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2020+ Shelby GT500 Mustang
It's Official! 2020 GT500 Makes 760HP
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<blockquote data-quote="tt335ci03cobra" data-source="post: 16266672" data-attributes="member: 68944"><p>I assume you realize you posted an article with a nova that has:</p><p></p><p>“</p><p>With a 9-inch rearend housing, 3.73 gears, a Powerglide trans, and a 3,500-stall converter spinning BFGoodrich drag radials set at 30 psi, the driveline was as common as anything else.”</p><p></p><p>I assume you don’t comprehend much of the article you posted. You should re read it because if more than validates everything I’ve claimed.</p><p></p><p>So let’s play with what you’ve presented. That drivetrain ensemble ate up ~125tq based on comparing 3 different sae protocols. The difference largely comes from:</p><p></p><p>I read the article. The eddy wheel hub dyno corrected down to 487whp because it was assuming there were no accessories being spun by the engine. Gross hp. Think 1970’s. Keep in mind the engine is using 35-40tq to spin it’s serpentine belt and accessories at 6000rpm. That means 45hp right there, and they admit the temps and humidity varied. It would have shown about 535whp. It was hotter, and we don’t know the temp the dyno corrects to with that rating. The torque is added back in because it’s being accounted out from the bottom up. </p><p></p><p>Next the 564whp number was corrected to 77°f meanwhile the 675hp engine rating was corrected to 60°f and GROSS HP. The torque must be reduced because the torque is being added in from the top down. Meaning it reads about 40tq higher in this case. So apart from over correcting because it was 17° colder in the settings, it also is adding in the gross values. </p><p></p><p>So that 675hp engine would be realistically a 625hp engine at 6000rpm. 40tq at 6k is 45hp. 675-45=630. I’m going to be nice and say 17° is only worth 5hp. It’s honestly about 8.5hp at this juncture.</p><p></p><p>Now on to the comparison, what do we find...</p><p></p><p>564whp from the Dynojet becoming 630hp is a 66hp (57tq) loss at 6000rpm. That is very fitting of this type of setup. </p><p></p><p>Somethings you also should consider...</p><p></p><p>The % suggestions state that:</p><p></p><p>FF and RR lose 8-10%</p><p>Mr and fr lose 10-15%</p><p>Awd loses about 15-18%</p><p>4wd loses about 18-25%.</p><p></p><p>All manuals.</p><p></p><p>Autos lose an addition 5% in the guessing game. So in this case, an auto fr car should lose 20%. Even using the craptastic numbers they presented of 564whp and 675hp, we see 16% loss, which doesn’t stand up to the % game.</p><p></p><p></p><p></p><p></p><p></p><p></p><p>Look, let me explain it to you like this, does an alternator, water pump, oil pump, and so on eat up gradually more tq just because the engine gets a pair of headers and a supercharger bolted on? Assume rpm doesn’t change, you might be spinning the oil pump a little harder, or the alternator a little harder to supply electricity for the fuel pump, but you don’t just assume you have an extra 25% more parasitic drag on the serpentine assembly because you add 25% more hp.</p><p></p><p></p><p></p><p>If you take a 20lbs drive shaft, and hook it up to a thrust dyno, then measure the force needed to spin it to 6,000rpm, its resistance to spin won’t read any differently if you then slowly accelerate it to 6000rpm to represent 300tq, or very quickly accelerate it to 6000rpm to represent 900tq. </p><p></p><p></p><p>Torque is being produced by the engine, and reaches the wheels after driving the drivetrain. The drivetrain is made out of metal and carbon fiber and alloys. None of those materials are spunge like globs of gum or honey that sap away torque.</p></blockquote><p></p>
[QUOTE="tt335ci03cobra, post: 16266672, member: 68944"] I assume you realize you posted an article with a nova that has: “ With a 9-inch rearend housing, 3.73 gears, a Powerglide trans, and a 3,500-stall converter spinning BFGoodrich drag radials set at 30 psi, the driveline was as common as anything else.” I assume you don’t comprehend much of the article you posted. You should re read it because if more than validates everything I’ve claimed. So let’s play with what you’ve presented. That drivetrain ensemble ate up ~125tq based on comparing 3 different sae protocols. The difference largely comes from: I read the article. The eddy wheel hub dyno corrected down to 487whp because it was assuming there were no accessories being spun by the engine. Gross hp. Think 1970’s. Keep in mind the engine is using 35-40tq to spin it’s serpentine belt and accessories at 6000rpm. That means 45hp right there, and they admit the temps and humidity varied. It would have shown about 535whp. It was hotter, and we don’t know the temp the dyno corrects to with that rating. The torque is added back in because it’s being accounted out from the bottom up. Next the 564whp number was corrected to 77°f meanwhile the 675hp engine rating was corrected to 60°f and GROSS HP. The torque must be reduced because the torque is being added in from the top down. Meaning it reads about 40tq higher in this case. So apart from over correcting because it was 17° colder in the settings, it also is adding in the gross values. So that 675hp engine would be realistically a 625hp engine at 6000rpm. 40tq at 6k is 45hp. 675-45=630. I’m going to be nice and say 17° is only worth 5hp. It’s honestly about 8.5hp at this juncture. Now on to the comparison, what do we find... 564whp from the Dynojet becoming 630hp is a 66hp (57tq) loss at 6000rpm. That is very fitting of this type of setup. Somethings you also should consider... The % suggestions state that: FF and RR lose 8-10% Mr and fr lose 10-15% Awd loses about 15-18% 4wd loses about 18-25%. All manuals. Autos lose an addition 5% in the guessing game. So in this case, an auto fr car should lose 20%. Even using the craptastic numbers they presented of 564whp and 675hp, we see 16% loss, which doesn’t stand up to the % game. Look, let me explain it to you like this, does an alternator, water pump, oil pump, and so on eat up gradually more tq just because the engine gets a pair of headers and a supercharger bolted on? Assume rpm doesn’t change, you might be spinning the oil pump a little harder, or the alternator a little harder to supply electricity for the fuel pump, but you don’t just assume you have an extra 25% more parasitic drag on the serpentine assembly because you add 25% more hp. If you take a 20lbs drive shaft, and hook it up to a thrust dyno, then measure the force needed to spin it to 6,000rpm, its resistance to spin won’t read any differently if you then slowly accelerate it to 6000rpm to represent 300tq, or very quickly accelerate it to 6000rpm to represent 900tq. Torque is being produced by the engine, and reaches the wheels after driving the drivetrain. The drivetrain is made out of metal and carbon fiber and alloys. None of those materials are spunge like globs of gum or honey that sap away torque. [/QUOTE]
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It's Official! 2020 GT500 Makes 760HP
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