ITS e36 BMW

[JeffYoung]

Error on my end on the multiplier. Your number is right.

[JeffYoung]

Appropriate weights for a RWD ITS car with no other adders at the following WHP:


170: 2675
180: 2830
190: 2990
200: 3146
210: 3305
220: 3460
230: 3620

AND -- Andy has exposed the latent lurking "problem" in ITS, which remains fairly well balanced. The class multiplier is too low.

Z cars make 170-175 whp. They were never expected to. Race weight is 2430 to 2460 (I think), not 2675.

Miata is at 160ish. Never expected that. Race weight is 23xx not 25xx.

My car? 180ish whp. RX7s, same. Sould be in the 2900 range, not 2680 and 2560 (I race at 2710 right now).

And so on.

We've been lucky that all cars have developed upward in unison but the numbers are way off what actual rwhp figures would generate.

[Andy Bettencourt]

So if you brought the multiplier from 12.9 to 12.25 you would get this:


170: 2675 --------> 2540
180: 2830 --------> 2670
190: 2990 --------> 2840
200: 3146 --------> 2990
210: 3305 --------> 3135*
220: 3460 --------> 3285*
230: 3620 --------> 3435*

* I submit there should be nothing in ITS making 210whp+

[JeffYoung]

So if you brought the multiplier from 12.9 to 12.25 you would get this:


170: 2675 --------> 2540
180: 2830 --------> 2670
190: 2990 --------> 2840
200: 3146 --------> 2990
210: 3305 --------> 3135*
220: 3460 --------> 3285*
230: 3620 --------> 3435*

* I submit there should be nothing in ITS making 210whp+

Correct, those cars should go into ITR.

That sure looks a lot more like "reality" above.

[Greg Amy]

* I submit there should be nothing in ITS making 210whp+

Correct, those cars should go into ITR.

In which case, the discussion of the E36 325 in ITS is a moot point. Kill the SIR-equipped E36 from ITS.

GA

On edit: if we'd had ITR back then, that would have never happened in the first place. This is one of the car's that begat ITR's genesis...make it go away.

[Andy Bettencourt]

That sure looks a lot more like "reality" above.

Make it so number 1.

[JeffYoung]

In which case, the discussion of the E36 325 in ITS is a moot point. Kill the SIR-equipped E36 from ITS.

GA

On edit: if we'd had ITR back then, that would have never happened in the first place. This is one of the car's that begat ITR's genesis...make it go away.

Agree 100%. SIR has no place in IT.

[chuck baader]

OK, when the SIR was added, the e36 was a gross overedog. Since then, several cars have been developed to equal or exceed the original e36 so must we revisit the whole group (ITS) to once again establish parity? The SIR has been around 5-6ish years and it has taken the group that long to catch up? And that means those who want to compete with the car must rely on 5-6ish year old rules to limit their performance?

And what Jake said is how I remember the discussion going forth. Most just gave up!! Other things I heard were that the SIR either killed the power below competitive levels, or people blew motors....and that is not a cheap motor to rebuild!!

Another point, the e46 323. Same motor, but with double vanos, 3000#, same brakes, better aeor....yes the car to build at this point.

[JeffYoung]

OK, when the SIR was added, the e36 was a gross overedog. Since then, several cars have been developed to equal or exceed the original e36 so must we revisit the whole group (ITS) to once again establish parity? The SIR has been around 5-6ish years and it has taken the group that long to catch up? And that means those who want to compete with the car must rely on 5-6ish year old rules to limit their performance?

And what Jake said is how I remember the discussion going forth. Most just gave up!! Other things I heard were that the SIR either killed the power below competitive levels, or people blew motors....and that is not a cheap motor to rebuild!!

Another point, the e46 323. Same motor, but with double vanos, 3000#, same brakes, better aeor....yes the car to build at this point.

What is it exactly that you are asking for?

[Greg Amy]

Rules really haven't changed since then. But we now have better shocks (at lower prices), better cages (designs are a lot more clever), better engine management (open ECU and sensors), and - most importantly - better tires since the early aught's (anyone want to go back to RS3s? Didn't think so.) Just imagine what a fully-built and continued-to-be-developed E36 would be like today, had not everyone "gave up" (or went to ITR) because of the SIR.

As I noted above, the CRB tossed in the SIR to reign in that car, as an alternative to simply telling it to go away. Trust me, the latter was a definite consideration (that or ~500 pounds). And that got us all to talking about a class faster than ITS in order to bring in all these cars that had no other place to go. Voila: ITR.

There's a couple of seriously-developed and well-driven ITS E46 323 up here in New England, built and campaigned by one of the groups that used to campaign the E36 325is in the bad old days (Autotechnic). And they are doing quite well... - GA

[chuck baader]

Either revisit the great revision on the e36 or classify it the same as the e46 323, at 3000#

[Andy Bettencourt]

OK, when the SIR was added, the e36 was a gross overedog. Since then, several cars have been developed to equal or exceed the original e36 so must we revisit the whole group (ITS) to once again establish parity? The SIR has been around 5-6ish years and it has taken the group that long to catch up? And that means those who want to compete with the car must rely on 5-6ish year old rules to limit their performance?

And what Jake said is how I remember the discussion going forth. Most just gave up!! Other things I heard were that the SIR either killed the power below competitive levels, or people blew motors....and that is not a cheap motor to rebuild!!

Another point, the e46 323. Same motor, but with double vanos, 3000#, same brakes, better aeor....yes the car to build at this point.

First, you need to look at the ITR times for E36's to more accurately gauge where ITS E36 development would or could be should it kept moving like the other cars. You are comparing cars at different points in time which is not fair.

Second, the 323 has a stock HP rating of 172hp. Can't be exactly the same motor as the 189hp 325.

[Greg Amy]

What is it exactly that you are asking for?

Send out a "what do you think?" on pulling the classification of the E36 with the restrictor in ITS. See if anyone is actually still running it.

Either revisit the great revision on the e36 or classify it the same as the e46 323, at 3000#

Chuck made me laugh.

How about instead, we get some dyno sheets on the E46 323 and consider increasing its weight accordingly, or tossing it into ITR at an appropriate weight? If it's pulling in over 210 pounds as you claim, it does not belong in ITS.

GA

[Andy Bettencourt]

Either revisit the great revision on the e36 or classify it the same as the e46 323, at 3000#

We already know the 323 is light. I have NOT seen dyno sheets but I can tell you that when one rolls by our S2000 at 205whp on the straights, it's got at LEAST 200whp. Reprocessed today at 12.9, it's 150lbs light. Using the napkin re-do I did above, it would be almost spot on but some stuff would get lighter. And if 200whp is soft for that car, it should weigh more.

Taking control of the cams via ECU is HUGE...if the 323 and the 325 can make the same whp, they should both be in ITR.

But if the 325 makes 220+ as we KNOW, ain't no way it's an ITS car.

[chuck baader]

OOPS...e45 has M52TUB25 motor and the e36 has the M50B25. The later motor is, in fact, less powerful than the earlier, and less responsive to IT upgrades.

I realize I am comparing cars from different times, however, there just aren't any R cars running at the tracks where I run to observe. The only R car I have seen more than one is Kips Porsche and he and Huffmaster put on a great show last year...that would be an ITS RX vs. ITR Porsche.

[JeffYoung]

Kip's car is obviously very well built and extremely well driven. However, I don't think he's gone less than 2:14 at VIR in it.

On the other hand, Skeen ran an ITR E36 at 2:11 or 12. That's about 2 seconds less than the ITS record (2:14) set by Chet Whittel in the Sunbelt E36.

That seems spot on for a "modern" E36 on new dampers, ECU tuning, tires and brake pads.

[JeffYoung]

Either revisit the great revision on the e36 or classify it the same as the e46 323, at 3000#

Huh? We know the car makes 215 whp so its process weight is 3300 or so. That's the only non-SIR option available other than ITR.

Sounds like you are looking for ANOTHER BMW overdog...lol.....

[JIgou]

In just this two-page thread, I've seen 215, 220+ and 230 quoted as the "known" horsepower level for an E36.

The discussions I've had with others who used to, but no longer, run an E36 325 said 215 was the top dog number, and those engines were only capable of that for a short period of time.

Is there legit, non-marketing-based dyno data floating around that can put THIS portion of the discussion to rest?

[Bill Miller]

So if you brought the multiplier from 12.9 to 12.25 you would get this:


170: 2675 --------> 2540
180: 2830 --------> 2670
190: 2990 --------> 2840
200: 3146 --------> 2990
210: 3305 --------> 3135*
220: 3460 --------> 3285*
230: 3620 --------> 3435*

* I submit there should be nothing in ITS making 210whp+

Yep

Correct, those cars should go into ITR.

That sure looks a lot more like "reality" above.

Double Yep

In which case, the discussion of the E36 325 in ITS is a moot point. Kill the SIR-equipped E36 from ITS.

GA

On edit: if we'd had ITR back then, that would have never happened in the first place. This is one of the car's that begat ITR's genesis...make it go away.

Exactly. The overdog status of the E36 325 in ITS was probably the single biggest impetus for the formation of ITR. And ITR has been around long enough, the dual classification of the E36 325 should be removed. If nothing else, it takes away ammunition from those that support dual-classification of more cars. I was honestly surprised that there was no sunset date on the dual classification, when it was announced.

Agree 100%. SIR has no place in IT.

I said that when the original Process was published / adopted, and it had the SIR language in it.

[JeffYoung]

In just this two-page thread, I've seen 215, 220+ and 230 quoted as the "known" horsepower level for an E36.

The discussions I've had with others who used to, but no longer, run an E36 325 said 215 was the top dog number, and those engines were only capable of that for a short period of time.

Is there legit, non-marketing-based dyno data floating around that can put THIS portion of the discussion to rest?

Here's what I know -- Jake has the real scoop.

The ITAC saw dynos in the 215 range. There were strong rumors that others had seen Sunbelt cars make 225 on a dyno but no sheets were kicked around.