UPDATE ST4/TT4 and other for 2017

[Racer Rick]

...but start to apply some reasonable limitations that the drivers (and their budgets) are accustomed to in PTB/PTC.

 

damn - guess I've been doing it all wrong all these years!

 

Ricky

[focusedintntions]

So with adding another power/weight class does this mean all nasa regions will begin having mobile dyno's at events for compliance checking? With points system it was easy enough to visually inspect. What is going to be done against "perceived" cheating?

[stevensa]

Any details on the reasoning for eliminating the non oem aero rule for XX3? If anything I would think it should be increased from 0.4 to 0.7 or so to make it a completely even choice. Even at 0.4, aero is the clear winner, by eliminating the mod factor altogether you basically need aero to compete at all.

[whoahstu]

So with adding another power/weight class does this mean all nasa regions will begin having mobile dyno's at events for compliance checking? With points system it was easy enough to visually inspect. What is going to be done against "perceived" cheating?

Points cars are still subject to a pw/wt cap and the dyno.

[Arca_ex]

To everyone complaining about the dynos, if you were a points car, and didn't have a dyno, you were likely not competitive anyways.

 

Points cars are still subject to an adjusted power to weight limit, subject to dyno protests, subject to doing dyno runs in impound etc etc.

 

Pretty much nothing is changing except if you were a points car that was so far away from the adjusted power to weight limit that you never bothered to dyno the car.

 

Personally I like it. If I have to do it and be subject to things like that, everyone else should too.

[Daniel Pyziak]

Greg, Regarding #7, There are a significant amount of BMW E36/46 race cars, via GTS 2/3, that have cage tie-in's to the rear subframe to help with known subframe issues. Might need to think about how to not exclude these cars.

 

-tony colicchio

TC Design

Yep. Agreed

 

Also agree!

[Mike W.]

So we are moving all the w2p down? TTB was 10.5:1 and FWD was a mod factor of 1. Now it is 12:1 and .6...yeesh. I was setting my car up to be a competitive B car but now it seems I will be a tweener car again. Not Mid TT3 and too much for TT4. Well hopefully I can get there with ballast.

1) ALL ST (1-4) and TT1-4 classes will use the Avg. HP calculation for Dyno tech inspections for compliance with the Adjusted Wt/HP Ratio.

 

For PTB it would be peak horsepower not average, have you done the calculation using your average HP?

[BlackCivic343]

So we are moving all the w2p down? TTB was 10.5:1 and FWD was a mod factor of 1. Now it is 12:1 and .6...yeesh. I was setting my car up to be a competitive B car but now it seems I will be a tweener car again. Not Mid TT3 and too much for TT4. Well hopefully I can get there with ballast.

1) ALL ST (1-4) and TT1-4 classes will use the Avg. HP calculation for Dyno tech inspections for compliance with the Adjusted Wt/HP Ratio.

 

For PTB it would be peak horsepower not average, have you done the calculation using your average HP?

 

 

It's going to be close, I will wait for everything to be finalized.

[Mrsideways]

To everyone complaining about the dynos, if you were a points car, and didn't have a dyno, you were likely not competitive anyways.

 

Points cars are still subject to an adjusted power to weight limit, subject to dyno protests, subject to doing dyno runs in impound etc etc.

 

Pretty much nothing is changing except if you were a points car that was so far away from the adjusted power to weight limit that you never bothered to dyno the car.

 

Personally I like it. If I have to do it and be subject to things like that, everyone else should too.

 

Your cap mathematically when using points is usually a significant amount higher then what you get handed with a dyno reclass

[Bluebarchetta]

Greg, Regarding #7, There are a significant amount of BMW E36/46 race cars, via GTS 2/3, that have cage tie-in's to the rear subframe to help with known subframe issues. Might need to think about how to not exclude these cars.

 

-tony colicchio

TC Design

Yep. Agreed

 

Also agree!

 

I support a rule set allowing inclusion, but I hope we aren't talking about allowing a modification for certain cars and not others. If we allow for some, it should be allowed for all.

[fxracer1]

I would also like to comment on the new PW/WT for the letter classes that are staying. It seems that the new proposed numbers are going to have a huge effect on all of the people that will be staying in those classes for next year and so on. I would have to guess that most people are going to have to either 1, lower their HP by a decent amount to stay in class, or 2, have no choice but to spend more money to move up to the next class if they want to be competitive. I LOVE the idea of ST/TT4, but it doesn't seem fair to penalize the lower classes in all of this. A lot of people have spent a lot of time and money to make their car as fast as possible within the class they are in, so instead of penalizing them by either making their cars slower, or having to spend more money and time to do more upgrades to move up, why not get rid of PT/TTC all together? All of the current B cars are probably making the move to ST3, all of the C cars are probably making the move to ST/TT4, and all of the lower ranks can stay as is. The base class system seems to work pretty well for the current PW/WT limits that are already in place so why force everyone to make their cars slower just to stay in class? Just my 2 cents!!!

[JHo]

I think it's a good start. I'm glad there are some mod factors to discourage some crazy tires and aero mods.

 

My biggest feedback is not a lot of special exceptions for specific cars. We all have our challenges with our chosen chassis. I know I will struggle to get to the power to weight ratio without a huge outlay of cash for a ticking time bomb of an engine. But it's something I chose to live with.

[davidfarmer]

My only input is regarding the power averaging formula. I like the fairness of it, but it is a PITA. Too much data, a single rpm dropout can ruin a pull, and none of my customers could do the calculations themselves this year

 

I'm all for averaging, just needs to be easier for your customers. Most dyno shops won't be as helpful as I am (being a Nasa guy myself)

[JamesMilko]

Other than the requirement to provide a dyno sheet if you are dyno classed I don't see a meaningful difference between the two within the context of the discussion here.

 

My only comment is that if you change the WT:PW for PTD/E/F please try to do it with high confidence that the post "ST" rules will be close to the same as the revised ratios so minimal changes will be needed. Rule changes aren't good for keeping people around.

 

If we go to average w:p can the 2001+ Miatas rejoin the rest of their friends with a non-* base class?

[Greg G.]

I would also like to comment on the new PW/WT for the letter classes that are staying. It seems that the new proposed numbers are going to have a huge effect on all of the people that will be staying in those classes for next year and so on. I would have to guess that most people are going to have to either 1, lower their HP by a decent amount to stay in class, or 2, have no choice but to spend more money to move up to the next class if they want to be competitive. I LOVE the idea of ST/TT4, but it doesn't seem fair to penalize the lower classes in all of this. A lot of people have spent a lot of time and money to make their car as fast as possible within the class they are in, so instead of penalizing them by either making their cars slower, or having to spend more money and time to do more upgrades to move up, why not get rid of PT/TTC all together? All of the current B cars are probably making the move to ST3, all of the C cars are probably making the move to ST/TT4, and all of the lower ranks can stay as is. The base class system seems to work pretty well for the current PW/WT limits that are already in place so why force everyone to make their cars slower just to stay in class? Just my 2 cents!!!

 

I believe you are incorrect. The combination of the Avg HP calculation, and the much different weight table in ST versus PT, would put most of the top current C cars at 14-14.5:1 (similar for most of the B cars with a few V8 exceptions). Most of the top D cars are already at 15:1 using the PT formula, and most of the top E cars are at 17:1.

[Greg G.]

My only input is regarding the power averaging formula. I like the fairness of it, but it is a PITA. Too much data, a single rpm dropout can ruin a pull, and none of my customers could do the calculations themselves this year

 

I'm all for averaging, just needs to be easier for your customers. Most dyno shops won't be as helpful as I am (being a Nasa guy myself)

David, we will be using our computer program for this, and will be supplying it to all of the Dynojet shops we can, as well as to the competitors to give to the Dyno shops, so they can put it on their computers, and spit out the Avg HP without the PITA.

[Jon B.]

I would also like to comment on the new PW/WT for the letter classes that are staying. It seems that the new proposed numbers are going to have a huge effect on all of the people that will be staying in those classes for next year and so on. I would have to guess that most people are going to have to either 1, lower their HP by a decent amount to stay in class, or 2, have no choice but to spend more money to move up to the next class if they want to be competitive. I LOVE the idea of ST/TT4, but it doesn't seem fair to penalize the lower classes in all of this. A lot of people have spent a lot of time and money to make their car as fast as possible within the class they are in, so instead of penalizing them by either making their cars slower, or having to spend more money and time to do more upgrades to move up, why not get rid of PT/TTC all together? All of the current B cars are probably making the move to ST3, all of the C cars are probably making the move to ST/TT4, and all of the lower ranks can stay as is. The base class system seems to work pretty well for the current PW/WT limits that are already in place so why force everyone to make their cars slower just to stay in class? Just my 2 cents!!!

 

I believe you are incorrect. The combination of the Avg HP calculation, and the much different weight table in ST versus PT, would put most of the top current C cars at 14-14.5:1 (similar for most of the B cars with a few V8 exceptions). Most of the top D cars are already at 15:1 using the PT formula, and most of the top E cars are at 17:1.

 

Agree with Greg on this. In our region, most of the B cars are welcoming the change to ST4/TT4 and would not be looking to move to ST3. If you run the numbers with the Avg HP calculation, in addition to taking into consideration the tire size modification (which I think should be in place for ST4 to account for those not wanting to run wider) I think you'll find that the change will work favorably for most. Overall, simplifying and consolidating the classing will end up being a huge positive for the majority of participants and help keep the officials more sane.

[fxracer1]

I would also like to comment on the new PW/WT for the letter classes that are staying. It seems that the new proposed numbers are going to have a huge effect on all of the people that will be staying in those classes for next year and so on. I would have to guess that most people are going to have to either 1, lower their HP by a decent amount to stay in class, or 2, have no choice but to spend more money to move up to the next class if they want to be competitive. I LOVE the idea of ST/TT4, but it doesn't seem fair to penalize the lower classes in all of this. A lot of people have spent a lot of time and money to make their car as fast as possible within the class they are in, so instead of penalizing them by either making their cars slower, or having to spend more money and time to do more upgrades to move up, why not get rid of PT/TTC all together? All of the current B cars are probably making the move to ST3, all of the C cars are probably making the move to ST/TT4, and all of the lower ranks can stay as is. The base class system seems to work pretty well for the current PW/WT limits that are already in place so why force everyone to make their cars slower just to stay in class? Just my 2 cents!!!

 

I believe you are incorrect. The combination of the Avg HP calculation, and the much different weight table in ST versus PT, would put most of the top current C cars at 14-14.5:1 (similar for most of the B cars with a few V8 exceptions). Most of the top D cars are already at 15:1 using the PT formula, and most of the top E cars are at 17:1.

 

I see your point Greg. That was just my first though pertaining to my own situation. Will most of those top D cars already Dyno Re-classed to the 15:1 stay where they are at? I am re-classed in D at 14.25, and I assume its because I am FWD and you factored in the FWD MOD factor. If I had to be back at 15:1 with everyone else, that would hurt me. Do you plan on redoing all of the Dyno Re-classes of those top cars and put them back at 15.75 or so to keep all factors the same for everyone involved that has to take the HP loss? I realize this may not be the place to ask these questions, if its not then let me know. It just seems like the Top cars in class will stay where they are at, and everyone else may have to take a loss somewhere.

[Mrsideways]

My only input is regarding the power averaging formula. I like the fairness of it, but it is a PITA. Too much data, a single rpm dropout can ruin a pull, and none of my customers could do the calculations themselves this year

 

I'm all for averaging, just needs to be easier for your customers. Most dyno shops won't be as helpful as I am (being a Nasa guy myself)

David, we will be using our computer program for this, and will be supplying it to all of the Dynojet shops we can, as well as to the competitors to give to the Dyno shops, so they can put it on their computers, and spit out the Avg HP without the PITA.

 

Why not just copy the way the GTS site does it. Log into site, input numbers print results.

Edited September 15, 2016 by Guest

[Balroks]

My only input is regarding the power averaging formula. I like the fairness of it, but it is a PITA. Too much data, a single rpm dropout can ruin a pull, and none of my customers could do the calculations themselves this year

 

I'm all for averaging, just needs to be easier for your customers. Most dyno shops won't be as helpful as I am (being a Nasa guy myself)

David, we will be using our computer program for this, and will be supplying it to all of the Dynojet shops we can, as well as to the competitors to give to the Dyno shops, so they can put it on their computers, and spit out the Avg HP without the PITA.

 

Why not just copy the way the GTS site does it. Long into site, input numbers print results.

 

 

^this. HTML versions will be far easier to access and maintain. However...the issue then is most dyno shop computers don't have Internet access. So a windows based program running locally can do it faster for those people rather then thumb driving it back and forth.

 

For the tire width, why not a restriction in 1-3 as well if you're gonna do it in 4. Like 1=315, 2=295, 275, and 255 and so on. Then you'd only have mod factors for compound. The scenario I think of is say in 3, a S2k vs a Vette. Both are RWD but a vette can fit 315's a's all day where a s2k cannot take the same advantage physically for around the same $. If the goal is controlling costs for closer competition that is.

[gkmccready]

For the tire width, why not a restriction in 1-3 as well if you're gonna do it in 4. Like 1=315, 2=295, 275, and 255 and so on. Then you'd only have mod factors for compound. The scenario I think of is say in 3, a S2k vs a Vette. Both are RWD but a vette can fit 315's a's all day where a s2k cannot take the same advantage physically for around the same $. If the goal is controlling costs for closer competition that is.

 

And you're forgetting the weight difference between those cars...

[erik911]

Slightly off topic, and I know all the details are final, but has there been discussion of how ST4 would cross to the Enduro classes? Would think these would cross to E1 class similar to PTC?

 

Erik

[Sterling Doc]

Many of my ST3 guys are using peak HP for their calculations, and leave the "Avg" HP as their cushion for dyno variation, especially the V8 guys w/o DBW flattened curves. They may be leaving a little on the table, but keeps them safe in the compliance dynos we've done so far.

[Brian L.]

For the tire width, why not a restriction in 1-3 as well if you're gonna do it in 4. Like 1=315, 2=295, 275, and 255 and so on. Then you'd only have mod factors for compound. The scenario I think of is say in 3, a S2k vs a Vette. Both are RWD but a vette can fit 315's a's all day where a s2k cannot take the same advantage physically for around the same $. If the goal is controlling costs for closer competition that is.

 

And you're forgetting the weight difference between those cars...

 

Correct! That is why a tire to weight size factor needs to be considered. Rather than restrict tire size by class, restrict tire to weight ratio's for the classes. For Example...

 

ST3 = 10:1 power AND 10:1 tire.

- 3150 lb Vette/Z can run 315's

- 2750 lb BMW/S2000 can run 275's

- 2450 lb FWD Honda can run 245's

 

ST4 = 12:1 power AND 12:1 tire

- 3150 lb Vette/Z could run 275's

- 2750 lb BMW could run 245's

- 2450 FWD Honda could run 205's

 

You could also easily adjust for cars that don't weight exactly what tire size they are using. For example...

 

ST4 BMW on 245's = 2750 lbs/245mm = 11.2 lbs/mm, .8 over the limit. So just subtract .8 from the allowed power to weight? This would also allow people that have already fit oversized tires on their car to play, they just need to lower they rev's/tune to a slightly lower power.

[Mrsideways]

fyi, I punched in my current dyno numbers to the GTS sheet and it came back 1 hp different from doing it the way currently described on the NASA TT3 sheets. And it was a lot easier.