STL engine builds?

Rabbit07 said:
Riddle this to me regarding the BP Miata;

A SM can make 131 WHP through 41mm restrictor.

I know of ITS Miatas that have made north of 160 WHP with stock cams and .5 increase in compression ratio.

How can a major increase in cam shaft, compression, lighter flywheel, lighter rotating assembly, stand alone engine management, not make atleast 180 WHP?
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Because nobody has done one. A well known builder up here had ideas on what an ITA motor COULD make given what he saw from unknown engines and SM 'data'. Guess what? SAME NUMBERS as I make and have been quoting. These things are just not linear. The ISC cars make ~ 155whp on a 'regular dyno', not the optimistic one they use to tune. I am not sure what is possible because I have never done one but I can tell you that traditional upgrades don't take effect like some other motors. Stand alone engine management is the big HP bump in these motors and it's included in the IT number already. Build one. I can't wait to see the results. If it makes the number, you have a second legit choice.

Run the math, in order for a Miata to be equal to a 185whp Honda on paper, what will it have to make?
 
The whole point is that even IF the Miata proves to make the power (those of us with actual IT build experience know those limitations) it will still only be one of two choices.

OPEN UP THE CLASS to the 13B and older chassis with modern motors. This will at least get people interested in exploring options. People looking from the outside in see that they need 185whp in a FWD car and at least that out of their RWD to be close on paper.

Yikes.
 
Andy Bettencourt said:
Edit-Edit: I believe enough in the LAP SIM stuff to suggest that at these power levels, there should be a 5% difference in FWD-RWD given the same front suspension design.

Math example:

GSR 1.8 into a HondAcura with double wishbone fronts: 185whp. THAT is the target everyone is looking at when deciding to build. In order to hit that number, what will a RWD 1.8-based car have to make for power to be on par? How about the 1.6's? Let's do some math.
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Easy, 5% of 185 is 9.25 -> so let's just round it to 10hp -> so any 1.8 liter rear wheel drive platform will have to make 175hp at the wheel.
 
Z3_GoCar said:
Easy, 5% of 185 is 9.25 -> so let's just round it to 10hp -> so any 1.8 liter rear wheel drive platform will have to make 175hp at the wheel.
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Just to provide info, not asking or suggesting that this is or should be allowed:

175 at the wheels: This is about as much as a BMW S14 2.3L can make under the STL ruleset because of the cam lift restrictions, maybe 182 at best on a well built fresh motor. That would require weighing 2990#. At Watkins Glen, that would be a lap time of around 2:15-2:16, and at mid-ohio around 1:44-1:45. NHMS would be around 1:15 (remember 7inch rims not 8)

If STU cam lift specs were allowed on an other wise STL BMW S14 2.3L engine, then 205 at the wheels is a realistic max. That would translate into appx 2:39-2:40 at RdAm.

I've done some investigating - the Toyota 3S-GE was run in WC-TC - a private entry with Toyota factory support. The engines all blew up. All of them. So on paper it might make sense, but in the real world...maybe not so much.

Side note - It seems to me the ITR and S2K - don't have a place to be competitive in either STL or STU. (Can't get down to weight in STU)

Anybody know what the reasoning is behind not allowing turbo cars in STL at all - not even 2wd turbos?
 
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Andy Bettencourt said:
OPEN UP THE CLASS to the 13B and older chassis with modern motors. This will at least get people interested in exploring options.
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I agree but 40-50 posts ago it was explained this is a "< 2L Tuner class". It is an arena for <2L FWD cars to race and compete.
 
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We have the power to adjust the 13b and the 12a. However, until we have some real world on track data, there is no current desire to adjust them. Like I have said before, We looked at the numbers chose a weight. I know I have driven some really fast ITS RX7's, so I don't see how these cars won't be competitive? If they aren't then we can always give them a weight break.
 
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Chris, you seem like a great guy and really appreciate you posting here on ST matters. I'm building my LAST two engines for the TR and starting to think aout what's next with their really being three options:

1. A modern IT car (S or R);
2. An STL car; or
3. A V8 thingamajig for the N-word club.

When I read something like the below, I get spooked about STL. Badly. I thought the classing "intent" behind STL was to be even MORE objective than IT. Meaning a straight formula with no subjective adders like we have.

Now the below suggests not only is the classing not entirely objective as (I thought) advertised but "real world on track data" will be used to adjust weights and subjective "feel" about whether a car can be competitive is driving weighting decisions?

While I get and appreciate Greg's reasoning as to why the 13b RX7 went into STL at the ITS weight with no real ability to increase performance, objectively speaking it looks odd that the ITS Integra goes into STL (a car roughly equal to the 13bRX7 in ITS) at something like 300 lbs less and with the ability to improve on the already stout 175ish whp figure they are making?

And we are justifying this because you drove a few fast ITS RX7s and think they can be competitive?

I'm seriously not trying to bust your chops but truly trying to understand the philosophy behind weight setting in this class.

Rabbit07 said:
We have the power to adjust the 13b and the 12a. However, until we have some real world on track data, there is no current desire to adjust them. Like I have said before, We looked at the numbers chose a weight. I know I have driven some really fast ITS RX7's, so I don't see how these cars won't be competitive? If they aren't then we can always give them a weight break.
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Un true. Data does not lie. We are not talking about results. We are talking about hard data. This is very objective. It is easy to calculate the Power level of a car by how it runs in a certain distance. Particularly regarding a dyno pull like Road America. Really all we are concerned about is are the cars working together as expected or not. No special favors, no deals, etc....

On edit; If the 13b or 12A looks like it isn't working as a similar weighted piston engine, then it can be adjusted. Proof is gonna be in the pudding.

On Edit Part Deux; We objectively selected the weights on the Rotaries from known power numbers. That is why we feel they are correct. Again because we had an expected power output per liter. Nothing more or less.
 
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Hard data like what?

How are you going to correct for air temps, humidity, grip levels, etc.?

So what you are saying is that the objective displacement based formula can be modified via time/distance on track horsepower calculations??

Rabbit07 said:
Un true. Data does not lie. We are not talking about results. We are talking about hard data. This is very objective. It is easy to calculate the Power level of a car by how it runs in a certain distance. Particularly regarding a dyno pull like Road America. Really all we are concerned about is are the cars working together as expected or not. No special favors, no deals, etc....
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This one still gets my goat.

WHY?

When we were looking at Lapsim, I discovered that the only "input" into the program for "FWD" was checking a box that said that. I sent an e-mail to the company that makes the program and asked them to explain what this changed in the program. No response. No one on the ITAC was ever able to explain how Lapsim modelled the FWD "deficit," what factors it used, etc. It just spit out differing lap times with no explanation.

You want to talk about black box car classing/weighting, that's about as black and box as it gets....lol....

Andy Bettencourt said:
.

Edit-Edit: I believe enough in the LAP SIM stuff to suggest that at these power levels, there should be a 5% difference in FWD-RWD given the same front suspension design.
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SCCA Data boxes in cars at the same event, during the same race. This is what the CRB has been using to check parity in all the classes for the last several years. It has worked quite well.
 
So this is going to be a rewards weight class? Meaning that if someone performs well versus other cars at a particular event, there will be a weight adjustment?

Maybe that works well for Prod, GT, Touring, etc. but I'm pretty sure most IT guys would want nothing to do with that.

Rabbit07 said:
SCCA Data boxes in cars at the same event, during the same race. This is what the CRB has been using to check parity in all the classes for the last several years. It has worked quite well.
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Not even. But if a car looks like it is an over dog you will need to look closer.

No rewards weight in club. I have this conversation a lot with many people in club racing. There are some really smart people volunteering in this club on the committees and on the CRB. These are racers, engineers, race car builders, etc.

I can tell you without a doubt that the members of the STAC are some of the most objective people I have ever had the honor of spending time with.

On the Rotaries what do you propose we do? If they are not where they should be as Andy has said, should we stick to our guns? Never change anything and let them not compete if that is the truth?
 
JeffYoung said:
So this is going to be a rewards weight class? Meaning that if someone performs well versus other cars at a particular event, there will be a weight adjustment?

Maybe that works well for Prod, GT, Touring, etc. but I'm pretty sure most IT guys would want nothing to do with that.
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How is this fundamentally different than the ITAC being able to adjust the horsepower improvement factor away from the assumed 25-30% when evidence is presented? The STAC might use a different sort of evidence, but I don't hear them saying they plan to do wholesale adjustments.

Dave
 
I have no doubt about the dedication and good movitations of the guys on the STAC.

I still see a lot of contradiction in both your post above and in what I thought was the philosophy for this class, versus what may happen in practice. I do think some of it is you guys bumping up against the fact that you need some ability to deal with the unexpected overdog. We do it with dyno data and power expectations. You guys do it with on track data but it's all the same.

I would suggest to you though that you be up front about this as soon as possible and as often as you can. People need to know what they are getting into.

The RX7? I have no idea really other than it is clearly heavy vis a vis its competitors in ITS that are moving into STL.

I wish you guys and the class the best but I think the very narrowly defined competitive performance envelope you have come up with and at least the appearance that only a Honda/Acura chassis/engine combination is going to work is really going to hamper things.

We've had enough trouble getting ITR up and running where at least on paper there are 15-20 cars that should have a shot.
 
Greg and I both had posted earlier the section that mentions that we have a power to weight expectation and that cars may be required to install data boxes. Is that not up front? If not maybe we need to look a bit closer at how it reads. We all look at the rules so long your eyes start to miss things.
 
Personal Opinion/Editorial Follows

When I'm posting on this forum, I'm speaking for myself ("see my sig", blah, blah, ad nausea). Unless I specifically say something like "this is a fact" or it can be reasonably implied as such, it's just that: an opinion.

Chris' posts should be inferred exactly the same.

That said, I will not personally (read: opinion) support individual "competition adjustments" in Super Touring Light. IMO, this class is that it is, all there in black and white. It's certainly possible we could adjust adders/subtractor percentages (e.g., RWD v FWD - which I personally think is too light - or FWD struts) and it's always possible (but not even being CONSIDERED at this point) to add general adjusters based on other physical characteristics.

But I will personally oppose comp adjustments on individual cars, engines, and stuff like that. I was attracted to STL as a competitor both because of the general ruleset and the clear-cut "here's the rules, pick your poison" attitude. "It is what it is".

Again: general adjustments, I'm open-minded. Individual car classification/adjustments? I'm out.

Andy, one last time: I personally don't see the rotary as within the philosophy and intent of STL. We "include" the rotary IT cars at their current IT weights, and if you want to "seriously" play within the ST ruleset (are you even thinking of participating in this class?) we give those engines very good (and competitive) places to play in STU at a modification level comparable to the remaining Super Touring philosophy. The listed inclusion of the rotary engine in STL in unmodified spec is, IMO, comparable to allowing IT and SM cars to come play "without guarantee of competitiveness", and is in there to cover the obvious answer that you pointed out, that the engines are already sub-2-liter (yes, we know about the Renesis.)

Continuing to ask "why?" is not going to change the answer.

But I find it extremely encouraging that all of you are finding this new class attractive enough to actually "give a shit" about how cars are classified in it. Keep going, there's some good points in here.

GA
 
Greg Amy said:
Personal Opinion/Editorial Follows

When I'm posting on this forum, I'm speaking for myself ("see my sig", blah, blah, ad nausea). Unless I specifically say something like "this is a fact" or it can be reasonably implied as such, it's just that: an opinion.

Chris' posts should be inferred exactly the same.

That said, I will not personally (read: opinion) support individual "competition adjustments" in Super Touring Light. IMO, this class is that it is, all there in black and white. It's certainly possible we could adjust adders/subtractor percentages (e.g., RWD v FWD - which I personally think is too light - or FWD struts) and it's always possible (but not even being CONSIDERED at this point) to add general adjusters based on other physical characteristics.

But I will personally oppose comp adjustments on individual cars, engines, and stuff like that. I was attracted to STL as a competitor both because of the general ruleset and the clear-cut "here's the rules, pick your poison" attitude. "It is what it is".

Again: general adjustments, I'm open-minded. Individual car classification/adjustments? I'm out.

Andy, one last time: I personally don't see the rotary as within the philosophy and intent of STL. We "include" the rotary IT cars at their current IT weights, and if you want to "seriously" play within the ST ruleset (are you even thinking of participating in this class?) we give those engines very good (and competitive) places to play in STU at a modification level comparable to the remaining Super Touring philosophy. The listed inclusion of the rotary engine in STL in unmodified spec is, IMO, comparable to allowing IT and SM cars to come play "without guarantee of competitiveness", and is in there to cover the obvious answer that you pointed out, that the engines are already sub-2-liter (yes, we know about the Renesis.)

Continuing to ask "why?" is not going to change the answer.

But I find it extremely encouraging that all of you are finding this new class attractive enough to actually "give a shit" about how cars are classified in it. Keep going, there's some good points in here.

GA
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With this being said, I am almost 100% certain that I am done with STL. As long as there is a member of the STAC driving the class overdog car and openly states that he will "oppose comp adjustments on individual cars, engines, and stuff like that" I will take my car elsewhere.
Thanks for making this an easy decision Greg.
 
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