June 2012 Fastrack

JeffYoung said:
For me, you are going to have to have rock solid 100% proof that a change in hp was due to something that is free in IT.

There is a lot of information out there on the 128 to 133 jump and in my mind it's not crystal clear. To you it is. We disagree. The Ops Manual allows us the flexbility to do that without one side screaming that the other is ignoring the rules.
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So what research did the committee do to validate the information? One call to Wheeler would have your answer. Or one call to Mazdaspeed.

This isn't open for interpretation here Jeff. It's fact. There is NO factory information out there that jump from 128 to 133 was due to anything other than ECU. The piston change was to bring the early motors up to the actual advertised CR, which it was below. All that is out there.

I'm done. Gets worse every time I open this thread. If any Mazda lurkers want to help validate this issue go ahead. Price is out there.
 
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Jeff -

It's reasonable to not believe *anything* on the internet. Instead call Tim Buck at Mazda Motorsports. Call Sam Henry at Springfield Dyno. Heck, call Jim Drago on the CRB/East Street Automotive. they can all tell you about the power being from the ECU.
 
Anyone ever pulled the restrictor plate off of a top level 94 1.8L Spec Miata on the dyno? How many HP is the RP robbing? I have seen a pretty good 94 1.8L pull low 120s on a dynojet(same dyno where good 1.6s are low 120s).

Kyle

EDIT: My SM buddy has pulled his RP on the dyno and says for him it was worth 4hp or so. That would put a good Spec miata built 1.8 motor at mid to high 120whp on a Dynojet.
 
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I'm really over the miata discussion. YES the CRB ASKED us to look at it. we decided that EVEN THOUGH the change was small, we should look at the higher HP, lower HP and Known HP numbers. we did. there was not confidence that the dyno plots were accurate and NOT leaving something on the table. so we went ahead and just ran it at the higher number, because that added 1 whp over the dyno plots and EVERYONE on the call that night signed off on it.

compromise, using the ops manual. with CRB involvement but NOT directing things.

the dam is holding.
 
Ok, I'll let it die. I have dealt enough with Chip and Jeff to know that I like them and trust them. I am so invested in the decision from EVERY angle that it's tough not to just keep responding to every rumor, thought process and procedure. I don't have to agree with it and that is fine.

As always, thanks to Jeff and Chip for staying on here and bashing these things out like Jake and I did when we were in their shoes.

As Lawton said today, 'I admire your persistence...got a new truck...can't wait for the NHMS race...bringing the family...let's pull up our panties and race!'

You got it.
 
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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**not about Miata** What happens when you are over 10% away from your classed percentage? Which in ITB is approximately 100lbs for every 5% I am halfway between 10 and 15 have to fight to get the car down form 30 to 25. A few months ago I put in more data to back up a letter. I hope that it is resolved soon.

It was my impression from talking to multiple members on the ITAC over the past few years I have been working to correct this error. That if "known hp" is used and you end up between two numbers you get rounded up. I am not going to stop developing my car. Heck my motor is a time bomb, that i built for the sole purpose of putting to bed what the motor car do in IT trim. Obviously there is always "something" that can be done to any build, but still counting pennies when we are off by dollars.
 
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Andy Bettencourt said:
As Lawton said today, 'I admire your persistence...got a new truck...can't wait for the NHMS race...bringing the family...let's pull up our panties and race!'

You got it.
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OK, you're paraphrasing just a little! :)


But it's true. Screw the 80lbs. I've got way more opportunity "fixing" the driver than I do worrying about 80lbs................. "Shut up and drive!!!" Let's go race!!!
 
quadzjr said:
**not about Miata** What happens when you are over 10% away from your classed percentage? Which in ITB is approximately 100lbs for every 5% I am halfway between 10 and 15 have to fight to get the car down form 30 to 25. A few months ago I put in more data to back up a letter. I hope that it is resolved soon.

It was my impression from talking to multiple members on the ITAC over the past few years I have been working to correct this error. That if "known hp" is used and you end up between two numbers you get rounded up. I am not going to stop developing my car. Heck my motor is a time bomb, that i built for the sole purpose of putting to bed what the motor car do in IT trim. Obviously there is always "something" that can be done to any build, but still counting pennies when we are off by dollars.
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So the MR2 is still in limbo. Tough to know where they are on that. It's a 3-4 year issue.

Now on what you describe, I am not sure it's been codified in the Ops manual but I can tell you from recollection what has been considered. When you use 'known hp' for a weight increase, you use the exact number to reset as the baseline. So lets say it's classed at 25% and it's proven to be about 32%. They would use a dyno number they were confident the car could achieve, back into a crank number and then multiply through. Typically, no change has been made when known numbers are within 5% of the current number but there is nothing codifying that either. We tried to at one point when I was there but we must have gotten derailed. It's amazingly time consuming to have to write down and lock in procedure for every little nuance of a thought process.

In the case of a weight reduction or 'proving a negative', they would look at the dyno sheets and then probably round up to the nearest 5% to allow for any further development. So in the case of the MR2, if they has a slew showing 11-13% gains, going from 25% to 15% would be an easy vote IMHO (actual number may vary).
 
Andy Bettencourt said:
So the MR2 is still in limbo. Tough to know where they are on that. It's a 3-4 year issue.

...
In the case of a weight reduction or 'proving a negative', they would look at the dyno sheets and then probably round up to the nearest 5% to allow for any further development. So in the case of the MR2, if they has a slew showing 11-13% gains, going from 25% to 15% would be an easy vote IMHO (actual number may vary).
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there are a PILE of letters on the MR2, basiclaly steven and the whole MARRS contingent have written in, and obviously it's an issue that I want addressed, too. the biggest problem lately is a shrinking ITAC memebrship, other issues that are "easier" jumping ahead in line, CRB interest changing the priorities further, etc...

there's also the "political" side of the thing, the car has a realistic floor weight of ~2300 lbs, give or take. 15% puts it at 2240, 20% at 2335, and 25% (current weight) at 2430. the dyno data we have is conclusive in proving the negative, but not in establishing the actual potential (based on expressed confidences and oppinions by members) so we will be picking a 5% step rather than working back from a "known" wheel number. 20% is still heavy, 15% is for all intents unachievable, even if "correct" per the above. some members have expressed difficulty with the idea of a 190# adjustment. no doubt the CRB will do a double take on it as well. setting an intermediate weight breaks from process and is a precedent we do not want to set, and adjusting to 20% still leaves the cars realisitially 35# above their actual minimum achievable weight AND 95+ over correct weight per process.

it's a PIA. and it's not getting the attention it needs.

if I were king, we'd class it at 15% and move on, but I do understand the other members' concerns, and I am biased. then again, if I were king, the process would be a lot more complicated and involve torque and stuff, becasue I'm not prone to developing simple solutions (though I try). The Process works REALLY well in ITA up to ITR (even with the disagreements between ops manual and established cars in R, and we are investigating). ITB and C see such HUGE weight swings for small changes in power that it leads a lot of overweight cars, some of which are still observably very fast on track. that on-track observation leads to foot dragging to make changes. cue viscious cycle.
 
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I gave up after 6 pages. :dead_horse:

I do have a question that concerns me a lot more than a weight add that WILL NOT slow the miata down in the least bit.

Why June 1? Why not wait till the off season. A weight change mid year seems outside IT Philosophy.
 
I would not Settle for 20%. That is way off the hp mark. I have built a fiarly stout motor utilizing everything possible within the rule set. A custom header built to burns mathmatics, a tuned ECU, super light oil. and I make what 2hp more than a guy with a bone stock motor, stock computer, with off the shelf header and intake. How much more capability do they think the motor has. Knowing what I have submitted to the ITAC I would really like for them to let me know the smoking gun that is going to net the huge gains that I have not implemented.

from a HP standpoint I am at 107.9hp (with crap for torque but another story and most within the IT community that I am aware of). Most guys of the IT guys are in the 103 to 106 range. as you can see the majority of the 4AGE IT community is running aroudn out there at 10% gains.

as a brief rundown for expected wheel hp for gain percentage.

10% 104.72
15% 109.48
20% 114.24
25% 119.00
30% 123.76

Remember the reason why the car needs an 190lb break is because it was classed with a multivalve 30% number that had nothing to do with the engine performance. If anybody has information stating what I have is false, skewed, or incorrect please let me know. If anybody on the ITAC has any information on ways to make more power (additional to the build sheet I submitted). I would be very interested. If you have a point of contact that I can talk to that has information to bridge the over 10whp gap I would also be very appreciated.

If there is no research or data on IT or similiar builds please make a decision just like you did for the miata. Give us a weight number to shoot for. It is true that the cars will have a very hard time, and the later cars if at all possible, to get down to 15% weight. Remember if you were to use the dyno plots the car would be classed at 13% weight. Adding weight to MR2 because of achieveable weights,is just putting the MR2 at another level still way off from being competitive.

Class the car at 15% (which we still have yet to achieve) and let us work to get the cars down to weight. Classing based on possible weight for the MR2 might not be the case for the other 4AGE powered cars (AE86, FX16)

The 4AGE powered community is growing very tired of being uncompeitive because of politics that is no fault of their own.
 
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spnkzss said:
Why June 1? Why not wait till the off season. A weight change mid year seems outside IT Philosophy.
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This was my biggest gripe. My car was already overweight... so what's a few more pounds. IF the ITA Miata argument has been going on for years then this change shouldn't have been a June 1st surprise. The need to now redo half of what I did in the off season is a PITA. (Engine #3 was the other half). I don't have scales or a trailer so I need to borrow both and burn another weekend or two to make this adjustment. I suppose the CRB has the right to make these rule changes but considering this is amateur racing it might be less painful if announcements like these are made during the off season. Either before the season begins, when most of us are working on our cars anyway, or after the season ends when changes are likely needed anyway. I like to get the car ready to go for the season (4-5 races) then only have oil changes and nut and bolt sessions between races because in the Spring and Summer, off weekends are hard to come by.
 
Andy Bettencourt said:
When you use 'known hp' for a weight increase, you use the exact number to reset as the baseline. So lets say it's classed at 25% and it's proven to be about 32%. They would use a dyno number they were confident the car could achieve, back into a crank number and then multiply through. Typically, no change has been made when known numbers are within 5% of the current number but there is nothing codifying that either. We tried to at one point when I was there but we must have gotten derailed. It's amazingly time consuming to have to write down and lock in procedure for every little nuance of a thought process.

In the case of a weight reduction or 'proving a negative', they would look at the dyno sheets and then probably round up to the nearest 5% to allow for any further development. So in the case of the MR2, if they has a slew showing 11-13% gains, going from 25% to 15% would be an easy vote IMHO (actual number may vary).
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Andy, you are still misleading the masses, unintentionally. Either you use stock horsepower and a gain (not based on dynos!), OR you use dyno power. If you are mentioning "percentage gain" *and* dyno power in the same breath, you are doing it wrong.

The reason for this is that if the dyno-based expected horsepower differs dramatically from the published-spec-based expected horsepower, it might not be the gain that was in error -- it might be the published spec. So you can't go futzing with the gain or comparing gains from one car to another.

So there should never be any "round up to the nearest 5%" discussion, ever. The Ops Manual makes this all pretty clear.

To remind everyone, to download the IT Ops Manual:
1) Go to scca.com
2) Log in to your account
3) Go to "Resources->File Cabinet"
4) Ops Manual link is under "Club Racing"
 
JoshS said:
So there should never be any "round up to the nearest 5%" discussion, ever. The Ops Manual makes this all pretty clear.

To remind everyone, to download the IT Ops Manual:
1) Go to scca.com
2) Log in to your account
3) Go to "Resources->File Cabinet"
4) Ops Manual link is under "Club Racing"
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If that is the case. ITAC. Do you want me to write another letter to classify the car at known power at 13%?
 
quadzjr said:
If that is the case. ITAC. Do you want me to write another letter to classify the car at known power at 13%?
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No, that wouldn't be the right approach. The right approach would be to ask them to use the "known horsepower" method and assign the weight based on the highest-available credible dyno horsepower.

Again ... you don't back into a multiplier based on dyno horsepower. If you are going to use dyno horsepower, you simply ignore stock power and multipliers, and just use the dyno power, converted to crank horsepower.
 
there is established precedent, though not explicit in the ops manual, to use a multiplier OTHER than 25% (or the "default" 30% ITB/C multivalve or as currently CRB imposed on V8s in ITR) when evidence shows the gain potential to be other but ACTUAL wheel hp to be unknown. S200s and other 4cyls in ITR are good examples.

in the case of the MR2, it's not all about proving HP any more (there are still doubters on comittee, and well, PK), it's the fact that dropping the car to 15% (based on above precedent and dyno data showing ~13% to be the max to date) means 190# publsihed min weight change from the current (25%) weight, or 285# since the change was made from 30% roughly a year ago. there's a feelign that even if that passed the membership sniff test (not everyone is aware of the details) that it would not pass CRB muster. I disagree with politically derived decisions when good mathematics exist, but there you go. fWIW, 108whp becomes 2210 lbs in ITB, assuming 15% driveline losses. functionally no different than a 15% classification as only a car driven by an 8 year old will get that light.
 
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I would hope that any use of actual wheel hp would rely on more than a single data point, or at least more than one dyno to generate numbers on that engine. I do not know anything about what data is or is not in front of the ITAC, but we do all know how easy it can be to tweak dyno numbers - whether via ecu tuning, tires/wheels, correction factors etc. Enough variables that can have an impact of significant weight in ITB and C that someone could honestly inadvertently submit flawed data (low or high).
 
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