500 HP - did I lie?

[turbojimmy]

So I was cruising along in traffic this morning and a guy motioned for me to roll down the window. I did and he said 'beautiful car - how much HP?'. I said 'around 500'. I'd never really thought about it before nor ever had it on a dyno - I just blurted it out. I've run the times in my sig, I figure it must weigh at least 3700 lbs. with me in it. That's probably 5xx at the crank and 4xx at the wheels, no?

The guy wrinkled up his face and said "I don't think so." I told him I had done quite a bit of work to it. He said he remembered when they first came out and they weren't THAT fast. I thanked him for the complement and put the window back up.

So is 500 HP that outrageous of a claim for a mid/low 11-sec GN trapping in the mid-high 11x MPH range? Maybe I'll get it on a dyno one of these days.

Just curious.

Jim

 

[JDSfastGN]

im curious as to the answer as well.... never had mine on a dyno, but i would hope it would dyno somewhere around 440hp/520 trq.... but its seems GNs dyno pretty low.

 

[67turboCamaro]

Try this out- http://www.speedworldmotorplex.com/calc.htm

 

[suicide six]

11sec car with 3700 lbs w/driver equals @549hp at wheels and 714 at flywheel.

 

[suicide six]

Same as above with 11.9 sec car equals 434 wheel 564 fly wheel hp

 

[JDSfastGN]

Try this out- http://www.speedworldmotorplex.com/calc.htm

Seems a bit on the optimistic side (472 rwhp) going by mph. I've used this one before and it seems a bit more realisitic to me, but who knows http://www.modulardepot.com/hpc.php

 

[67turboCamaro]

Seems a bit on the optimistic side (472 rwhp) going by mph. I've used this one before and it seems a bit more realisitic to me, but who knows http://www.modulardepot.com/hpc.php

Yea, I agree that one seems more believable.

 

[suicide six]

Agreed yet I think Turbojimmy is in the ballpark if his numbers are true.

 

[turbojimmy]

Agreed yet I think Turbojimmy is in the ballpark if his numbers are true.

Yep. That one puts me at around 500 at the crank; 400 at the wheels which makes sense.

Jim

 

[turbo2nr]

Take a step back and think about that. Plenty of 500-600HP Buicks running on mostly stock parts. What else can you buy with that much fun and style. Good gas milage as well. Holds it's value. Hmmm. I think I'll buy another.

 

[ijames]

The average TR that runs 117 mph will run an 11.59 so your et is very good for your mph. Mph is a better measure of hp (et tells you about traction), so using 11.59 and 3700 lbs some straightforward physics says you were making 468 average rear wheel hp. Inflating that by the typical 15-20% "hp loss" in a 200-4R gets you 550-585 average flywheel hp.

 

[vader87]

Mine dynoed at 503 fwhp and ran a 11.8 @ 115 MPH. So you are right on track. Probably under estimated your car!

 

[DragulaGN]

Mine dynoed at 503 fwhp and ran a 11.8 @ 115 MPH. So you are right on track. Probably under estimated your car!

Whne did they make a FWD GN?

 

[GNVYUS 1]

Nope you didn't lie, you actually gave him the lower power figure.

I always go off of the torque numbers, as if you notice those 450 rwHP GN's are cranking out about 525 rwTQ.

Next time tell you have have 600lbs of torque and then light'em up around 35mph to prove it!!

 

[turbojimmy]

Whne did they make a FWD GN?

Before foriegn cars stole the designation to mean "front wheel HP", FWHP meant 'flywheel HP'. But I thought a dyno measured wheel HP so I'm confused.

The run in my sig was actually 11.363 @ 117.47, so we can call it 11.4 (though I like to call it 11.3). It is a lot of ET for the MPH, but the car was hooking very well that night. Low 1.6 and high 1.5 60' times.

Thanks for the replies!

Jim

 

[vader87]

Well you take the the rwhp or crank horsepower and add 20%. Where do you get 20%, that is just the standard percentage that is used across the industry for drivetrain loss. So my car dynoed at 402 RWHP. Now add 20% and you come up with 503 fwhp OR crank horsepower.

The front wheel drive comment...come on, we all know that there are no front wheel drive Grand Nationals, and I really could care less about "front wheel drive horsepower".

 

[turbojimmy]

The front wheel drive comment...come on, we all know that there are no front wheel drive Grand Nationals, and I really could care less about "front wheel drive horsepower".

I just meant that I wasn't sure whether you meant flywheel HP or wheel HP. Not knowing a lot about dynos, I'm not sure if there are ones that report one or the other or both.

Jim

 

[Pablo]

I hate getting that question but when I do feel like answering it I give the same answer "around 500" and if they give a face like they dont believe it I tell them that hp numbers are meaningless anyway. I follow that up with my track times and tell them thats enough to blow away most anything i run across on the street.

Last conversation I had with someone brought up supras and I told him how they were a perfect example, alot of them dyno high but get smoked at the track

 

[8UWITH6]

My time below on the GN put down 406hp and 529tq in full tilt boogie mode. However, it was 115 degrees in the dyno room and had a little tiny fan on the front of it. Ill bet if it was 50 or 60 degrees, Id get my 500rwhp. Or if I install meth

 

[DCVING 6]

Should have told him you'd give him 5 spots and the bust.