SIR TEST RESULTS

OK, I need to finish the post I started with and did not complete. My reservations about there being a disparity between the bimmer and all others are based on the following. I run in GT2 with a 2280lb Nissan. I run against a Porsche GT3 Cup car at 2730. I ran this 05 with a stock 222hp engine. On the dyno, 204 RWHP. At Lime Rock we ran 57.3 and 57.7 respectively. He was faster. At LR you would expect us to be close. At Pocono 4 weeks later, as you would expect, he also was faster. But by a much larger margin as Pocono is basicly a double drag strip with an autocross course in the middle. He ran a 1.38.1 and I a 1.42.9. We went from .5 seconds apart to 4.8 seconds apart. Look at the numbers; 450 lbs - about 100 more RWHP - 4.8 seconds. Now the BMW 2850 - RX7 2680 are 170lbs apart. Say the BMW has 50 more HP. Do some extrapolation and the BMW should be about 3 seconds a lap faster than the RX7. But the RX7 has the lap record. Now I am assuming the same clockwise course configuration. A BMW with the driver sleeping should be able to best the RX7. Unless the other dynamic factors, such as air drag, rotational inertia about the about the mass centroid, ect... come into play. Now like I was saying, I do not see the smoking gun as others.
Chris Howard
 
Chris,

don't worry about a smoking gun or extrapolated track results.

Why can't the BMW race at the weight predicted by the ITS classing model as the other cars do?

All the other cars in ITS race at the calculated weight - witness the wholesale changes just handed down. The model put out 3150 or 3200 lbs for the BMW, so why would the BMW be expected to race at 2850 lbs?

Classing it incorrectly from the get go has resulted in this entire discussion.

Ron
 
Ron, I was hoping without me saying it, you would pickup on the model not being safisticated enough to do the job we are asking. IT comprises cars that are so all over the map physically that a simple HP/Weight formula will hang many out to dry. But as I have no horse in this race, You guys can have at it. Happy racing boys.
Chris Howard
 
Chris, you can not definitely say that the model is flawed based on single observations. Particularly an observation not even involving IT cars, and then another one based on no knowledge of prep level etc.

I could just as easily point to AARC results that show the BMW to be a shoe in winning car with obervations of the front running BMW sandbagging to save tires, etc. But that would be pointless.

Use the model. Class the cars. Make adjustments when needed. This has not been done or applied to the BMW because it has never raced at the model predicted weight and was known to be light when classed at 29XX.

R
 
Some good answers here. good to read them.

Mike, I think you are looking at things a bit skewed.

You just stated that you had a lot of fun racing your "modest prep" BMW against other guys and had a lot of fun. I'm sure you're not the only guy having fun in a modest prep car, but............you are in a small crowd, LOL.

Look at it this way. If things were fair, you would have been in a car that met process weight, and you would have had to prep the car just as your competition has to, to have had the same racing you had.

How would you feel if a guy came in under weight...and beat you?

So, you've had a few years having fun on a freebie....do you know how many other guys would kill for that? Be thankful for what you have.

So, some time in the sun, and not many have had that chance... I'd be thankful and accept the future.

(And yes, the timing sucks, and the CRB is well aware, and I hope and expect them to give fair notice of whatever choice they make, so just race what you have, and keep having fun.)
 
It's too late for me not to feel cheated. I don't know how to prep my car for this year; instead of having months between the rules settling down and my first race, I'm going to have weeks. Maybe.

That aside, I want to know that only the highly-prepared cars are affected. I had a two great seasons in a row; I ran neck-and-neck with a Datsun, and had a great time chasing around an E30 and an Integra. There was no disparity, no walkaways. I spent several races within one second of my competition.

Adding too much weight will take that away. Taking away too much air will take that away from me. And if lose the fun I've been having, I'll feel cheated.

So I'd like to see the SIR tests involve an E36 that isn't making these amazing horsepower numbers; anything over 200 hp seems quite incredible to me. What will it do to my modest setup? Andy, in berating those of us who "don't know anything about SIR technology" says that's exactly what will happen.

I'll believe it when I see it.
[/b]

Mike,
Since I'm in the same boat to a certain extent I can relate. I guess there is really nothing I can say, except any which way, we are going to lose something. This is a fact, if it's weight, A flat Plate Restrictor (FPR) or the SIR we will lose something. I wished I could tell you something different but that would probably be a lie. Depending on the extent of your engine build you will lose, as a example 10% (actual numbers not known). So the well built with a motect should rein supreme among the BMW's (from what I've been told). The SIR is the best solution so far, again, from what I was told. There are certain things some low budget to help you, like a adjustable fuel regulator and someone to burn you a good chip on a dyno, a decent set of headers and good tires. I would prefer a mediocare engine with a good suspension instead of the other way around. Driving well is the best way to get around the track faster.
I plan to test with and without the SIR so I can have options on where I can race. If the SIR doesn't work I can race else where until the ITAC & CRB get this right. I'm trying to remain optimistic and hope this works as well as they say it is going to. I'm being as honest as I can. I know what you are going through but it doesn't make it any easier.
dj
 
OK, I need to finish the post I started with and did not complete. My reservations about there being a disparity between the bimmer and all others are based on the following. I run in GT2 with a 2280lb Nissan. I run against a Porsche GT3 Cup car at 2730. I ran this 05 with a stock 222hp engine. On the dyno, 204 RWHP. At Lime Rock we ran 57.3 and 57.7 respectively. He was faster. At LR you would expect us to be close. At Pocono 4 weeks later, as you would expect, he also was faster. But by a much larger margin as Pocono is basicly a double drag strip with an autocross course in the middle. He ran a 1.38.1 and I a 1.42.9. We went from .5 seconds apart to 4.8 seconds apart. Look at the numbers; 450 lbs - about 100 more RWHP - 4.8 seconds. Now the BMW 2850 - RX7 2680 are 170lbs apart. Say the BMW has 50 more HP. Do some extrapolation and the BMW should be about 3 seconds a lap faster than the RX7. But the RX7 has the lap record. Now I am assuming the same clockwise course configuration. A BMW with the driver sleeping should be able to best the RX7. Unless the other dynamic factors, such as air drag, rotational inertia about the about the mass centroid, ect... come into play. Now like I was saying, I do not see the smoking gun as others.
Chris Howard [/b]

Chris,

The problem with your deductions is that you don't have all the information. On the weekend the record was set at Pocono - Kip VanSteenburg brought out his 944S for the 2nd time. Kip ran within .4 of the new record set that day, then has clutch problems and didn't run the next day. The RX-7 and the 944S were pretty dang equal considering the development work yet to be done on the Porsche...

The point? NO BMW's. From what I have seen (and this is a new track config - only 3 years old now) the BMW that BEAT this RX-7 at BOTH events in 2004 (and won the NARRC Championship that year) is at LEAST 15whp down on the top cars in the country. This is based on what is seen at RA vs. Pocono and the 8-10 car lengths they pull down south on the back side).

You have to know the facts in order to understand.

AB

Ron, I was hoping without me saying it, you would pickup on the model not being safisticated enough to do the job we are asking. IT comprises cars that are so all over the map physically that a simple HP/Weight formula will hang many out to dry.
Chris Howard [/b]

Chris,

As has been mentined on this site a bunch of times, there is no such 'simple' formula. The 'process' will never be perfect but it does take into account things like: aero, tranny ratios, suspension design, drivetrain layout, etc....and it is applied to all in the same manner.
 
Chris,

The point? NO BMW's. From what I have seen (and this is a new track config - only 3 years old now) the BMW that BEAT this RX-7 at BOTH events in 2004 (and won the NARRC Championship that year) is at LEAST 15whp down on the top cars in the country. This is based on what is seen at RA vs. Pocono and the 8-10 car lengths they pull down south on the back side).

You have to know the facts in order to understand.

AB


[/b]
Can you say with 100% confidence that it was at least 15hp as a fact? There are more factors than just hp. I think Chris makes many valid points. At some tracks horsepower makes a big difference and other tracks it isn't a big factor. A 100% driver with a 80% car can beat a 90% driver with a 100% car at this level. We should make this a claimer class like in karting.

I hope all of this works itself out for the best - so far it seems like a disaster. Time will tell.
 
Can you say with 100% confidence that it was at least 15hp as a fact? There are more factors than just hp. I think Chris makes many valid points. [/b]

Chris does make valid points. The issue at hand is that the 'process' takes those into account as best as possible. So the comments, while valid, were made without the understanding of the current methods (which have been posted here many times) So far so good.

You know I can't say 'as fact' on the 15whp. It was posted as my interpretation of actual results from first hand accounts and video I have watched. The only way we can tell 100% is if you post your dyno results from a dynojet....care to do so?
 
We should make this a claimer class like in karting.


So you think you should be able to steal someone elses hard work and developement when you get beat? Welcome to the mentality of persecution. Do your own work and catch up.
 
You know I can't say 'as fact' on the 15whp. It was posted as my interpretation of actual results from first hand accounts and video I have watched. The only way we can tell 100% is if you post your dyno results from a dynojet....care to do so?
[/b]

AB,
Guess who owns Rob's old car....................................me, but we'll never know since I blew the engine at MidOhio this past August. All his hard work ruined with a poor shift. I understand the car did well in 2004.

:lol:
Greg
 
AB,
Guess who owns Rob's old car....................................me, but we'll never know since I blew the engine at MidOhio this past August. All his hard work ruined with a poor shift. I understand the car did well in 2004.

:lol:
Greg [/b]

That's too bad. It was a real good car...but Rob can provide us with the number should he decide too. Am I wrong to assume that he provided them to a prospective buyer? Are you telling me that you don't know what it made?

AB
 
Mike,

Do you even read what you're typing? As Andy said, don't look for sympathy from too many people over this. You want a car that runs at the front w/o putting the time and money into developing both the car and the driver. Nobody else gets that kind of break. That's another reason that ALL cars should be treated the same.
[/b]
Do you even think about what other people have written before you fire off an acerbic response in return? Or are you so sure you have all the answers that you have nothing to learn from anyone else's opinon, and just go straight to the flaming?

What basis would you possibly have to assert that I haven't developed myself as a driver? That's as pompous and rude as it is wrong. Post like yours, focused on rhetoric and insults, lacking a desire to understand the point of view of others, are what make extracting real information from this forum so difficult.

Is it just that you're too ineloquent to express your opinion adequately that you have to resort to challenging my ability as a driver?

Back to the issue at hand: of course the BMWs aren't as prepared and are still competitive, and are overdogs when prepared to the limits (or beyond). They're more than twenty years newer than some of the cars they're running against. Twenty years! The Datsun guys I talk to aren't upset about spending time or money working on prep. They're more worried about getting parts to keep the things running in the first place. (Aside from the introduction of the 240Z, other memorable events of 1969 include the moon landing, the final public performance of the Beatles, and the Boeing 747 made its maiden voyage.)

Most of the E30's and Integras I race against aren't aggressively prepared, either. Sure enough, the ones that are beat me.

I think the classification problems the SCCA is having are caused by the lack of a plan to face progress. Newer models enter ITS every year. Those new models are, at a baseline, better prepared than the older cars in the class. This is going to keep happening—it's progress, and it is undeniable.

Successful organizations plan ahead to deal with progress. After all, it's forseeable that newer cars would out-perform older cars; that they'd have a higher performance potential, at least, and therefore be able to give closer to optimal results with less tweaking. Progress eventually includes abandoning the old and focusing on the new. If there are cars that are too slow to be in the class, let's move them to another class. Or move the newer cars to their own class where they can enjoy their competition without intefering with those who haven't moved on. Perhaps restricting modifications is a good idea; instead of an SIR, why not force the E36es to keep their stock air box?

Instead of hampering progress with weight penalties and intake restrictors, why not let the sport track progress?
 
I would prefer a mediocare engine with a good suspension instead of the other way around.[/b]

Thanks for your kind note, dj. I appreciate your honesty and sensible contributions to the forum.

Meanwhile, that's exactly where I'm at: I'm thrilled to pieces with my suspension, and my engine needs work. Perhaps, if my engine improves, then I'll end out out-driving my suspension. Or, maybe I'll move to a different class where I can concentrate on racing instead of rule changes.
 
Okay, I'll bite. It's the thread I started, after all.

It's too late for me not to feel cheated. I don't know how to prep my car for this year; instead of having months between the rules settling down and my first race, I'm going to have weeks. Maybe.

That aside, I want to know that only the highly-prepared cars are affected. I had a two great seasons in a row; I ran neck-and-neck with a Datsun, and had a great time chasing around an E30 and an Integra. There was no disparity, no walkaways. I spent several races within one second of my competition.

Adding too much weight will take that away. Taking away too much air will take that away from me. And if lose the fun I've been having, I'll feel cheated.

So I'd like to see the SIR tests involve an E36 that isn't making these amazing horsepower numbers; anything over 200 hp seems quite incredible to me. What will it do to my modest setup? Andy, in berating those of us who "don't know anything about SIR technology" says that's exactly what will happen.

I'll believe it when I see it.
[/b]


Mike,

Go through and read your post again. Just about every sentence has "I" in it. All you seem concerned about is how it impacts you, and how you have 'been cheated'. What about all those other drivers who's cars were marginalized by the mis-classification of an overdog in ITS? What about all those ITS drivers who were getting moved father down the grid by less than full-prep efforts (not unlike yours), and getting blown into the weeds by an all-out effort w/ a top driver?

Instead of wanting what's best for ITS in general, all you care about is what's good for Mike, and what will continue to let Mike have fun. You called my previous post ascerbic. Hardly. You also think it was rude that I suggest that you need to further develop the driver. Well Mike, I don't know too many people (some that have been racing for quite some time) that feel that there's no more to squeeze out of the nut behind the wheel. But, I'm not surprised at your attitude, given the selfish nature of the post I quoted above. You want a humbling experience? Put a known hot shoe in your car and see how many seconds a lap faster than you they are. If two years in Regional Club Racing makes you a fully developed driver, then you might want to check your messages, I think Roger Penske is trying to get in touch w/ you.

Instead of hampering progress with weight penalties and intake restrictors, why not let the sport track progress?[/b]

Just wanted to comment on this one. First off, if the E36 gets lead, it's not a 'weight penalty', it's because the published spec weight was incorrect. As others have pointed out in other threads, we haven't heard any of the drivers of the other cars that got weight complain about a 'weight penalty'. The E36 should weigh ~3150#, based on the results of the same process that all other IT cars get put through. The fact that the CRB is looking to find an alternate way to make the car fit the class, is a GIFT. It's the responses from people like you that make me think that the better alternative is to declassify the car.
 
Back to the issue at hand: of course the BMWs aren't as prepared and are still competitive, and are overdogs when prepared to the limits (or beyond). They're more than twenty years newer than some of the cars they're running against. Twenty years! The Datsun guys I talk to aren't upset about spending time or money working on prep. They're more worried about getting parts to keep the things running in the first place. (Aside from the introduction of the 240Z, other memorable events of 1969 include the moon landing, the final public performance of the Beatles, and the Boeing 747 made its maiden voyage.)

Most of the E30's and Integras I race against aren't aggressively prepared, either. Sure enough, the ones that are beat me.



[/b]
Mike, I am not sre which 240Z guys you are talking to but since I build engines for about every 240 in the PNW I think you are wrong. I don't know of a single one that isn't tired of seeing marginally prepared BMW's kicking their butts. The fact that 240z's are 35 years old doesn't make them a bad car and I don't understand your elitist attitude toward them. If a class is properly balanced there is no reason that multiple marques shouldn't competitive. You have admitted to having a wrecking yard bottom end and a fresh head with a stock exhaust manifold on your ride. You are beating cars that have 5 to 8 k in an engine every 2nd year. These cars have 2500 dollar exhaust system and run 800 bucks worth of new tires every other weekend to keep up with your underdeveloped BMW that if I remember correct is running on toyo tires and likely getting 4 to 5 weekendds out of them. This adjustment was not done because Mike B. owns a BMW, it was done tobring balance back to one of the best classes in SCCA. You are lucky in the fact that since you race with ICSCC and you can always just run your car in CP or DP and not change a thing.
 
The reason you are having a hard time with it is you are essentially trying to compare indivdual data points. Forget the track data for the moment.[/b]

Indeed. If track data were driving this (no pun intended), then it would most definitely be a comp adjustment. But track data isn't driving this. In fact, this isn't an isolated adjustment. It's simply part of reworking the classification of virtually every car in the ITCS. Some went up. Some went down. Some stayed the same. And one is in limbo.

When the ITAC uses the forumla used to class ALL the cars in ITS it spits out a weight. Every other car in ITS got that weight assigned and a lot of cars got adjustments up or down. Except the BMW. The weight spit out for it was 3150 or 3200 lbs.

Now, all the other cars in ITS use the assigned weight, why not the BMW?

I, nor the others, can help the car was classed too light to begin with. Now the adjustment seems excessive, but it wouldn't seem excessive if the car was closer to the target, like it used to be, at 29XX lbs. [/b]

And to put this into perspective.....

For those who don't like the idea of the E36 having to weigh 300 lbs more or have to use an SIR, imagine now how the rest of the field felt when the E36 was classified 300 lbs too light! I'm not trying to stir up trouble. But just think about how that is received. A new car comes into the class is 300 lbs too light!
 
Well, Geo, a bunch of guys thought, "Holy helium Batman, I bet the E36 can ROCK at that weight! Lets get one before they smarten up and change it!"....
 
Jake - I was very close to buying an E36 recognizing how dominant it was. Ended up going SPO. No haggling over rules in that class.

I did a test and I drove my Mazda and then a average built BMW. My RX7 is a top car at every level. The bimmer was just a better car - newer, more modern but the motor is just awesome.

I still have my RX7 though and I'll drag her out every now and then to mess with my ITS pals. :D
 
The bimmer was just a better car - newer, more modern but the motor is just awesome.
[/b]
Those damn Germans sure can build a car! B)
It's a shame that the SCCA likes the rice burners & GM better, look at today's T1 and yester year when the Audi's dominated Trans AM. But IMSA did the same to the Audi's after a few years. :rolleyes:
 
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