where does horsepower and torque cross?

bigwhitecobra · 07-12-2003, 03:40 PM

I need a response asap. Isn't it at 5250rpm's? If I am wrong tell me so, if not can you point me to an article that points this out so that I can call someone on this? anyway, thanks in advance. Later.

Shaggy · 07-12-2003, 04:17 PM

It is 5250 except for a very few oddballs....LS1's being one of the oddballs. I am not sure why the oddballs don't and from an engineering standpoint they all should cross at 5250. So if anyone has some insight as to why some don't feel free to chime in. My best guess is that playing with the intake runner length to use the resonance waves to you advantage is the only thing i can really guess.

PS every ls1 i have seen chassis dynoed crosses aroun 5600.

Hethj7 · 07-13-2003, 08:45 PM

HP = Torque * RPM /5250

The 5250 is a conversion factor, and simple math shows you the two should be equal when RPM equals 5250.

PKRWUD · 07-13-2003, 09:40 PM

Actually, it's 5252rpm.

hp = rpm x torque /5252

Take care,
~Chris

PKRWUD · 07-13-2003, 09:47 PM

here's one from an '01 Corvette...

PKRWUD · 07-13-2003, 09:56 PM

Quote:

Originally posted by Shaggy
It is 5250 except for a very few oddballs....LS1's being one of the oddballs. I am not sure why the oddballs don't and from an engineering standpoint they all should cross at 5250. So if anyone has some insight as to why some don't feel free to chime in. My best guess is that playing with the intake runner length to use the resonance waves to you advantage is the only thing i can really guess.

PS every ls1 i have seen chassis dynoed crosses aroun 5600.

I've heard of "the new math", but I still don't think that's possible.

Check these

Take care,
~Chris

BilLster · 07-13-2003, 10:05 PM

I've alway's been told HP is calculated the way PKRWUD Showed HP= Rpm x TQ / 5252 but have seen some new math also .

for bike's there is a new dyno similiar to a mustang dyno for cars and all it really does is fluctuate the 5252 to a higher number to lower the static HP figure. no dyno I know of messures Horsepower as far as my little world goes they all messure TQ and calculate HP.

Hethj7 · 07-13-2003, 11:21 PM

Quote:

Originally posted by PKRWUD
Actually, it's 5252rpm.

hp = rpm x torque /5252

Take care,
~Chris

Your answers are always a little better than mine

Rev · 07-15-2003, 07:35 PM

The HP and Torque curves will ALWAYS cross at 5252 rpm's if the the HP scale and the TQ scale are the same. I've had some dyno sheets where the HP scale and the TQ scale were different for some screwball reason?. This kind of graphical BS throws everthing askew (DynoJet, are you listening?????).

If the scale on the graph for HP and TQ are the same, then the graphs will cross at 5252 rpm, just as everyone has said.

Rev

bigwhitecobra · 07-16-2003, 03:36 PM

Thanks guys. I knew that it crossed at that RPM, I just couldn't explain why. Thanks again. Later.

07-12-2003, 03:40 PM	#1
bigwhitecobra Huh? Whatcha said? Join Date: Oct 2000 Location: Fayetteville, NC Posts: 1,073	where does horsepower and torque cross? I need a response asap. Isn't it at 5250rpm's? If I am wrong tell me so, if not can you point me to an article that points this out so that I can call someone on this? anyway, thanks in advance. Later. __________________ 2003 GT White---STOLEN May you burn in hell whoever took it. Dumbazz didn't even get the good engine that was in the garage.

07-12-2003, 04:17 PM	#2
Shaggy Registered Member Join Date: Feb 1999 Location: Houston,TX Posts: 466	It is 5250 except for a very few oddballs....LS1's being one of the oddballs. I am not sure why the oddballs don't and from an engineering standpoint they all should cross at 5250. So if anyone has some insight as to why some don't feel free to chime in. My best guess is that playing with the intake runner length to use the resonance waves to you advantage is the only thing i can really guess. PS every ls1 i have seen chassis dynoed crosses aroun 5600. __________________ A good plan, violently executed now, is better than a perfect plan next week. George S. Patton, General (1885-1945)

07-13-2003, 08:45 PM	#3
Hethj7 Mizzou Tigers Join Date: Apr 1999 Location: weston, MO United States Posts: 1,455	HP = Torque * RPM /5250 The 5250 is a conversion factor, and simple math shows you the two should be equal when RPM equals 5250. __________________ 2006 Mustang GT 1990 LX GT-40 motor 262 horsepower, 307ft-lbs (sold but forever loved) 1998 Contour SVT Rice Haters Club Member #244

07-13-2003, 09:40 PM	#4
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Actually, it's 5252rpm. hp = rpm x torque /5252 Take care, ~Chris __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-13-2003, 09:47 PM	#5
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	here's one from an '01 Corvette... __________________ Webmaster: Rice Haters Club Jim Porter Racing Peckerwoods Pit Stop Support Your Local RED & WHITE!

07-13-2003, 10:05 PM	#7
BilLster Registered Member Join Date: Oct 2000 Location: Ontario canada Posts: 446	I've alway's been told HP is calculated the way PKRWUD Showed HP= Rpm x TQ / 5252 but have seen some new math also . for bike's there is a new dyno similiar to a mustang dyno for cars and all it really does is fluctuate the 5252 to a higher number to lower the static HP figure. no dyno I know of messures Horsepower as far as my little world goes they all messure TQ and calculate HP. __________________ 89 with 331 t3'/t4 hybrids. upr Suspention worked out finnaly . 9.89 144 mph .

07-15-2003, 07:35 PM	#9
Rev Registered Member Join Date: Nov 1998 Location: Houston, Tx. Posts: 3,887	Scales? The HP and Torque curves will ALWAYS cross at 5252 rpm's if the the HP scale and the TQ scale are the same. I've had some dyno sheets where the HP scale and the TQ scale were different for some screwball reason?. This kind of graphical BS throws everthing askew (DynoJet, are you listening?????). If the scale on the graph for HP and TQ are the same, then the graphs will cross at 5252 rpm, just as everyone has said. Rev __________________ '66 Coupe, 306, 350-375 HP, C-4, 13.07 e.t., 104.8 mph, 1/4 mi. O.B.C. #2 '66 coupe

07-16-2003, 03:36 PM	#10
bigwhitecobra Huh? Whatcha said? Join Date: Oct 2000 Location: Fayetteville, NC Posts: 1,073	Thanks guys. I knew that it crossed at that RPM, I just couldn't explain why. Thanks again. Later. __________________ 2003 GT White---STOLEN May you burn in hell whoever took it. Dumbazz didn't even get the good engine that was in the garage.

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