Yep... 4th should be specified. Full throttle, 2000RPM - fuel cutRPM also should be in there.

As a practical matter, how will oil temp be determined, especially for cars with no oil temp gauge? I am not aware of a dyno with oil temp sensors or how they would/could be used.

While this rule is a "done deal", folks should be aware that it will require more than one dyno, per season, for anyone that is close or at the 138 cap. Anytime a dyno is at a track, it will necessitate all of those at or near the cap to go to that dyno to confirm their numbers ON THAT DYNO! That means that anyone that goes to Nationals, and is close, will have to book time on THAT dyno and that dyno was busy last time, at Miller, and will be even busier this time because of this rule. As I have mentioned, and was documented at Nationals at Miller, that dyno gave significantly different numbers over a number of runs on my car during the course of four days. NASA has the exact data, I do not. I was dynoed in GTS as well as 944-Spec. If that dyno gives inconsistent results, again, then what happens?? Remember, the scales that NASA uses at tracks are notorious for being inaccurate, sometimes as much as 30+ pounds different and I have personal experience with the Nationals dyno being variable.

Perhaps there should be a way to have dyno runs done and the engine "sealed" so it does not require any additional dyno time as long as the engine seals are intact. This would seem to be a logical and fair solution for all and solve any issue of dyno inconsistency.

Just sharing my experience with the dyno at Nationals and, therefor, my concern.

I know of many stories about dyno DQ after a Nats race at Miller in 09-10. Most of these guys spent lots of money at Nats on the dyno making sure they were not over.

My car measured a few HP different each time as well. At that time there was no HP cap so it was not an issue in 944 but since I was running GTS as well i had to make sure I was within my HP to Weight catagorie. It came in pretty close after the race.

Eric did you guys use the portable dyno at Nats? Was it the me one as at Miller? Was there a HP variation that you saw at Nats?

Easy now, Big Dog - that level of anxiety is a little unbecoming!

It is a sad truth at Miller, that most all cars coming up there from sea level are going to be significantly out of tune, and need dyno testing to be at their very best, cap or no. Sealing your motor at sea level would be a bad idea, and impractical. Dyno time can be reserved ahead of time - maybe we could get a block for 944 Spec.

I had a whole big paragraph about our years of experience with that dyno run (by Backstreet), but I'll spare everyone a rehash, We haven't seen cars suddenly make more HP & fall out with that dyno. And yes, that mobile dyno is the one that was at Nationals (MIller & MId-O). Go by the highest number your car made on the dyno at Nationals - that is your car is capable of. If you got the car all warm & in tune, and set the pressures, it will make similar numbers again. If you hop on the dyno cold, and with unknown tire pressures, it won't - that's your big dyno variation. Give yourself a little headroom, just like with weight. We are going to make sure the cars are warm going on the dyno, and do a practice pull, or two 1st, until the HP stabilizes.

Oil temps can be measured by an infrared pyrometer on the oil cooler.
4th gear is 1:1, so yes, we'll add that to the procedure, and it is how all the testing was done. We should Spec the rev limit as well - we already caught one aftermarket chip with that this year. Thanks for the suggestions.

I know that at Miller, there was no consistency regarding tire pressures. In fact, we were not allowed to touch the tires to even take tire pressures. The stated reason was that we might try to lower tire pressures. Of course, I have no idea what the tire pressures were for each run and, if they can make a significant difference, that could be the reason for differences I saw at Miller with my own car. I also do not know what the oil temps were for each of the various dyno runs as they were not checked by the dyno operator. Perhaps those are the reasons for the significant differences my car saw, reasons I had no idea about. You can be sure that I will be much more involved in the process of the dyno knowing what has been shared here.

Perhaps you misunderstood the suggestion for sealing an engine. My suggestion was not to do it wherever, it was to do it at Miller, after a dyno session, and be done with it. It still seems like a good idea.

My bigger point, for the class, is that, IMO, it will certainly add significant cost for many of our group to ensure we are not DQ'ed at Miller and other places as well. Just like we go to the official scales at the track each day, to be sure the scales did not go whacky as they have been known to do, with 30+ pound variations, those that are close will need to go to the dyno more than once a season to be sure they are, and remain, OK.

In addition, we will have costs to be prepared, whether it is with different oil, restrictors or whatever, to respond if the dyno shows a problem in order to reduce power and then the cost to re-dyno the car to be sure of the change. Unless guys have restrictors made in advance, trying to make them at Nationals will be a nightmare.

The total cost to our group will surely be significant, collectively, and should not be minimized. Unlike you, Eric, I do not have ANY confidence that all of the "approved" brand/model dyno's across the country are going to give identical, or even close, numbers. I hope I am wrong. My experience has been that each one has a different state of repair and maintenance. I do know that the one you keep referring to, that was used at Miller and Ohio, was criticized, including maintenance questions, by many, for many reasons, when it was at Miller and I know that I would not be comfortable using the results of the dyno at Buttonwillow for compliance at Miller. That means, at a minimum, two dyno sessions next year, if not three, and I would guess that many others will be faced with the same expense of both multiple dyno sessions and spare parts in order to address any potential issues that might come up and it should not be sugar coated for those that will incur those expenses.

By the way, none of this was intended to be negative and I hope no one takes it that way. Rather, it was intended to share thoughts and ideas for the betterment of the class as we all need to be aware of what we are being required to do and need to be properly prepared for it.

Miller will be awesome next year. 30+ 944's going into turn one, six wide, is an experience everyone should have so make plans now for the true, National 944 championship races.

Thanks Big Dog, and I do appreciate your concerns. People do get DQ'd on the dyno, and it takes some villigence to ensure you don't. That is going to cost the top guys who area close to the limit some money. Running at the pointy end of the field always does. For the class as a whole, though, approaching the cap is less expensive than it was. I personally know of many who built new motors, just to compete, not because their old motor was even very tired. Those that couldn't had a significant handicap, that has now become a lot smaller. Dyno are peanuts in comparison - hundreds instead of thousands, even over the course of years.

It occurred to me that we are looking at this somewhat backwards. Intertial dynos are pretty simple machines. They have a heavy roller, that is a consistant weight from one dyno to the next. It takes a certain amount of power to spin that roller up to a given HP. If a car make 144 HP, the dyno didn't make that up - that motor did that at that point. The key is getting a given motor to show it's true potential, and this is where people get caught out. If racers don't pay attention to the details of optimizing their test runs, than they will get a false sense of security. Even then, to fall out, a motor still has to have the potential to make over (140 HP + 140 TQ)/2, which only a few do. Racers can fall out for three reasons:

1) Didn't test a strong motor well enough (or at all) to find it's true potential, and restrict it.
2) Left themselves too little headroom in detuning, or used an unreliable means of detuning.
3) Knew they were making too much HP, and hoped they wouldn't be caught.

We have given a path to get to #1.
We all have to develop our own comfort level for what #2 means, based on our perception of what actual dyno variation remains. If you feel it's 5 HP, tune your car appropriately. We all make this calculation in weight all the time. When we are wrong, we tend to want to blame the the equipment! The third place car this year at Nationals weighed 2601lbs (!). One more lap would had have him DQ'd. He cut that pretty close. The rest of us left a little more cushion. It's a judgement call. One difference is that most cars can go under weight, and most can't reach over 140 (the hard cap).

In the end for whatever pain this has, or will cause, I am sorry. But the momentum that it has already created for Nationals is very exciting. Like you, I can't wait!