First comment/suggestion on the new TT rules (from me)

[warrtalon]

I'm actually quite pleased with the new rules simply because of the new TTS class. I didn't even look at the changes to the points system, because I had little-to-no chance of staying in TTA, and I was worried about getting swallowed up by 500+whp cars in TTU. However, now I have TTS, within which I fit easily at 3350+ lbs and 300-ish WHP. I can go as high as 385whp, which is going to be about my upper limit at sea level (currently at 6000'), so I should be in good shape with my current mods. At least I won't be able to complain about being beaten simply by outright HP - now it will be simply because of inferior driving.

 

However, my only issue is this text:

 

"Dynamometer tests must be conducted on a Dynojet Model 248 or 224 for front and rear wheel drive vehicles, and on a Dynojet, Mustang, or Dynapack for AWD cars, in a commercial facility that offers dynamometer testing as part of their business and is open to the public."

 

I live in Colorado Springs, and the only AWD dyno here is a Dyno Dynamics, which is considered one of, if not THE premier dynos in the country in terms of quality and features. I already have my verified SAE numbers that are repeatable and accurate, but the DD brand is not included in the TT rules. I recognize the Dynojet, Mustang, and Dynapack as legitimate dynos, too, but why not the DD? Was this on purpose, or was it an oversight? I would much rather utilize my local dyno, which is very much a legitimate and proper dyno, rather than driving to another city to dyno, if possible. What do you think, Greg?

[mrc24x]

I agree warrtalon. My car got hit pretty badly w. points, +7 more base, +10 for stock tire size (ouch), +3 more for v710's, +another 6 if I want to run the optimum tire size......so without touching my car from last year it went from TTC to TTA. I did prepare the car well and it was probably an overdog for the class but I feel bad for the other more street friendly C4's (Corvette).

 

Bottom line is that I can add what I want now with ST and not worry about points. Nice and simple.

[IGZOSTD]

I have to agree , although I was looking forward to TTC next year , my car was bumped a class and with the tires I run I am now in TTB . Yes the tire hit was BIG .

I do like the new points system except for the restriction on accesing the ecm for timing changes . I would like the ability to retard the timing at the track , I run as much advance as possible with the fuel I use , so if anything , my reprogramer is now kind of a wast of money .

Looks like a lot of hard work went into the rules . I think this will make a better program for all .

Thanks Greg

[Varkwso]

My last year legal TTB C5 FRC is now running in TTS with the big boys as it sits I think - it might possibly stay in TTA - but I doubt it. The tire hit was +26 points alone. Adding up the rest +7 for base class, +4 for headers/exhaust, +1 for zip tie mod on air cleaner, + a lot since the car is under the 3248 cited for C5s or +1 for the drivers seat - I think plus a few I am sure I have overlooked.

 

It is no way competitive in TTS as it sits without mega dollar infusion - I doubt my 2002 ZO6 is competitive either. Glad I got to the track to have fun!

[Greg G.]

I have to agree , although I was looking forward to TTC next year , my car was bumped a class and with the tires I run I am now in TTB . Yes the tire hit was BIG .

I do like the new points system except for the restriction on accesing the ecm for timing changes . I would like the ability to retard the timing at the track , I run as much advance as possible with the fuel I use , so if anything , my reprogramer is now kind of a wast of money .

Looks like a lot of hard work went into the rules . I think this will make a better program for all .

Thanks Greg

 

The problem with being able to retard your timing after competition begins is that we can no longer have the opportunity to Dyno test the car if necessary as it was in earlier competition.

[Greg G.]

 

However, my only issue is this text:

 

"Dynamometer tests must be conducted on a Dynojet Model 248 or 224 for front and rear wheel drive vehicles, and on a Dynojet, Mustang, or Dynapack for AWD cars, in a commercial facility that offers dynamometer testing as part of their business and is open to the public."

 

I live in Colorado Springs, and the only AWD dyno here is a Dyno Dynamics, which is considered one of, if not THE premier dynos in the country in terms of quality and features. I already have my verified SAE numbers that are repeatable and accurate, but the DD brand is not included in the TT rules. I recognize the Dynojet, Mustang, and Dynapack as legitimate dynos, too, but why not the DD? Was this on purpose, or was it an oversight? I would much rather utilize my local dyno, which is very much a legitimate and proper dyno, rather than driving to another city to dyno, if possible. What do you think, Greg?

We chose to limit the AWD's to these three AWD dynos because we thought that every region would have at least one of the three available at not too great a distance. I personally do not know how the Dyno Dynamics numbers compare with Dynojet numbers. If you know, feel free to post here. I can look into the Dyno Dynamics as well.

[slink]

i feel your pain varkwso. my ttc s2000 is now a tta . do i try to remove 5 points to stay in ttb or add 14 point after the intial shock i figure verybody else was hit the same way. so i will see the same jump in points from other cars also.

[Varkwso]

i feel your pain varkwso. my ttc s2000 is now a tta . do i try to remove 5 points to stay in ttb or add 14 point after the intial shock i figure verybody else was hit the same way. so i will see the same jump in points from other cars also.

 

I saw the hit on everything - my wifes 'O5 GTO would bump a class just with stock size tires in a r compound (and it needs it to be safe at speed). If I cannot keep the FRC in TTA there is no point for me to enter TTS except to make the field large. In my platform of choice I already know of several ex-T1 ZO6 vettes that will be in TTS - I am not competitive to the lap times of those cars with either of mine. That does not even count the other players in TTS (an AWD Turbo car - most any make - leaps to mind).

 

Hope somebody comes out with some track tire sizes or sticky street tires (affordable would be even nicer) that are a viable option for a C5 - the only way I can see getting down enough to play with my FRC.

[Valhakar]

I am a bit of a logging and progression nut. Consider my WRX addiction half speed, half mad scientist.

 

Dyno Dynamics is a "heatbreaker and will readu MUCH lower than a Dynojet/Mustang. A Dynapack removes the wheels and measures horsepower at the hubs. For this reason it reads much higher. I have seen as much as a 7 HP variance at 200 WHP with Dynojet and Mustangs.

 

From low to high

 

Dyno Dynamics

Mustang

Dynojet

Dynapack

 

My car showed nearly 240 WHP on a Dynapack and only could pull a 13.9 1/4 mile with a decent 60'. Trap speeds were UNDER 98 MPH. The next week I ran on a Dynojet and only showed 220 WHP.

 

The problem is each dyno is different and some can even be calibrated. Long of the short, you cannot trust a dyno. The gap from a Dyno Dynamic to a Dynapack can be as much as 40 WHP on a "227" crank HP AWD car.

[warrtalon]

Actually, no, a DD will usually read lower than a Dynojet, but not a Mustang Dyno. A Mustang Dyno that is properly calibrated will read almost identical to a DD. However, people can change the roll weights of the rollers on a Mustang Dyno to make it read like a Dynojet or anywhere in between. That's the inherent problem with using any or all of these dynos - none read the same.

 

Greg, a Dyno Dynamics can read up to 15% lower than a Dynojet just like a Mustang Dyno. None of them read the same as a Dynapack. Also, a DD is far superior to both Dynapacks and Dynojets, fwiw. Mustang dynos are also very good.

 

Lastly, as I've said before, forcing SAE is not good, because up at 6800' here in the Springs, the SAE CF is 1.32 at times, which is WAYYYYYYYYYYYYY too high for forced induction cars. SAE is ONLY for N/A cars, and that HAS to be considered. You don't notice the major difference at sea level, because there is no calculation for barometric pressure - just temps and humidity. But up here, we have a gigantic correction for the lack of atmospheric pressure that has been verified to only work for N/A cars. I dyno'd at sea level then at this altitude, and the SAE numbers up here were 40whp higher than actual...

[GAC]

Lastly, as I've said before, forcing SAE is not good, because up at 6800' here in the Springs, the SAE CF is 1.32 at times, which is WAYYYYYYYYYYYYY too high for forced induction cars. SAE is ONLY for N/A cars, and that HAS to be considered. You don't notice the major difference at sea level, because there is no calculation for barometric pressure - just temps and humidity. But up here, we have a gigantic correction for the lack of atmospheric pressure that has been verified to only work for N/A cars. I dyno'd at sea level then at this altitude, and the SAE numbers up here were 40whp higher than actual...

 

This is correct. CFs don't work correctly on FI cars that effectively have internal atmospheres and benefit sometimes from the passive cooling effect of humidity. Now temp. DOES matter, and there must be someway to equalize readings in various parts of the country on different days with a wide array of ambients.

[warrtalon]

Lastly, as I've said before, forcing SAE is not good, because up at 6800' here in the Springs, the SAE CF is 1.32 at times, which is WAYYYYYYYYYYYYY too high for forced induction cars. SAE is ONLY for N/A cars, and that HAS to be considered. You don't notice the major difference at sea level, because there is no calculation for barometric pressure - just temps and humidity. But up here, we have a gigantic correction for the lack of atmospheric pressure that has been verified to only work for N/A cars. I dyno'd at sea level then at this altitude, and the SAE numbers up here were 40whp higher than actual...

 

This is correct. CFs don't work correctly on FI cars that effectively have internal atmospheres and benefit sometimes from the passive cooling effect of humidity. Now temp. DOES matter, and there must be someway to equalize readings in various parts of the country on different days with a wide array of ambients.

 

I don't know how it's possible when comparing across regions and such or when cars go from 6000' to sea level to race. You can incorporate the temp/humidity correction without the barometric correction if you are able to set the altitude manually, but I think most dynos use a weather station to automatically determine the CF.

[GAC]

Some scientist needs to come up with a good CF formula for FI cars and write some software. Simple as that.

[Greg G.]

To be honest, I'm mostly concerned with cars being equal at a given event, not across regions. So, if everyone in Colorado uses the same dyno, with the same CF issues, it doesn't really matter. When we go to Mid-Ohio, cars better be prepared for that elevation, etc. I hear what you are saying about FI vs. NA, but we don't have a better solution. So, "It is what it is."

[warrtalon]

To be honest, I'm mostly concerned with cars being equal at a given event, not across regions. So, if everyone in Colorado uses the same dyno, with the same CF issues, it doesn't really matter. When we go to Mid-Ohio, cars better be prepared for that elevation, etc. I hear what you are saying about FI vs. NA, but we don't have a better solution. So, "It is what it is."

 

Well, that's the thing - we don't use the same dyno, and the corrections aren't the same. Also, there is a 1000' elevation difference from Denver to Colorado Springs despite only being 60 miles apart. The Dyno Dynamics in the Springs uses a half correction factor for forced induction cars, and a full one for N/A cars, but the Dynojet up in Denver just spits out the huge, incredibly inflated numbers for forced induction cars, because it does not have the ability to modify the CF. What I'm getting at is that due to an incredibly inflated CF being applied to my power on that Dynojet, I'd get bumped just beyond the edge of TTS and into TTU (unless you let me use the Dyno Dynamics in my city - only AWD dyno in town), but anywhere else in the country, I'd easily be in TTS on any dyno .

[Greg G.]

We are going to allow the Dyno Dynamics dynamometer for AWD cars. However, the issue will be that if NASA elects to dyno a car, and only has one of the other dynos available, you (everyone) will have to be compliant on that dyno. It sounds like you may have that covered, but it will be up to you to make sure the car is legal.

[warrtalon]

We are going to allow the Dyno Dynamics dynamometer for AWD cars. However, the issue will be that if NASA elects to dyno a car, and only has one of the other dynos available, you (everyone) will have to be compliant on that dyno. It sounds like you may have that covered, but it will be up to you to make sure the car is legal.

 

Greg, that is excellent, and I will have no problem being dyno'd on other dynos in other regions/venues. Thank you!