IS300 in ITS?
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Andy Bettencourt
Super Moderator
Roughly 210whp or 250 crank is what I use when the topic comes up. Based on those numbers (which have been verified by multiple sources), to fit into the current make-up of ITS, the E36 325 SHOULD weigh in excess of 3200lbs WITHOUT a restrictor. Couch that with the 172hp E46 at 3000lbs (which nobody seems to be unhappy with), the 189hp car SHOULD weigh a couple hundo more, no?
Some have commented that 200+ lbs of ballat is excessive. While I agree to a certain extent, properly done it should be no issue. Our team RX-7's run 100lbs on the floor and full 14 gallon gas tanks at the start of every 30 minute sprint. That's about 160lbs right there...
AB
lateapex911
Super Moderator
Ignored?
IGNORED?????
Sorry, no dice. I have responded to many of the E36s camps posts and ascertations. So has Darin and Andy, all on the ITAC.
But what I see is a certain denial of the situation, with spin and misleading data sets. Quoting results is not exactly focusing on the mechanical properties of the car.
The one dyno number mentioned, 195, is fine, but doesn't match other numbers submitted previously. Good to add to the data points.
We've discussed the numbers a few times, Darin has outlined the process, and we've even asked for your opinions on options.....I can't remember a time that there has been a more open process, nor a time when there was more open communications between the commitees and the racers. It is truly unprecedented.
I suggest it would be wise to utilize it.
IGNORED?????
Sorry, no dice. I have responded to many of the E36s camps posts and ascertations. So has Darin and Andy, all on the ITAC.
But what I see is a certain denial of the situation, with spin and misleading data sets. Quoting results is not exactly focusing on the mechanical properties of the car.
The one dyno number mentioned, 195, is fine, but doesn't match other numbers submitted previously. Good to add to the data points.
We've discussed the numbers a few times, Darin has outlined the process, and we've even asked for your opinions on options.....I can't remember a time that there has been a more open process, nor a time when there was more open communications between the commitees and the racers. It is truly unprecedented.
I suggest it would be wise to utilize it.
What better thread for a newbie to make his first post in? :119:
There are hundreds of BMWCCA guys who would love to know how to get 220rwhp out of an M50 without cams. If one takes the "best" theoretical driveline loss at peak HP thrown out there (15%) that's 255HP at the flywheel at the peak...notably above the magic 100HP/L mark that BMW enthusiasts have long sought. In reality, the S50 (3.0 motor from the E36 M3) makes just barely more than that on a good day. Further, real world testing has shown the e36's fall into a band of 17%-20% loss at peak, including much newer models like the E46 M3. While we've been offered a real world dyno showing significantly less, we have not been offered one showing 220. Why is that?
Perhaps the most telling aspect of this thread is that LBS/HP seems to be the sole factor for consideration amongst a certain crowd here. There has been scant mention of the performance impact of increased weight on an identical width wheel/tire combination. Why is that? Is it because the lighter competitors know that it is not in their competitive interest to broach the subject? Or is the assumption that running an extra couple hundred pounds on the same tire sizes is not disadvantageous already? What of braking distances and cornering speeds? These are unaffected by HP in the main yet are brutally penalized by weight increases. This isn't drag racing, right?
As someone currently on the cusp of building an ITS car (or should I say presipice?) this thread sure makes SRF awfully appealing.
There are hundreds of BMWCCA guys who would love to know how to get 220rwhp out of an M50 without cams. If one takes the "best" theoretical driveline loss at peak HP thrown out there (15%) that's 255HP at the flywheel at the peak...notably above the magic 100HP/L mark that BMW enthusiasts have long sought. In reality, the S50 (3.0 motor from the E36 M3) makes just barely more than that on a good day. Further, real world testing has shown the e36's fall into a band of 17%-20% loss at peak, including much newer models like the E46 M3. While we've been offered a real world dyno showing significantly less, we have not been offered one showing 220. Why is that?
Perhaps the most telling aspect of this thread is that LBS/HP seems to be the sole factor for consideration amongst a certain crowd here. There has been scant mention of the performance impact of increased weight on an identical width wheel/tire combination. Why is that? Is it because the lighter competitors know that it is not in their competitive interest to broach the subject? Or is the assumption that running an extra couple hundred pounds on the same tire sizes is not disadvantageous already? What of braking distances and cornering speeds? These are unaffected by HP in the main yet are brutally penalized by weight increases. This isn't drag racing, right?
As someone currently on the cusp of building an ITS car (or should I say presipice?) this thread sure makes SRF awfully appealing.
Banzai240
New member
Are you KIDDING ME??? How many times do I have to mention that BRAKES, TRANNY RATIOS, SUSPENSION TYPES, ETC., ALLLLLLLLL come into play when making a classification spec recomendation?? This post has lasted for 10..... TEN pages and I'll bet I've had to re-iterate this point at least once per page...
Once again... wt/pwr is used to determine the BASE SPEC WEIGHT... After that is determined, we can then decide if that weight can be realistically reached... If Yes, then we have the right class... After that, We look at specifics and use "Adders" to the weight (+/- weight) to compensate for vehicle specifics...
I just don't know HOW much simpler, or fair this could be...
As for getting ready to build an ITS car... I just don't know WHAT would be stopping you??? The past two seasons have been some of the most exciting in IT, and most of the ITAC believes they are just going to get better... We have more cars classified, newer cars classified, we've moved some traditional underdogs, ITC is gaining some momentum... AND, we finally have a mechanism to fix mistakes when we make them, and possibly to fix mistakes of the past... Everything is happing according to plan...
Hell, competition is already getting tighter, and people seem to be excited...
It's up to you, but if you want to miss out on all this, it's your loss... I'm betting, however, that you aren't going to be able to resist!
(and... SRF??? :119: Hey, if you want to go run around the track in a non-descript car, competing with a bunch of other non-decript cars... all of you with exactly the same equipment, and all running the same lap times... well... maybe I should just keep my thoughts on that to myself...
Banzai240
New member
That's easy... we use all of them we can get our hands on... and, we'll compare that to estimates... and, we'll come here and ask you guys... and we'll talk to any experts we may have available... and we'll look at other cars with similiar drivetrains... and ....
We gather all the information we can get, then we make the best decision we can based on that data...
If no data is available, like with a new classification, we use the estimation process that I've been describing for many pages now to come up with what the performance potential is for a car... to date, I doubt we have been off by more than 5hp or so, but even that can make a 50 or 75lbs difference in the final weight...
It's not easy, nor extremely concise, but if we can be consistant, then no ONE car get's treated any differently than the others, and, on average, we should get most very close...
Try it sometime, guys... Let's us know how easy you think it is to get the specs set to the degree of accuracy you guys think it should be, keeping in mind that, for every ONE HP you are off, you could be adding or subtracting a substantial amount of weight from the specs...
Andy Bettencourt
Super Moderator
Why doesn't anyone use their real name or provide a proper signature anymore?
We have been provided dyno sheets that show 195. *I* have seen a 215 number on a dynojet for a top 3 ARRC car. I have had people verify 210 all day. Why does nobody jump up and waive their 210whp sheets around? Let's not have to go into the obvious.
Lbs. per hp is NOT the sole factor. I am not sure how many posts you are not reading in this thread but it can't be stated more clearly. It is used as a FOUNDATION for a subjective process that take into account many factors. MANY FACTORS.
Ahhh, the performance issues with increased weight. We understand. We won't be able to balnce our results on a pin-head, but we understand that these things are not linear.
Bottom line for the Bimmer guys? Apples to apples, is there a car that can compete with the E36? Other than the Mercedes (which I REALLY think got classed without REALLY knowing what it was), I submit no - and it's a resounding no. And when you compound the cost of a car like this...many people think it is ruining ITS in some parts of the country.
I have received soooo many PM's during this thread from people who really feel like the BMW guys are more worried about their performance advantages going away than they are about good racing and class equity.
Call up Chet and Larry. Have them post their numbers. James Clay can come on here and publically make a statement, he has before (in a vague way), and they support our numbers.
Competitivness is not guaranteed...but I tell you what, the better of IT is my main priority.
AB
We have been provided dyno sheets that show 195. *I* have seen a 215 number on a dynojet for a top 3 ARRC car. I have had people verify 210 all day. Why does nobody jump up and waive their 210whp sheets around? Let's not have to go into the obvious.
Lbs. per hp is NOT the sole factor. I am not sure how many posts you are not reading in this thread but it can't be stated more clearly. It is used as a FOUNDATION for a subjective process that take into account many factors. MANY FACTORS.
Ahhh, the performance issues with increased weight. We understand. We won't be able to balnce our results on a pin-head, but we understand that these things are not linear.
Bottom line for the Bimmer guys? Apples to apples, is there a car that can compete with the E36? Other than the Mercedes (which I REALLY think got classed without REALLY knowing what it was), I submit no - and it's a resounding no. And when you compound the cost of a car like this...many people think it is ruining ITS in some parts of the country.
I have received soooo many PM's during this thread from people who really feel like the BMW guys are more worried about their performance advantages going away than they are about good racing and class equity.
Call up Chet and Larry. Have them post their numbers. James Clay can come on here and publically make a statement, he has before (in a vague way), and they support our numbers.
Competitivness is not guaranteed...but I tell you what, the better of IT is my main priority.
AB
No joke. I have read all 10 pages of this thread with the required breaks to wiped my glazed eyes. 10 pages of "the 325 is too light compared to it's curb weight" and "the 325 is too light for the HP it makes in IT trim" is what I see. There was one reply - and only one - that expressed any concern about the effect of additional weight on tire performance. There are dozens, however, that refer to mythical horsepower numbers that are, on one bmw email list, described by bmw racers as being proponed by people "smoking crack".
Further, as you clearly point out in your second reply to my post, 1hp this way or that can make a multiple pound difference. As such, pointing out the difference between 210 and 220 is as important as it is valid. Thank you for helping me to make my point.
In pointing out that the 325 is significantly heavier to begin with I had hoped to highlight that the effect of weight is not linear with respect to performance. The numerous arguments posted here that the 325 is light strictly with respect to curb weight or potential horespower output (whatever it may be) is overly simplistic and ignores significant effects in performance areas other than straight line acceleration. To put a fine point on it, as one of the heavier cars in the class while running on the same tire sizes, it is appropriate that the car be some amount under the "program target" percentage of curb weight.
The cognitive dissonance involved in bashing SRF for all running the same lap times (last SRF race I watched this was not the case, btw) while complaining that the dissimilar cars in ITS are not running the same lap times is...well, Andy Bettencourt was right and we shouldn't delve into the obvious.
As for my looking at SRF: Have you driven one? I have and they're actually a very exciting ride and, despite being very low on horsepower, quite a rush even compared to my E46 M3 race car. And those similar lap times...yeah, close racing sounds really boring, eh?
Andy,
My name is Dave Dillehay. I live just south of Houston, TX. I choose to register as "DoubleD" for two reasons: 1) There is no reason that you or a vast majority of the users on this message board would recognize my name and 2) I am much more recognizable within the BMW internet community as "DoubleD".
DoubleD was a nickname given me because of my initials and fondness for the female form. I had no intention of hiding my identity and, although you could not have known, was in fact revealing it to many by using that name. I have added my name to my signature.
As for the meat of your reply....
First off I'd like to remove James Clay from this discussion. James is someone I consider a friend although we've never met face to face. Asking him to pony up a number is a great disservice to him. That he was vauge in the past is a credit to him. Please keep in mind that he has both business and competitive interests involved in that issue, both of which involve significant sums of money. James could only be hurt by posting a single number, regardless of it being high or low of your expectation.
Second, with respect to your assertion that nobody complains about the weight of a 323, I must take exception. Although I would very much prefer to build an ITS E46 chassis, at 3000 pounds it is a non-starter. That weight on 7 inch wheels strikes me as simply preposterous. I've raced a 3280lbs car on 9.5" wheels and 275mm tires and found that, even in short 30 minute sprints, tire conservation is a significant limiting issue. Trading 10% of the weight for 20% of the tire sounds like a nightmare in reccuring rubber expenditures.
Third, I've long ago learned that I can often come across rather acid in text. I'd like you to know that this post, along with my first, is not intended to be acid...I simply refuse to write a second draft. It is my intent to respectfully yet forcefully express my concerns about over penalizing the BMW's for success. Perhaps ITAC might do well do learn from SWC GT. If 325's get to the 3000lbs mark they'd be few and far between as nobody in their right mind would cut the $7,000 check for an ITS BMW motor that couldn't possibly win.
Banzai240
New member
First off, "Significantly heavier"??? THAN WHAT??? There are ALL KINDS of ITS cars that are in the 2650-3000 range... a couple even more... and NONE of them have the power that this car does... whether it's theoretical or otherwise... I haven't seen ONE number thrown out here to this point that would support it being at 2850lbs...
Your obviously not clearly getting the message here, so let's cut to the chase... NOTHING is being done in an "overly simplistic" way... all factors than can be reasonably dealt with are being taken into consideration... EVERY car is being looked with the same process... therefore, every car is getting equivalent consideration... Additionally, believe it or not, there ARE others out here who are capable of reasoning that adding weight will affect various aspects of performance... BUT, that's the idea... When a car pulls everyone by 6-7 car lengths everytime it enters a straight, and can still brake deep and get through the corner, more than one aspect of it's performance NEEDs to be considered... (6-7 car length story brought to you by some insiders in the CA area who whitnessed said events...)
However, if you'd like to donate the computers, and the F1 engineering team to run them, in order to consider all the factors you think are necessary to get these cars equivalent, then we'd be happy to accept the help...
To say that the car is "right" at 2850 is seriously ignoring any reasonable amount of significant facts on the matter...
Z3_GoCar
New member
I guess there are two ways to take this. Basicly, I'd assume he means that he wants a better restrictor and keep the weight the same and that has been sugested. The only team that a better restrictor will hurt is the team that spends 10-20k (obviously over exaggerated) on their engine development. If cams are being swindled in to get those kind of hp numbers, then this will render them ineffective. If your car's not developed to the point that it's bumping on all it's potential, the restrictor won't do a thing. Don't get me wrong, I'm interested in building a bimmer too, just not a 325. My main reason for enter this thread was to point out that there's an e36 that's speced at 2840 lbs and would be lucky to make 170hp at the crank with the same drive tran, but I've said enough. Just build your car and have fun, and who knows maybe you'll
James
lateapex911
Super Moderator
But James, he didn't say that. He said the car would be too heavy for it's tires.
I have to read what people write, not what they might mean, as much sense as that might make, LOL....
lateapex911
Super Moderator
Well, maybe it's because guys in the know feel they'd be selling out their BMW buddies by spilling the beans.
Here are a few examples that I am aware of (numbers related to me or another ITAC member but on the grounds of secrecy):
-A former ARRC top runner, related his HP results, and his discussions of those numbers and potential for growth of those numbers with a top BMW builder.
- A witness to dyno runs of some top cars, also top ARRC runners.
Of course, I can't divulge the source, nor the numbers as I have been asked to keep the details private, but they are FAR north of 195.
If you'd like I can go back and quote myself, but I would rather not waste the time unless you need me to. let me know.
The basic point of my earlier comment relative to this was that indeed, any "adders" would be tempered by the fact that the car would be operating at a weight that was getting out of the linear range of the tires response curve, and that factor would be considered. As a member of the ITAC, I can assure you it HAS been mentioned, and it WILL be mentioned again if the subject comes up.
However, lbs /hp IS a significant factor in the "raceability" of any car. And it needs to be close to have good fair racing. But again, it is only a part of the equation.....
Look, from my point of view, and for the gazilllionth time, I want the cars to cross the line in a dead heat, their physical properties equalized, with the difference between cars coming down to prep and drivers. PERIOD!!!
As it stands now I get the feeling that the BMW guys are feeling that their superior tuning and prep work is getting penalized. That is not the case, as the car is superior right out of the box over many, and has a leg up on most after moderate development. I remember a quote from a BMW driver when the restrictor plate issue came up where he expressed dismay that he would have to "actually fully develop" the car to stay at the front.
Sadly, he didn't include an address so that a box of tissues could be sent.
Ron Earp
Administrator
Well, you are attracted to the BMW for a reason. And, it would seem that the reason you, and many others I might add, are attracted to it is because it is winning consistantly.
It is winning because it is a total package - good suspension, great brakes, and great motor. Clearly, the car now exceeds the ITS envelope for cars and has become the "car to have", which I submit, is why you are looking at it. And, it is natural for you and others to get defensive when talk abounds of reigning the car in line with the rest of the ITS cars.
Some folks are complaining about weight, others are complaining about having a restrictor. But what else can be done? Force you to run 10" solid disc rotors with some rear drums like I have to use? That'd certainly slow you down.
So, a restrictor or weight makes sense to alter the performance of the car. There are other cars classed at a higher weight in ITS. If the BMW gets a higher weight then tire and brake costs may rise a bit - but the ITAC doesn't guarentee that your car of choice will be competitive nor do they guarentee that your choice will be cheap to run.
Anyone denying that the car is a overdog simply hasn't been passed by a top running BMW, and it might be possible you don't have a top running BMW in your run area. It really doesn't matter how much rear wheel hp it makes - just come down to VIR and watch the top BMWs run away from the field, then, watch them slow down many seconds per lap once comfortably ahead. Watch it happen not just once, but month after month.
This whole thread started because someone asked about an IS300. A car that is identical to the BMW 3 series (at least Toyota thought so). As soon as it was mentioned it immediately drew fire because the 3 series at its current classifcation is an overdog and everyone knows it. To argue otherwise simply means you drive one and don't want any changes or you are ignoring reality.
Bill Miller
New member
Dave,
First off, to compare BMWCCA prep levels to a top SCCA ITS E36 prep level, is just not valid. The organizations are different, the drivers are different, the competition level is different, and the prep level is different. So, let's not state the obvious.
Now, let's talk about those HP numbers. We have a person that's posted a RWHP number of 195, from a car, by his own admission, is not a maxed-out development effort. Using your 17-20% driveline loss, that's between 235 and 245 at the crank. Add say 7-10 hp for some additional development, and it's easy to get to tbe North side of 250 HP at the flywheel. But, as has been stated several times, peak hp is not the important number, it's the area under the hp and torque curves. Start comparing those, and see what that shows. Also, I believe Andy, Darin, and Jake have all stated that even at 195 RWHP, the car is too light, based on the process. Knowing that there was HP left on the table w/ that car, only means that the cars are that much more underweight.
As far as why no one's offered up the dyno sheets on a maxed-out effort, that should be pretty obvious. The way it would hurt, is because the true potential of the car would be known, and it would only further reinforce that the car was too light. If there was no way the cars could get lead added, I think you'd see a lot more published data. It would be used for marketing purposes. If James Clay could squeeze 3-5 more HP out of the car, than any of his competitors, don't you think he'd promote that fact? The reason that the folks in the know, aren't posting up the data, is because they know the truth, the car is way under weight for ITS. Me personally, I'd like to see ITR added above ITS. Cut the weight of the E36 to 2700# (maybe 2600#), and move it up to ITR. Throw some other cars in there, like the IS-300 mentioned in the thread title, the 2.7 and 3.0 liter 911s, E30 M3 (hell, even the E36 M3), C280 M-B, etc., etc., etc. and let them have at it.
The real issue here is, a bunch of folks picked an overdog car, and like being able to run up front, either w/o a maxed-out development effort, or w/ less than top-notch driving skills.
And if you're worried about tire/brake wear, the answer is simple, don't over-drive the car. There are plenty of cars in ITB/C that are on the North side of 2700#, that have to run on 6" wheels. They seem to get by. And you've got plenty of examples where there is almost 1000# weight difference between some of the cars.
I'm attracted to the BMW because it's what I know. I know where to get a donor car, parts, possibly a little sponsorship, etc. I'd also have a chance to race it 6 or more times per year without towing all over creation which is a major consideration for me. And yes, I want to build a car that will provide me an opportunity to win a couple seasons down the road. I guess wanting to build a car that has a good shot at winning makes me unique in SCCA.
I'm not saying that the car isn't an overdog in the class. I'm saying that adding hundreds of pounds to the car (and someone has mentioned 3200lbs!) will make it a complete dog. I can see that is exactly what some folks want though.
Catch22
New member
And maybe that Integra is cheating?
Or maybe those are Slow BMWs?
Whats the ITS record at Summit?
Thats the important question. Not "Who beat whom" on a given day.
The type of dyno is unimportant as they are all different. Then throw in weather conditions, calibrations, operators... And you have a crap shoot.
What is important and useful is comparing cars from the same dyno, preferably the same day and even time of day. When you see me comparing cars, thats what I'm doing.
You will never see me compare numbers from an Integra on a Mustang Dyno in February to a BMW on a Dynojet in July. Thats just stupid.
I've heard of ITA CRXs that get "Over 130whp" on a dyno down in Florida. Then they come to Road Atlanta and get waxed by other ITA CRXs that get "about 120" on a dyno in Atlanta.
So pick a dyno, any dyno. Doesn't matter. Jast make sure that when you compare cars its from that same dyno.
Or maybe those are Slow BMWs?
Whats the ITS record at Summit?
Thats the important question. Not "Who beat whom" on a given day.
The type of dyno is unimportant as they are all different. Then throw in weather conditions, calibrations, operators... And you have a crap shoot.
What is important and useful is comparing cars from the same dyno, preferably the same day and even time of day. When you see me comparing cars, thats what I'm doing.
You will never see me compare numbers from an Integra on a Mustang Dyno in February to a BMW on a Dynojet in July. Thats just stupid.
I've heard of ITA CRXs that get "Over 130whp" on a dyno down in Florida. Then they come to Road Atlanta and get waxed by other ITA CRXs that get "about 120" on a dyno in Atlanta.
So pick a dyno, any dyno. Doesn't matter. Jast make sure that when you compare cars its from that same dyno.
Not exagerated at all! Give Sunbelt a call and ask him what the price of a complete ITS motor is. The range is $7,000 to $13,000. Add to that 3K in intake and exhaust components as a minimum. Engine management can easily cost another 3K. It is impossible to build a fully developed E36 325 engine package for under 13 and it's easy to spend 20.
Bill,
I'm not trying to compare the prep levels. You're right that the organizations are significantly different. I'm pointing out that people who eat, sleep, and dream BMW engines know that the numbers being tossed around simply aren't happening. Please note that I have not claimed that 195rwhp is the max you're going to see...only that 220 is a pipe dream...or some good marketing.
There's another reason that numbers may not be provided. Perhaps they are not as big as people think and the builders don't want to publish that their engines don't make as much power as people think the other guy's does. Publishing a number like that would be somewhat detrimental to business, don't you think? Further, what advantage is there for an owner to let his competitors know what they need to shoot for? It is racing after all.
I will say this unequivocally: Secret numbers witnessed by secret ITAC members one time on one car on one dyno on one day is not my idea of a firm basis upon which to write, or in this casse rewrite, rules.
-DD