New NASA Class for 2012: Spec Z
Joined: May 2002
Posts: 8,623
Likes: 1,392
From: Aurora, Colorado
I should be there 

Will any of you be going to the Road Atlanta event in December? I may have mentioned this before, but I can't remember. I am heavily considering coming down. I really want to try that track. Me and another member on here may come down and run all three days. I will still be in TTB, but either way, I would love to meet some of you guys.
Hey, For the guys with a good understanding of data analysis.
In longitudinal G figures, should a street car (like a Spec Z) post similar peak lateral numbers to peak longitudinal braking numbers? I'm remembering reading somewhere the they should be the same, but I'm not sure if that was an example of a car with a lot of aero or what not. Most of the traction circles I've seen of others leave braking about 85-90% of the lateral figure.
My undersanding says the graph should sharply transition to full force, very quickly, and then tail off gradually as steering lock is fed in.
In longitudinal G figures, should a street car (like a Spec Z) post similar peak lateral numbers to peak longitudinal braking numbers? I'm remembering reading somewhere the they should be the same, but I'm not sure if that was an example of a car with a lot of aero or what not. Most of the traction circles I've seen of others leave braking about 85-90% of the lateral figure.
My undersanding says the graph should sharply transition to full force, very quickly, and then tail off gradually as steering lock is fed in.
Thanks, filling out a racer app with them now.
I'm halfway through my build and I am holding off on buying a wavetrack because of the problems I have read about on here. Does anyone think that Nissan will realistically change the rules to accomodate other LSD's?
I'm halfway through my build and I am holding off on buying a wavetrack because of the problems I have read about on here. Does anyone think that Nissan will realistically change the rules to accomodate other LSD's?
Forgive me for typing this on a phone. Lateral G-Force is really a measure of traction, and traction is basically a measure of a tires grip. Theoretically the amount of G-Force measured should be the same in all directions. That does not mean that always happens in the real world or in real practice. There are very few times where car is able to accelerate with the same G forces that it's able to do side to side lateral Gs or braking deacceleration.
One measurement for good data analysis is the G force Circle, which most times is not a circle of more of an oval in shape with extensions on the left and the right into the bottom. a good measurement of how you're doing is to have a lot of data points on the fringes of that circle with larger openings called sinuses in the middle.
I hope this is the kind of answer you were looking for, if not feel free to ask more or p.m. me or email me with any other questions.
One measurement for good data analysis is the G force Circle, which most times is not a circle of more of an oval in shape with extensions on the left and the right into the bottom. a good measurement of how you're doing is to have a lot of data points on the fringes of that circle with larger openings called sinuses in the middle.
I hope this is the kind of answer you were looking for, if not feel free to ask more or p.m. me or email me with any other questions.
Hey, For the guys with a good understanding of data analysis.
In longitudinal G figures, should a street car (like a Spec Z) post similar peak lateral numbers to peak longitudinal braking numbers? I'm remembering reading somewhere the they should be the same, but I'm not sure if that was an example of a car with a lot of aero or what not. Most of the traction circles I've seen of others leave braking about 85-90% of the lateral figure.
My undersanding says the graph should sharply transition to full force, very quickly, and then tail off gradually as steering lock is fed in.
In longitudinal G figures, should a street car (like a Spec Z) post similar peak lateral numbers to peak longitudinal braking numbers? I'm remembering reading somewhere the they should be the same, but I'm not sure if that was an example of a car with a lot of aero or what not. Most of the traction circles I've seen of others leave braking about 85-90% of the lateral figure.
My undersanding says the graph should sharply transition to full force, very quickly, and then tail off gradually as steering lock is fed in.
Last edited by mhoward1; Aug 1, 2012 at 06:00 PM. Reason: Siri really screwed that up
Good plan...don't buy a Wavetrac untill you are ready to race in Spec Z...
And No, I don't think Nissan is gonna change the rules...in fact i understand they are gonna start sellling a Diff Cooler to address the heat issues...
And you have to run Motul @ $35 a Liter...
And No, I don't think Nissan is gonna change the rules...in fact i understand they are gonna start sellling a Diff Cooler to address the heat issues...
And you have to run Motul @ $35 a Liter...
I have a 91 and 100 octane program on my UpRev. Problem is that you switch maps with the cruise control. . . which I no longer have since I have a removable steering wheel. I'll have to ask UpRev how guys with base model Zs do multiple tunes. Any know by chance though?
I have a 91 and 100 octane program on my UpRev. Problem is that you switch maps with the cruise control. . . which I no longer have since I have a removable steering wheel. I'll have to ask UpRev how guys with base model Zs do multiple tunes. Any know by chance though?
ONLY A OEM ECU must be used, but it can be "flashed"....no aftermarket or "piggy-back" systems are allowed
12.9 ECU
a) Factory ECU must be retained. Replacement or “piggy back” systems are not permitted.
“Reflashing” of factory ECU is permitted. Refer to Appendix A for recommended Nissan Part.
12.9 ECU
a) Factory ECU must be retained. Replacement or “piggy back” systems are not permitted.
“Reflashing” of factory ECU is permitted. Refer to Appendix A for recommended Nissan Part.
ONLY A OEM ECU must be used, but it can be "flashed"....no aftermarket or "piggy-back" systems are allowed
12.9 ECU
a) Factory ECU must be retained. Replacement or “piggy back” systems are not permitted.
“Reflashing” of factory ECU is permitted. Refer to Appendix A for recommended Nissan Part.
12.9 ECU
a) Factory ECU must be retained. Replacement or “piggy back” systems are not permitted.
“Reflashing” of factory ECU is permitted. Refer to Appendix A for recommended Nissan Part.
How about skip welding on critical areas of the chassis? I know the general rule is "If the rules don't say it is legal, it's not", but swapping body parts with a NISMO is legal, and the NISMO is seam welded.
I have not seen a "formal" answer to the question...that one needs to go to National to answer...I will send an email and see if I can get feedback.
My personal feeling is that it is legal...but don't go do nothin' crazy yet...
My personal feeling is that it is legal...but don't go do nothin' crazy yet...

Thanks, missed that when looking at the rules. Might be time for an eye exam 
How about skip welding on critical areas of the chassis? I know the general rule is "If the rules don't say it is legal, it's not", but swapping body parts with a NISMO is legal, and the NISMO is seam welded.
How about skip welding on critical areas of the chassis? I know the general rule is "If the rules don't say it is legal, it's not", but swapping body parts with a NISMO is legal, and the NISMO is seam welded.
Car looks great!
Joined: May 2002
Posts: 8,623
Likes: 1,392
From: Aurora, Colorado
Thanks, missed that when looking at the rules. Might be time for an eye exam 
How about skip welding on critical areas of the chassis? I know the general rule is "If the rules don't say it is legal, it's not", but swapping body parts with a NISMO is legal, and the NISMO is seam welded.
How about skip welding on critical areas of the chassis? I know the general rule is "If the rules don't say it is legal, it's not", but swapping body parts with a NISMO is legal, and the NISMO is seam welded.
IMHO skip or seam welding is NOT allowed and shouldn't be if we're trying to build a class with limited modifications. Everytime the rules get amended to allow more changes, the motivation DROPS for someone to start building their own Spec Z.









and Spec Z