TT NASA reclassed, Too much HP |
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TT NASA reclassed, Too much HP |
Jetsetsurfshop |
Oct 23 2017, 03:08 PM
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#1
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Senior Member Group: Members Posts: 814 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States |
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jd74914 |
Oct 24 2017, 08:42 AM
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#2
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Its alive Group: Members Posts: 4,780 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
That is a pretty nice curve!
One question though...Do you have to dyno on a DynoJet inertial dyno for NASA classification? I bet if you reran on an eddy brake (like a Mustang, etc.) you'd see ~15% less power. Not sure if that would help your classing but just something to think about. Inertia dyno's calculate power by measuring acceleration rates of the drum. They assume a drive line inertia, probably much higher than that of a Type4 motor/914 trans/small wheels because most motor/trans/wheel packages are much higher inertia, which will result in a higher engine power reading than is correct. Edit: Some DynoJets also have eddy brakes, so you'd have to check which kind your shop uses. Just trying to help out with your classing if possible; it seems rather unfair. |
Jetsetsurfshop |
Oct 24 2017, 05:58 PM
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#3
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Senior Member Group: Members Posts: 814 Joined: 7-April 11 From: Marco Island Florida Member No.: 12,907 Region Association: South East States |
That is a pretty nice curve! One question though...Do you have to dyno on a DynoJet inertial dyno for NASA classification? I bet if you reran on an eddy brake (like a Mustang, etc.) you'd see ~15% less power. Not sure if that would help your classing but just something to think about. Inertia dyno's calculate power by measuring acceleration rates of the drum. They assume a drive line inertia, probably much higher than that of a Type4 motor/914 trans/small wheels because most motor/trans/wheel packages are much higher inertia, which will result in a higher engine power reading than is correct. Edit: Some DynoJets also have eddy brakes, so you'd have to check which kind your shop uses. Just trying to help out with your classing if possible; it seems rather unfair. NASA only accepts the Dynojet, no Mustang dyno pulls. I don't believe that my car makes 160hp. I wonder what my face looked like in front of my peers when he said 160hp. I bet my mouth was on the floor. It was hard to dispute the numbers to the group when the three spec miatas in front of me and the two cars after me pulled what they expected on the same dyno. Like I said, I dont believe it. I did do my best time ever though. 2:39.8. Three seconds slower that a supercharged Miata with 225/45 on 9 inch rims. |
jd74914 |
Oct 24 2017, 10:47 PM
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#4
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Its alive Group: Members Posts: 4,780 Joined: 16-February 04 From: CT Member No.: 1,659 Region Association: North East States |
NASA only accepts the Dynojet, no Mustang dyno pulls. I don't believe that my car makes 160hp. I wonder what my face looked like in front of my peers when he said 160hp. I bet my mouth was on the floor. It was hard to dispute the numbers to the group when the three spec miatas in front of me and the two cars after me pulled what they expected on the same dyno. Like I said, I dont believe it. I did do my best time ever though. 2:39.8. Three seconds slower that a supercharged Miata with 225/45 on 9 inch rims. That's disappointing. Unfortunately, the operator can play a huge role in indicated power. The rate they ramp or correction constants can really affect the final output. Best time ever is awesome though, congrats! |
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