HP Rating NOT Really Overrated As Some Think

ZKindaGuy · 11-07-2009, 10:46 AM

Just for the heck of it I decided to run some 370Z 1/4-mile track numbers I found on the Internet to see what the HP numbers calculate to using a HP calculator. Here is what I started with:

Best 1/4-mile time I found:

13.1 @ 108.9 MPH

370Z spec:

Bone stock
MT-6
Spec weight
car is 3278 lbs empty
car is 3285 lbs assuming 1 gallon of fuel.

Best 1/4 mile time found: 13.1 seconds

Assuming driver #1 weighs 180 pounds (the weight of an average man) the total weight at race time is: 3465 lbs

Assuming driver #2 weighs 200 pounds (an above average weight) the total weight at race time is: 3485 lbs

Calculation results:

HP with driver #1: 326.94 HP at the flywheel

HP with driver #2: 328.83 HP at the flywheel

So my conclusion is that given the stated Nissan spec rating of 332 BHP the 1/4-mile track numbers tend to support such an OEM rating by +/- 4 HP.

MightyBobo · 11-07-2009, 11:50 AM

There were people who thought the HP was overrated?

m4a1mustang · 11-07-2009, 11:57 AM

Yeah, really.

MightyBobo · 11-07-2009, 12:18 PM

Quote:

Originally Posted by m4a1mustang

Yeah, really.

You'd think the multitudes of similar dyno graphs would have proven that, and trap speeds in the 1/4th...

semtex · 11-07-2009, 12:44 PM

Still good info nonetheless.

Lug · 11-07-2009, 12:56 PM

I've carefully studied the supplied data and have come to one conclusion. I'm fat.

F430Spider · 11-07-2009, 01:05 PM

Quote:

Originally Posted by Lug

I've carefully studied the supplied data and have come to one conclusion. I'm fat.

Rofl

Modshack · 11-07-2009, 02:55 PM

Here's a link to a few on-line calculators....

Acceleration Calculators

vash_241987 · 11-07-2009, 03:06 PM

Quote:

Originally Posted by ZKindaGuy

Just for the heck of it I decided to run some 370Z 1/4-mile track numbers I found on the Internet to see what the HP numbers calculate to using a HP calculator. Here is what I started with:

Best 1/4-mile time I found:

13.1 @ 108.9 MPH

370Z spec:

Bone stock
MT-6
Spec weight
car is 3278 lbs empty
car is 3285 lbs assuming 1 gallon of fuel.

Best 1/4 mile time found: 13.1 seconds

Assuming driver #1 weighs 180 pounds (the weight of an average man) the total weight at race time is: 3465 lbs

Assuming driver #2 weighs 200 pounds (an above average weight) the total weight at race time is: 3485 lbs

Calculation results:

HP with driver #1: 326.94 HP at the flywheel

HP with driver #2: 328.83 HP at the flywheel

So my conclusion is that given the stated Nissan spec rating of 332 BHP the 1/4-mile track numbers tend to support such an OEM rating by +/- 4 HP.

ssoooo the fatter you are the more HP your car will have

at my weight a 370z would have 5000000hp

........but on a serious note what is with the extra weight and the extra 2hp?

Supergoji · 11-07-2009, 03:18 PM

Quote:

Originally Posted by vash_241987

ssoooo the fatter you are the more HP your car will have

at my weight a 370z would have 5000000hp

........but on a serious note what is with the extra weight and the extra 2hp?

if you make the car heavier and change only the weight while all other stats remain the same, the car has more hp. because it's moving more weight in the same amount of time as the lighter car.

gleonard · 11-07-2009, 03:25 PM

it means the extra weight would need 2 more hp to go that fast in the 1/4 mile

ZKindaGuy · 11-07-2009, 03:25 PM

Quote:

Originally Posted by vash_241987

ssoooo the fatter you are the more HP your car will have

at my weight a 370z would have 5000000hp

........but on a serious note what is with the extra weight and the extra 2hp?

HP is actually a function of weight. I know its confusing but think about it this way. The heavier the total load that is moving the greater HP is required to move the load in that given time over that given distance. It isn't that the engine is manufacturing more HP....its that the calculation formula figures the vehicle's HP to be "x" given the stated weight, time, speed and distance traveled. That is why the 1/4 mile is the truest indicator of what a car's HP is on any given run.

Modshack · 11-07-2009, 03:38 PM

Quote:

Originally Posted by ZKindaGuy

The heavier the total load that is moving the more HP is required to move the load

Here's a great (funny) article on the whole concept of weight Vs. speed....

SCC Technical Assistance Program

ZKindaGuy · 11-07-2009, 03:40 PM

Quote:

Originally Posted by MightyBobo

There were people who thought the HP was overrated?

Yes...actually the Camaro boards are of that opinion (of course). They all think their crap doesn't stink. I saw a new Camaro parked at Summit Racing in Tallmadge, Ohio yesterday. To be honest the car looked like a POS. It was yellow which didn't help..but it looks really cheap...and it looks like an absolute bloated BOAT in its profile...the tires look like mega-balloons. I walked away with the impression that this was the typical "GM doesn't know how to design any car except a Vette" look.

And believe it or not there are some Z folks (mostly 350Z folks) that think the 370Z HP is overrated. And there are a few car-magazines that I have seen it mentioned that whomever was doing the review felt that the 370Z may be overrated in HP.

Needless to say what I showed in my example using actual trap data and the most conservative of assumptions the OEM specified HP for the 370Z has to be very accurate.

Mercennarius · 11-07-2009, 04:16 PM

Quote:

Originally Posted by ZKindaGuy

Yes...actually the Camaro boards are of that opinion (of course). They all think their crap doesn't stink. I saw a new Camaro parked at Summit Racing in Tallmadge, Ohio yesterday. To be honest the car looked like a POS. It was yellow which didn't help..but it looks really cheap...and it looks like an absolute bloated BOAT in its profile...the tires look like mega-balloons. I walked away with the impression that this was the typical "GM doesn't know how to design any car except a Vette" look.

And believe it or not there are some Z folks (mostly 350Z folks) that think the 370Z HP is overrated. And there are a few car-magazines that I have seen it mentioned that whomever was doing the review felt that the 370Z may be overrated in HP.

Needless to say what I showed in my example using actual trap data and the most conservative of assumptions the OEM specified HP for the 370Z has to be very accurate.

Given the dyno #s we've seen so far and the trap speeds that have been published it appears the 370Z is underrated more then over rated...though to be honest I think its rated exactly right.

11-07-2009, 10:46 AM	#1 (permalink)
ZKindaGuy Track Member Join Date: May 2009 Location: Ohio Posts: 699 Drives: 370Z-AT7 Tour+Sport Rep Power: 375	HP Rating NOT Really Overrated As Some Think Just for the heck of it I decided to run some 370Z 1/4-mile track numbers I found on the Internet to see what the HP numbers calculate to using a HP calculator. Here is what I started with: Best 1/4-mile time I found: 13.1 @ 108.9 MPH 370Z spec: Bone stock MT-6 Spec weight car is 3278 lbs empty car is 3285 lbs assuming 1 gallon of fuel. Best 1/4 mile time found: 13.1 seconds Assuming driver #1 weighs 180 pounds (the weight of an average man) the total weight at race time is: 3465 lbs Assuming driver #2 weighs 200 pounds (an above average weight) the total weight at race time is: 3485 lbs Calculation results: HP with driver #1: 326.94 HP at the flywheel HP with driver #2: 328.83 HP at the flywheel So my conclusion is that given the stated Nissan spec rating of 332 BHP the 1/4-mile track numbers tend to support such an OEM rating by +/- 4 HP. Last edited by ZKindaGuy; 11-07-2009 at 10:49 AM.

11-07-2009, 11:50 AM	#2 (permalink)
MightyBobo A True Z Fanatic Join Date: Feb 2009 Location: Las Vegas, NV Posts: 8,465 Drives: No cars; only bikes Rep Power: 52	There were people who thought the HP was overrated? __________________ I don't own a car anymore.

11-07-2009, 11:57 AM	#3 (permalink)
m4a1mustang A True Z Fanatic Join Date: Feb 2009 Location: Northern VA Posts: 55,385 Drives: on two wheels Rep Power: 6962	Yeah, really. __________________ - Steve Zs & Coffee - Saturdays at 10AM in Fairfax, VA and Columbia, MD (Click the banner!) LIKE us on Facebook!

11-07-2009, 12:44 PM	#5 (permalink)
semtex A True Z Fanatic Join Date: Jan 2009 Location: Behind enemy lines Age: 54 Posts: 5,995 Drives: People to drink Rep Power: 32	Still good info nonetheless. __________________ "There are no small accidents on this circuit." -- Ayrton Senna 316.8whp & 248 ft/lbs (Dyno Dynamics) \| 319whp & 256 ft/lbs (DynoJet) (04/23/10) Stillen G3 CAI, CBE, Pulley / F.I. LTH / GTSpec Ladder Brace / Setrab Oil Cooler / UpRev-tuned by Forged Perf.

11-07-2009, 12:56 PM	#6 (permalink)
Lug A True Z Fanatic Join Date: Dec 2008 Location: Texas Posts: 1,926 Drives: 2006 350Z Rep Power: 19	I've carefully studied the supplied data and have come to one conclusion. I'm fat. __________________ keep Chubbs in your pocket - Chubbs

11-07-2009, 02:55 PM	#8 (permalink)
Modshack A True Z Fanatic Join Date: Mar 2009 Location: Greenville NC Posts: 2,883 Drives: 370Z Sport Rep Power: 976	Here's a link to a few on-line calculators.... Acceleration Calculators __________________ Steal my car! (SOLD)...Now Porsche Cayman S Oil Cooler DIY: Here!

11-07-2009, 03:25 PM	#11 (permalink)
gleonard Base Member Join Date: Jul 2009 Location: Los Angeles Posts: 196 Drives: 370z Touring/Spt 6sp Rep Power: 16	it means the extra weight would need 2 more hp to go that fast in the 1/4 mile