Adventures in PTE/TTE
#443
All the "shitty" stuff that bugs everyone doesn't bother me. Greg has always been nice to me and I've been nice back.
NASA is fun to race with when you aren't spending gobs of money and worrying about winning the whole time. You west coast guys have MC, us mid-western/East coasters have nothing but NASA. Ill keep running with NASA as long as my friends run with NASA.
NASA is fun to race with when you aren't spending gobs of money and worrying about winning the whole time. You west coast guys have MC, us mid-western/East coasters have nothing but NASA. Ill keep running with NASA as long as my friends run with NASA.
#445
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All the "shitty" stuff that bugs everyone doesn't bother me. Greg has always been nice to me and I've been nice back.
NASA is fun to race with when you aren't spending gobs of money and worrying about winning the whole time. You west coast guys have MC, us mid-western/East coasters have nothing but NASA. Ill keep running with NASA as long as my friends run with NASA.
NASA is fun to race with when you aren't spending gobs of money and worrying about winning the whole time. You west coast guys have MC, us mid-western/East coasters have nothing but NASA. Ill keep running with NASA as long as my friends run with NASA.
#446
So, everyone is discussing these high hp heavy weight reclasses and suggesting they will be faster. I really don't think that's the case. This seemed to have started after a heavy car won east nats last year, 2800lb (I think) rx7. The rx7 had a lot of straight speed, but that's cause it was making class power to weight on the points system, which will always be more hp than a dyno reclass for a decent handling car. Additionally with the points system, you get an extra hp mod factor for being heavy - you don't get that benefit with a heavy dyno reclass.
In other words, if a miata dyno reclassed to PTE* at 2800lbs, it's still going to be 17.3:1 ish power to weight ratio and allowed to make up to 162 whp . A 2800lb points based car with modifiers can make 16.1:1 ratio, making up to 174 whp. Thus, the benefit to being heavy only really applies to points based cars, and a points based miata will never make enough hp to run at class power to weight ratio above say 2500 lbs. Simply not gonna happen without giving up points for a proper suspension and good tires.
Just my two cents before people run out at spend time and money trying to make their cars weigh 2600 pounds.
In other words, if a miata dyno reclassed to PTE* at 2800lbs, it's still going to be 17.3:1 ish power to weight ratio and allowed to make up to 162 whp . A 2800lb points based car with modifiers can make 16.1:1 ratio, making up to 174 whp. Thus, the benefit to being heavy only really applies to points based cars, and a points based miata will never make enough hp to run at class power to weight ratio above say 2500 lbs. Simply not gonna happen without giving up points for a proper suspension and good tires.
Just my two cents before people run out at spend time and money trying to make their cars weigh 2600 pounds.
#449
And on your other point, my impression was that Greg looks at area under the curve as a factor when assigning weight when he gives a dyno reclass anyway?
#450
<p>
</p><p> </p><p>Why would points based cars have any more or less advantage than dyno-reclass when heavier? The heavier car suggestion is for a dyno-reclass only anyway, because you won't make your p:w limit otherwise. </p><p> </p><p>
</p><p> </p><p>I think he is looking at VVT vs. non-VVT. You might be right, but I haven't seen enough indicators from him or the rules that he is doing that on a broad scale.</p>
So, everyone is discussing these high hp heavy weight reclasses and suggesting they will be faster. I really don't think that's the case. This seemed to have started after a heavy car won east nats last year, 2800lb (I think) rx7. The rx7 had a lot of straight speed, but that's cause it was making class power to weight on the points system, which will always be more hp than a dyno reclass for a decent handling car. Additionally with the points system, you get an extra hp mod factor for being heavy - you don't get that benefit with a heavy dyno reclass. In other words, if a miata dyno reclassed to PTE* at 2800lbs, it's still going to be 17.3:1 ish power to weight ratio and allowed to make up to 162 whp . A 2800lb points based car with modifiers can make 16.1:1 ratio, making up to 174 whp. <strong>Thus, the benefit to being heavy only really applies to points based cars,</strong> and a points based miata will never make enough hp to run at class power to weight ratio above say 2500 lbs. Simply not gonna happen without giving up points for a proper suspension and good tires. Just my two cents before people run out at spend time and money trying to make their cars weigh 2600 pounds.
If two cars with identical power to weight ratios and aerodynamics are traveling at 80 mph, which one will accelerate faster? The one with less weight and power, or the one with more weight and power? And on your other point, my impression was that Greg looks at area under the curve as a factor when assigning weight when he gives a dyno reclass anyway?
#451
A dyno reclassed Miata will never be at the weight to hp limit for the class, it will never happen. Theoretically, on points it is possible to be at the limit. When classed on points, there is a table that has a weight to hp modifier based on the competition weight. The modifier gets worse the lighter the car is, so a heavier car will have less of a weight to hp penalty. Every 50lbs below 3200lbs cost you 0.05 in weight to hp. So, all other things being equal a car weighing 2600lbs could be at 17.15 to 1, while a 2400lb car would be at maxed at 17.35 to 1, for PTE. So, the 2600lb car could have 151whp and the 2400lb car would be limited to 138whp for PTE. Which one will be faster, no idea, probably depends on the track.
#453
Mike is right. The points based car has a bigger advantage because the weight modifier table gives a better power:weight ratio for every 50lbs added. The dyno reclass car has a fixed ratio of about 18.1:1 for E and 17.1:1 for E*.
I don't think Andrew's argument has anything to do with the modifier table though. I think he's just saying that HP is king and everyone should be running super heavy so they can run more power.
I don't think Andrew's argument has anything to do with the modifier table though. I think he's just saying that HP is king and everyone should be running super heavy so they can run more power.
#454
Here is recent dyno reclass for a heavier Miata, 91 with a 99 swap. 2500lbs at 136whp for PTE. Ratio is 18.38 to 1, no where near the class limit. The same car on points at 2500 would be allowed to run 152whp but there would be no way to get a 1.6 to that power level with the same suspension, tires and aero.
#455
The problem is exactly as Jason stated, no matter how heavy you make the car you will never get to the class limit on a dyno reclass. On points it is theoretically possible but not practical as you have to give up suspension points for engine mods.
Here is recent dyno reclass for a heavier Miata, 91 with a 99 swap. 2500lbs at 136whp for PTE. Ratio is 18.38 to 1, no where near the class limit. The same car on points at 2500 would be allowed to run 152whp but there would be no way to get a 1.6 to that power level with the same suspension, tires and aero.
Here is recent dyno reclass for a heavier Miata, 91 with a 99 swap. 2500lbs at 136whp for PTE. Ratio is 18.38 to 1, no where near the class limit. The same car on points at 2500 would be allowed to run 152whp but there would be no way to get a 1.6 to that power level with the same suspension, tires and aero.
No one is saying he's wrong. But there has been consensus on that issue since 2013(?) so I'm not sure why it's relevant in a discussion about making dyno classed cars heavier.
#456
The problem is exactly as Jason stated, no matter how heavy you make the car you will never get to the class limit on a dyno reclass. On points it is theoretically possible but not practical as you have to give up suspension points for engine mods.
Here is recent dyno reclass for a heavier Miata, 91 with a 99 swap. 2500lbs at 136whp for PTE. Ratio is 18.38 to 1, no where near the class limit. The same car on points at 2500 would be allowed to run 152whp but there would be no way to get a 1.6 to that power level with the same suspension, tires and aero.
Here is recent dyno reclass for a heavier Miata, 91 with a 99 swap. 2500lbs at 136whp for PTE. Ratio is 18.38 to 1, no where near the class limit. The same car on points at 2500 would be allowed to run 152whp but there would be no way to get a 1.6 to that power level with the same suspension, tires and aero.
There is a very real point of crossover where a heavy 17.x PTE* reclass car will be faster than a lighter 16.x points car. If you assume similar shaped power curves, which I think is realistic, you can assume constant horsepower and calculate it.
There are also, obviously, cases where the points car will be better - if you can make the power to get there depends on what your starting point is. Everyone already knew that.