheat up. He demanded high horsepower be used to base our math on, and a high torque adder, in order to 'counter' the cheating 'issue'. That car leaves a bad taste in my mouth because I feel like there was a 'deal' made. OK, if we use a high factor, and a high tq, can we at least classify it?. The ned result is actually lower than some people wanted. As Jeff says, committee work is about compromise)

Other examples trotted out here are not relevant because the changes have been mechanically based, (intake manifolds, etc) that aren't IT prep items.

When we hashed this out in committee, it was codified that this was essentially the first such car with this unique set of circumstances and timing, and that going forward, if the situation arose again, it would be handled the same.

I'm bothered that the CRb saw fit to charge the ITAC with reversing itself.
I'm also bothered that the ITAC rejected the Double Wishbone on the rear driven wheels adder when Andy brought it up in committee, and later when it was proposed. We hear how the Miata is greater than the sum of its parts...a gestalt car. 50/50 weight distribution and the double wishbone rear are factors mentioned time and again. Well, my RX-7 is 50/50, and trust me, it aint no miata! I understand the desire to keep the process simple, but this DW adder is so black and white and so relevant, I'm sad it didn't get incorporated.

What really happened here is that clearly the CRB member(s) decided the Miata was too much game for (the Mosers?) on track, and pushed the ITAC to figure out a way to add weight. Sorry, it's soo easy to see between the lines. The power thing is a convenient excuse.
 
Andy Bettencourt said:
And I am ALL FOR dyno sheet adjustments. It's fair and the right thing to do. But as we tried to codify when I was on the ITAC, at what threshold do you trigger an adjustment? This mid-way between 25% and 30% is 2whp people.

My suggestion has always been the nearest 5%. 10, 15, 20, 25, 30, 35, etc. Until you hit that next level, you stay the same. It eliminates the dyno noise and demonstrates enough of a difference to warrant a change yet still be 'stable'.
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I haven't read through this whole thread, but ... Andy, I think you still don't fully understand the use of dyno-based weight assignments.

When you use a dyno-based weight, you STOP TALKING ABOUT STOCK HP AND PERCENTAGES. You use either approach A or approach B, not a hybrid. Approach A is stock horsepower + a percentage, and approach B is you use dyno horsepower corrected to crank hp.

If you choose to use dyno results, you just use them. You don't then go back and compare that number to stock, or "pick a percentage gain". You just use it.
 
tom91ita said:
Jake,

i agree with most everything but i think this is independent of the Mosers.
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Mmmm, I dunno. Read the thread over on RRAX. An awful lot of talk about one or two ARRC races. Add that to some comments by a former ITACer, and reading the current ITACers statements, and ....Smoke...fire...and all that.
 
JoshS said:
I haven't read through this whole thread, but ... Andy, I think you still don't fully understand the use of dyno-based weight assignments.

When you use a dyno-based weight, you STOP TALKING ABOUT STOCK HP AND PERCENTAGES. You use either approach A or approach B, not a hybrid. Approach A is stock horsepower + a percentage, and approach B is you use dyno horsepower corrected to crank hp.

If you choose to use dyno results, you just use them. You don't then go back and compare that number to stock, or "pick a percentage gain". You just use it.
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Are you reading Andy to be saying that you DO use a number when you know it, BUT, that he thinks that you only use it if it bumps the gain 5%? Thats what i'm reading.

So, I THINK he's saying he'd like to see a hp bump of about 6 or so (based on 5% of 130), before he'd want to use it. (Because 2-3hp is dyno noise)
 
So the formula is based on a 25% hp improvement over Stock 1.8L hp or is that advertised 1.8L hp or dynoed 1.8L HP or crank HP or Wheel HP? I ask because I've never seen a 128-133HP stock, factory fresh Miata.... ever.

My original 92 miata 1.6 was listed at 116hp but on a dyno it peaked at 97hp.
I'll make the assumption that the 1.8's are the same. That car now has a 2001 VVt engine that is claimed to be in the 145hp range stock, but mine with I/H/E and ecu just barely makes 144 peak. So the claimed number and real numbers don't seem to be very accurate.

Some of us are new to this and weren't around when all the initial arguing was done.

I was pissed off about this initially because of the randomness of it. If changes are made to the weight of the car why not wait until the end of the year or prior to the beginning of a new season? You know during the off season when people are working on their cars anyway.
 
preparedcivic said:
Another example, and this one should be near and dear too:

ITA 2nd gen CRX Si. '88-90's were advertised at 105hp. '91's at 108. We all know they make way more than 30%. That would be an interesting one to see the weight math on.
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Hi Rob,

Not sure if this got answered already... the 2nd Gen CRX is an example of "backwards math" to arrive at the weight. During the Great Re-alignment, the Si was determined to be "the bogey" for ITA performance. The ITAC used "what we know" dyno examples of the car to determine how much the engine was under-rated from the factory and therefore bump the weight by 110#'s, IIRC.

All of this is by my best recollection and I wasn't heavily involved in the technical side of The Process at the time... anyone else can feel free to chime in with additions/corrections.

Christian
 
JoshS said:
I haven't read through this whole thread, but ... Andy, I think you still don't fully understand the use of dyno-based weight assignments.

When you use a dyno-based weight, you STOP TALKING ABOUT STOCK HP AND PERCENTAGES. You use either approach A or approach B, not a hybrid. Approach A is stock horsepower + a percentage, and approach B is you use dyno horsepower corrected to crank hp.

If you choose to use dyno results, you just use them. You don't then go back and compare that number to stock, or "pick a percentage gain". You just use it.
Click to expand...

I agree. But when that gain is only 2.5% higher than where you are at, do you still use it or do you actually have to hit a threshold that prompts a change? The issue here is that I thinks it's ridiculous to make a change unless you can show a 5% error minimum. Then you can set it wherever you want. I probably didn't word it well but meant 'from 25 to 30, 30 to 35. etc. If you have a 25% car that now shows 33%, go ahead and set it at 33% and document your new baseline...but don't reset a 25% car that shows 27%.

Or did I make that less clear that I originally typed it?
 
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JohnW8 said:
I was pissed off about this initially because of the randomness of it. If changes are made to the weight of the car why not wait until the end of the year or prior to the beginning of a new season? You know during the off season when people are working on their cars anyway.
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I will go on the record as saying I don't care when a change is made. If's its the right thing to do, its the right thing to do. We aren't a National class and we aren't racing for the gold medal so it's really no big deal. I would think that the 'other' cars in class would feel it's better to correct asap than wait.
 
Andy Bettencourt said:
I agree. But when that gain is only 2.5% higher than where you are at, do you still use it or do you actually have to hit a threshold that prompts a change? The issue here is that I thinks it's rediculous to make a change unless you can show a 5% error minimum. Then you can set it wherever you want.
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Ahh, I see your question. We never really codified an answer to that question, and so I don't know the answer.

My personal take is that (ack!) I agree with Mark Andy. At this point, the Miata is a perfect example of a car where we know a lot and we could credibly just go ahead and use the "known horsepower method", regardless of the difference from the existing classification. Remember that the use of that method requires the commitee's confidence in the dyno data to be quite high. If there's enough confidence in the dyno numbers, why not use it?
 
JoshS said:
Ahh, I see your question. We never really codified an answer to that question, and so I don't know the answer.

My personal take is that (ack!) I agree with Mark Andy. At this point, the Miata is a perfect example of a car where we know a lot and we could credibly just go ahead and use the "known horsepower method", regardless of the difference from the existing classification. Remember that the use of that method requires the commitee's confidence in the dyno data to be quite high. If there's enough confidence in the dyno numbers, why not use it?
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So I am with you again in theory. But are you suggesting that a 2-3whp difference from the original estimate is enough to make a change? You wouldn't adopt any minimum threshold? 1whp? 2whp? All these are ok? I think that is ridiculous and it sets a horrible precedent. Horrible.
 
JohnW8 said:
My original 92 miata 1.6 was listed at 116hp but on a dyno it peaked at 97hp.
I'll make the assumption that the 1.8's are the same. That car now has a 2001 VVt engine that is claimed to be in the 145hp range stock, but mine with I/H/E and ecu just barely makes 144 peak. So the claimed number and real numbers don't seem to be very accurate.
.
Click to expand...


I thought the 1.6 was 116 crank hp from the factory, while the dyno number you are mentioning should be wheel hp. I know my old CSP miata was just about 100 hp, and that was at the wheels.
 
JoshS said:
Ahh, I see your question. We never really codified an answer to that question, and so I don't know the answer.

My personal take is that (ack!) I agree with Mark Andy. At this point, the Miata is a perfect example of a car where we know a lot and we could credibly just go ahead and use the "known horsepower method", regardless of the difference from the existing classification. Remember that the use of that method requires the commitee's confidence in the dyno data to be quite high. If there's enough confidence in the dyno numbers, why not use it?
Click to expand...

Well, if they refused to accept the REAMS of info on the MR2 that showed a max of what 11-12%, and they used 25% as a factor, then I'd certainly think that similar evidence showing 2.5% should be viewed with similar skepticism.

I GET that this car is a concern because of the fact that it could be an overdog (although ITAC guys have stated that currently they don't think it is) and it demands vigelence, but, I also think that if you are going to accept evidence for one then you really have to for another.
 
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