Inspection and Testing

[GlennCMC70]

From the CMC rules:
3.10 Inspection and Testing
NASA tech inspectors and CMC Officials have the right to inspect anything in sight at any time the car is at the track. NASA tech inspectors and CMC Officials have the right to request disassembly or any other procedure required to verify car compliance with these rules including a dynamometer re-certification. CMC Officials may require that a CMC Official or designee be present for any dynamometer re-certification.

So a question was asked in another thread about concerns over placing a car on a dyno other than the one used to certify that car for the season. The above rules indicate that anyone can be checked at any point of the season. The tools used at the track are considered Official. You may be allowed to provide your tools to measure with if found out of compliance.
One thing to keep in mind. It is you who decides how close to the limit you will go. The published limits are not a required number, but rather a limit. Lots of folks will allow a little wiggle room, and other will not. The risk is yours.

[Suck fumes]

Ill just make sure to eat two cheeseburgers to put some weight on my ass before the race lol!

[GlennCMC70]

I know that w/ your SPEC Miata background that this is something you haven't had to deal w/ (in regards to dyno checks) since that class has no HP limits (F'ing stupid if you ask me - 99% the cause of that class being so $$$$). Normally you will see as much variance from the same dyno from pull to pull as you will from dyno to dyno. If you push the limits, you will at some point break out.
Here is a couple ways you can get into trouble....
1) You have your car set to make 267hp and 317tq (max allowed hp/tq numbers no matter the car's weight). If you make 268hp and 317tq, your DQ'ed. If you make 267hp and 318tq, your DQ'ed. You decided to max the numbers and you take the risk of breaking out. Safer numbers would be 260hp/310tq. This gives you max room in case you needit (as long as you havethe correct weight to go along w/ it.

2) You have your car set to 260hp and 310tq (for a LT1 4th gen). You have your car set-up to come off track right at 3250lbs (platform minimum weight). When checked you come off at 3249lbs. Yor DQ'ed. Even if your power numbers were 255hp/305tq, your still DQ'ed. Or you have the car at 260hp and 310tq and your post race weight is 3250lbs on the nose. But we pull you for a random dyno. On the dyno you make 1 more HP or TQ than your dyno sheet makes - your DQ'ed.

The leason in all this???? Push it as close as you want. How willing are you to get a DQ and end your chance at a season Championship is up to you. These type of DQ's are not droppable. They end a season points run.

If you ask me, 255hp and 305tq w/ a post race weight of 3260lbs (4th gen again) - is about as close as anyone needs to be. It gives you 5 hp and 5 tq wiggle room and 10lbs of margin. On our scales, even 10lbs is too close. In the past few years I was coming off the scales 50lbs over. That and my car was certed 5hp low. In our class, 5-10 hp ain't gonna hurt anything and 20-30lbs will go un-noticed. The cars are just to sloppy for it to matter that much. And the numbers are peak numbers. Over the average, this really doesn't matter too much.

And let this past weekend show how serious we are this year. We handed our more DQ's this past event then all of 2012.

[marshall_mosty]

On the dyno sheet, it dictates that the Dyno will correct to standard temp, humidity, and pressure. As long as you aren't in crazy elevation (which we aren't), each dyno should read the same.

Always give yourself a margin on being overweight. I was pulled at TWS a few years back and that dyno read a little high and my minimum weight ended up at 1/4 of 1 pound less than what I scaled... Yes, I was literally a fart away from being underweight, but just squeaked by.. I always like to come in 40-50 lbs heavy.

[kbrewmr2]

this "leave yourself a little wiggle room" applies to really ANY NASA class that uses dyno testing. GTS, ST, etc, etc, etc. Not many people really "get it" though...

[Crumpacker]

[I] pulled 260/287 after the races at Houston (sunny and mid-60's temp). I came off track 25 lbs. over minimum weight so technically I had room to pull 262 hp and still be legal.

This brings up a question.

Let's say my sn95 mustang has 260/290 on the sticker, which means my min weight is 3150 (also listed on the sticker). The tech official checks my weight based on a 3150 minimum and I pass by a few pounds in each of the first 3 races. After R4, I'm selected for random dyno and pull a 263 - but I happen to be 40lbs over weight for that race (which is okay for 263hp)... I'm still legal?

I haven't looked at the rulebook, but I was under the impression you could only dyno up to 260 if your sticker showed anything under that because your min weight is being checked against a 260hp car.

[ShadowBolt]

This brings up a question.

Let's say my sn95 mustang has 260/290 on the sticker, which means my min weight is 3150 (also listed on the sticker). The tech official checks my weight based on a 3150 minimum and I pass by a few pounds in each of the first 3 races. After R4, I'm selected for random dyno and pull a 263 - but I happen to be 40lbs over weight for that race (which is okay for 263hp)... I'm still legal?

I haven't looked at the rulebook, but I was under the impression you could only dyno up to 260 if your sticker showed anything under that because your min weight is being checked against a 260hp car.

If I understand it correctly if you pulled 263 and had the extra weight to cover the extra 3 HP you would be okay. Yes/NO?


JJ

[Suck fumes]

Here's my concern, whether it be NASA or SCCA, their scales are never consistent! I remember last year I weighed before a race and was 30 Pds overweight then after the race I weighed only 5 pds lighter. Now I know I burned 4 gallons of gas which is roughly 25pds! Plus I've also noticed that scales fluctuate based on temp change as well so I just don't see how this whole Dyno/weight thing could be that accurate with so many variables.

[Rob Liebbe]

Here's my concern, whether it be NASA or SCCA, their scales are never consistent! I remember last year I weighed before a race and was 30 Pds overweight then after the race I weighed only 5 pds lighter. Now I know I burned 4 gallons of gas which is roughly 25pds! Plus I've also noticed that scales fluctuate based on temp change as well so I just don't see how this whole Dyno/weight thing could be that accurate with so many variables.

That is why you don't cut weight and power too close. Also, at least with NASA, you can re-weigh if there is a question about your results. I've seen cars be pushed off the scales and back on so long as it doesn't leave sight of the tech inspectors.

[GlennCMC70]

If I understand it correctly if you pulled 263 and had the extra weight to cover the extra 3 HP you would be okay. Yes/NO?


JJ

Yes - legal. And it would be the weight recorded at the time of dyno selection.