Rules for 2013

[brucesallen]

tork at the wheels is meaningless is just what i'm saying ! tork numbers at the wheels change greatly they are for the most part are taken in top gear but on cars were you can change out your gearing at the rear axle at any time in the matter of minutes it becomes a plus if your playing with numbers and how you want your car classed . on the other hand for motors on motorcycles and snowmobiles the tork and hp numbers are taken at the counter shaft not the crank .

You can change the rear-end all you want, it shouldn't alter your dyno results significantly on a modern load sensing dyno (Mustang, Dyno Dynamics etc). The dyno is only measuring HP, torque is just displayed as a factor of HP over RPM.

So, in fact, torque shown on a dyno sheet is not the wheel measured torque but a calculated shaft torque, right??

[brucesallen]

And another point: I would not like to see all the classes shift because it rains and people put in rain tires. Chaos for the scorekeepers. And season's points would get shifted to another class.

[962porsche]

bruce
the motor i have for my car that is totaly built was dynoed by the engine builder out in colorado on his engine dyno .
motorcycle motors can not be dynoed at the cranks . they can only be dynoed at what is called the counter shaft that is were the sprocket bolts onto . the reason is one side of the crank has the ignition system and the other side is called the wet side that is were the gear oil is . so the power numbers are given after it goes thru the gear box .

the mild built motor i have was dynoed on a mustang chassis dyno 3 years ago when my friend jeff atwood 1st bought it . i brought my car over to his place on a sunday and we played around with doing things .
one other thing we found out is if you just change the tire pressure in the tires you can change the numbers you get . along with how hard you strap the chassis down in the dyno .

[dtlemoine]

And another point: I would not like to see all the classes shift because it rains and people put in rain tires. Chaos for the scorekeepers. And season's points would get shifted to another class.

Generally I agree that weather would be a sh*tty way to bump up a class BUT... we should note that Hoosier Wets are classed the same as R/SM6s, v710s, R1. Generally folks that I know don't come to the track with a set of street tires for the TT, and Hoosier Wets as their wet weather backup. If you carry Hoosier Wets to the track, you're *probably* running something similar in the dry from the aforementioned group.

If you're in a one off situation where you set up your car to be maxed out in a class with a Nitto NT-01 in the dry with no points to give, then tough luck. Consider building a buffer in your setup to account for last minute changes at the track (maybe take off those aftermarket sways in the rain and save some points there!).

[Chrispy]

So, in fact, torque shown on a dyno sheet is not the wheel measured torque but a calculated shaft torque, right??

The torque is reverse calculated from wheel HP using (5252 X hp)/rpm. So basically it is crank torque with drive-train loss subtracted. I suppose you could call it shaft-torque but I've only every heard that expression when talking about electric motors.

Edit: Torque is only reverse calculated from HP on inertia dyno's (Dynojet etc), for load absorbing dynos (Dynodynamics etc) torque is measured and HP calculated. Either way torque and HP have a fixed relationship based on RPM.

[Chrispy]

And another point: I would not like to see all the classes shift because it rains and people put in rain tires. Chaos for the scorekeepers. And season's points would get shifted to another class.

Generally I agree that weather would be a sh*tty way to bump up a class BUT... we should note that Hoosier Wets are classed the same as R/SM6s, v710s, R1. Generally folks that I know don't come to the track with a set of street tires for the TT, and Hoosier Wets as their wet weather backup. If you carry Hoosier Wets to the track, you're *probably* running something similar in the dry from the aforementioned group.

If you're in a one off situation where you set up your car to be maxed out in a class with a Nitto NT-01 in the dry with no points to give, then tough luck. Consider building a buffer in your setup to account for last minute changes at the track (maybe take off those aftermarket sways in the rain and save some points there!).

I was just considering that last scenario you mention. Hoosier H20's are 4 points more than Nitto NT-01's (if you include the Hoosier sizing penalty), but most people will be running their wets considerably narrower than dry weather tires so it is possible to shave off the difference that way.

[nhsilversti]

why is there such a large spread of points for DOT tires? i understand some DOT tires are faster than others when new or low heat cycles. maybe reducing the points for DOT tires could help lessen the chance of getting bumped to another class strictly from a tire change perspective. 1, 2, or 3 points instead of 1, 3, 8 points and make non-DOT tires 10 points which WILL bump you to the next class in all cases.

ted

[dtlemoine]

I was just considering that last scenario you mention. Hoosier H20's are 4 points more than Nitto NT-01's (if you include the Hoosier sizing penalty), but most people will be running their wets considerably narrower than dry weather tires so it is possible to shave off the difference that way.

I think that's a great point. Going down by 10mm in most (all?) touring classes will net you -1 assessment point relative to where you started, so if you happen to run the Nittos in the dry and Hoosiers in the wet, going down by 30mm will make up the difference (pending the response to my question below). If you're running streets in the dry and Hoosiers in the wet, well, you still have additional buffer you'll need to account for. This is probably a very small minority of our club, but I could be wrong.

Question for the authors - does the +1 point penalty for Hoosier/BFG apply to Hoosier Wets as well?

[Chrispy]

Question for the authors - does the +1 point penalty for Hoosier/BFG apply to Hoosier Wets as well?

Nick says yes since they fall under the Hoosier DOT-R category. So that means they would have to be 40mm narrower to be on equal points footing with NT-01's.

From what I have seen at the track I don't know of anyone that runs street tires in the dry and H20's in the wet. Only exception might be if they were to borrow a set for a TT run.

[chaos4NH]

as the car sits now i have the motor in it with a mild build . why the motor.......n weight ? because on a H.H.H. day i will use thoughs things .
bet your ass they are or will !

Dude, it hurts my brain to try to follow you here. You may have some points in there, but please stop overthinking this, try to remember we're all going to the track for fun.

Can you hide stuff and cheat ? Yes. You can do that now. Can you make small changes that move you between classes? yes. Will other people try to bend the rules? Yes. They can also do that now.

Tom, wouldn't we have to submit a classing sheet for each event? Or only when we admit to adding assessment points?

[blindsidefive0]

Good discussion...I feel like the qi of this thread is getting a bit better with these kinds of topics.

Honestly, I think if you ask Pete, Paddy, and I why we even bothered to put together a system like this...it would be tires. Tires represent the single most effective modification for any vehicle to improve performance. They are also pretty damn expensive (running fresh DOT-R tires could cost you thousands for a season) and can vastly skew competition between new guys (likely on street tires) and seasoned track rats (with their fancy "purple crack"), even in Showroom Stock classes. I have, at multiple race tracks, dropped 4s+ off my lap time just by switching tires. Based on estimated lap-time spread between classes, if anything the DOT-R tires may be UNDER-assessed slightly. We spent a ton of time on this very item to attempt to balance a fair tire assessment with making sure someone's tire budget couldn't buy them a victory.

A good test of the DOT-R tire assessment would be if folks still run them next year or opt for street tires instead. I hope (and would bet on) most folks towards the bottom of a class feeling like the tire assessment for DOT-R's is a good "investment" of points where folks towards the top of a class opt for the NT01 or high performance street tire.

As for old tires...under the new system if you running "bad" or "cycled out" DOT-R tires, you are doing it wrong. For pretty cheap you can pick up a set of new Hankook RS3 street tires that are within 1-2s of the NT01/RA1/etc. They won't heat cycle like old Hoosiers, you won't have to take nearly as many points, and you can drive them to the track...

Honestly, our hope is that you can finish off those Hoo-Hoo's at NHMS-4 and the 2013 Test Day* (depending on schedule), and then start running the most cost effective/competitive tire for you and the class in which you want to run.

[Mick]

Personally, I'm looking forward to being able to run harder tires. RA-01's drop me into the next lower class. That's a win/win in my book.

[Georgethefierce]

I agree that the biggest gap between the"haves" and the "have nots" is tires, it's the great equalizer

[dtlemoine]

We spent a ton of time on this very item to attempt to balance a fair tire assessment with making sure someone's tire budget couldn't buy them a victory.

Nick - you nailed it on the head with this statement. I think alot of folks are looking at the super classes as a moneypit, and not taking a step back to assess the system as a whole, including the touring classes, which based on the conversations I've seen will be where the majority of the club lands.

The authors put a ton of time into the initial classing of the cars, taking into consideration existing COM rules, NASA, CASC, and various other information available on the interwebs. NASA is incredibly popular in the US and their system gets great reviews. I can only assume the same for CASC, as there doesn't seem to be anyone else doing something similar north of the border. Short of hiring the Stig to pre-class all of our cars, there is no better way to baseline than power & torque / weight. Cars were then given a bump up/down based on their relative competitiveness of cars with the same power/weight.

At this point, every car in each class should be +/- a couple seconds of every other car in their class in its stock form. For under a grand, you can add nice adjustable shocks and swaybars and get yourself close to the top, depending on where you stand. From there, invest in 1 set of Hankook R-S3's or Dunlop Star Specs for the entire season and you can be competitive, in the dry and wet.

Compare this to the current system where folks are showing up with sticker R6's a couple of times/year (not to mention the Hoosier H2O's in the trailer), and you're not even close when you start to count up the $$. This system significantly reduces the average spend to keep a car competitive, and allows flexibility for folks to run their true street cars that they've done a little work to (e.g. minor suspension) to still be competitive, rather than dropping them into ST to compete against cars that were dragged in on trailers with seats and full cages.

Folks who have pointed out that there are vast discrepancies between results of low HP racecars at NH vs. some of our away tracks - this is valid, but I've never seen a system that can successfully mitigate the issue. Also, 66% of the events in the past 4 years have been at NH or NJ, so the proposed scoring system is in your favor more times than not.

For folks who think you will get killed at the bottom of the super classes - run this weekend and see how the results shake up. If there are glaring issues after this weekend, propose tweaks to the system to the authors; I know they are open to feedback if its constructive.

Nice work Nick, Pete, Paddy - looking forward to competing next season with the new system!

[Shawn624]

I agree that the biggest gap between the"haves" and the "have nots" is tires, it's the great equalizer

+1