How to deal with new NASA TT and ST AVG HP rules
12-14-2017, 03:14 PM
#32
Kevin - can you post your dyno curve. If shape is same as mine then I agree it's unfair but doubt that rule will change this year. If the SC with proper tune can keep your power flat in low to mid range then I think you will still be competitive.
I tried to upgrade cams at beginning of year which gave me more peak power but did nothing to increase mid range power. I had to add 145 pounds to offset the peak power increase even with avg hp calcs. Since I still spend majority of time between 5 and 7 k there was no real benefit from peak increase and a clear drop due to weight.
I went back to stock cams and my old weight and like that setup better.
I tried to upgrade cams at beginning of year which gave me more peak power but did nothing to increase mid range power. I had to add 145 pounds to offset the peak power increase even with avg hp calcs. Since I still spend majority of time between 5 and 7 k there was no real benefit from peak increase and a clear drop due to weight.
I went back to stock cams and my old weight and like that setup better.
12-14-2017, 04:43 PM
#33
Rennlist Member
There are two reasons that this might be more fair:
1. generally, most high hp , high reving cars have closer gear ratios to lessen the disadvantage of the narrow HP band. if you dont have 70% of your RPM after a redline shift and have more like 77 to 85% of your redline RPM, you are close ratio.
2. most higher reving engines are mated to lighter cars, because the engines themselves are lighter. this means they have a natural "absolute" weight advantage which effects braking and cornering.
Let me know what i might be missing.
keep in mind that everyone's hp value for the class will go up, unless you have a flat HP curve, like a cayman GT4 , in which case it probably didnt get effected by narrower RPM measurements. did this narrowing of the data point band go up for only turbocars?? if so, that might be a little unfair for them compared to a equal shape NA engine at the same power.
12-14-2017, 05:38 PM
#35
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ok so i get it.. there is a narrower frequency for the 4 or so HP measurment points, so it artifically raises your average vs having the peaky HP and wider averaging data points. is that the problem?
There are two reasons that this might be more fair:
1. generally, most high hp , high reving cars have closer gear ratios to lessen the disadvantage of the narrow HP band. if you dont have 70% of your RPM after a redline shift and have more like 77 to 85% of your redline RPM, you are close ratio.
2. most higher reving engines are mated to lighter cars, because the engines themselves are lighter. this means they have a natural "absolute" weight advantage which effects braking and cornering.
Let me know what i might be missing.
keep in mind that everyone's hp value for the class will go up, unless you have a flat HP curve, like a cayman GT4 , in which case it probably didnt get effected by narrower RPM measurements. did this narrowing of the data point band go up for only turbocars?? if so, that might be a little unfair for them compared to a equal shape NA engine at the same power.
There are two reasons that this might be more fair:
1. generally, most high hp , high reving cars have closer gear ratios to lessen the disadvantage of the narrow HP band. if you dont have 70% of your RPM after a redline shift and have more like 77 to 85% of your redline RPM, you are close ratio.
2. most higher reving engines are mated to lighter cars, because the engines themselves are lighter. this means they have a natural "absolute" weight advantage which effects braking and cornering.
Let me know what i might be missing.
keep in mind that everyone's hp value for the class will go up, unless you have a flat HP curve, like a cayman GT4 , in which case it probably didnt get effected by narrower RPM measurements. did this narrowing of the data point band go up for only turbocars?? if so, that might be a little unfair for them compared to a equal shape NA engine at the same power.
nevermind dude.
12-14-2017, 06:56 PM
#37
12-14-2017, 08:03 PM
#38
Rennlist Member
it was more addition by subtraction. Everyone got a bit of a penalty because they narrowed the data selection ranges from every 500 rpm to every 250 rpm. They then pretty much nullified everyone but turbo cars penalty by giving all the other cars 6 or 8 rpm data points instead of the old standard 4. For example my turbo car was at 538 whp with the old method. Now it' at 550. If it were at the new method but 8 rpm points it would Have actually reduced to 536 and at 6 rpm points would have only slightly bumped to 542. There is no need for this in ST1-3 as once you get to bigger turbos and V8's any power curve advantage is offset by throttle reponse and some. It doesn' make any sense but is what I've come to expect from NASA. Advantage corvettes.
e.
e.
12-14-2017, 08:09 PM
#39
Rennlist Member
Kevin - can you post your dyno curve. If shape is same as mine then I agree it's unfair but doubt that rule will change this year. If the SC with proper tune can keep your power flat in low to mid range then I think you will still be competitive.
I tried to upgrade cams at beginning of year which gave me more peak power but did nothing to increase mid range power. I had to add 145 pounds to offset the peak power increase even with avg hp calcs. Since I still spend majority of time between 5 and 7 k there was no real benefit from peak increase and a clear drop due to weight.
I went back to stock cams and my old weight and like that setup better.
I tried to upgrade cams at beginning of year which gave me more peak power but did nothing to increase mid range power. I had to add 145 pounds to offset the peak power increase even with avg hp calcs. Since I still spend majority of time between 5 and 7 k there was no real benefit from peak increase and a clear drop due to weight.
I went back to stock cams and my old weight and like that setup better.
12-15-2017, 12:07 AM
#44
Rennlist Member
