So tired of hearing HP/L (Page 1/2)
Xyster MAY 10, 10:15 AM
I am so tired of hearing about HP/L and not BMEP.

BMEP is (for those of you wondering) ft-lbs/cid*150.8. This number is based what the engine does and the only way to improve it is to build a better engine.

Engines produce torque. Hp is a function of torque at a given rpm. So, if you can't produce torque, spin the crap out of your engine and use hp/L to make it sound like you made a good engine. Heck, Honda does it and all the magazines love their high NVH/short life span engines.

So, now for those thinking, it takes a "better engine" to turn higher rpms, remember, GM, Ford and Mopar engines are cammed for street use, not ads showing a tach at 8k rpm. [/rant]
Gokart Mozart MAY 15, 08:48 PM
How about HP/LB?
Xyster MAY 24, 11:23 AM
I actually don't mind HP/Lb when discussing accelerating to street speeds.

Eg. a 2012 civic si 2 door with its 14.3 lb per hp has a 0-60 of 6.4 source
a 1997 grand prix 4 door with its 14.2 lb per hp has a 0-60 of 6.5 source

However, when you leave the realm of street speeds, HP-lb becomes less and less significant.

Eg. my motorcycle has a similar HP-lb as a Veyron. As a result we have similar 0-60 times. Unfortunately (or maybe fortunately for my life) after 100 the Bug just leaves me in the dust.

So, the short answer is HP-LB is fine for 0-60 times but that is about it.
Time Traveller JUL 01, 10:49 PM
Wouldn't BMEP scores tend to favor disproportionately torquey diesel engines?

I guess I'm in the HP/lb (sometimes shown as HP/ton) camp... It's the most basic physics of the thing. Your engine exerts power to move the car... How fast it can move the car depends on how much power is available, and the mass you're trying to move.

Everything else (top speeds, etc) comes down to transmission gearing, governing, aerodynamics, etc.

This is funny because one of my coworkers was just talking about how his Honda S2000 was the highest HP/L for a naturally aspirated car at the time he owned it...
weaselbeak JUL 03, 12:50 AM
Ask your Honda buddy how much torque he makes at 4K

[This message has been edited by weaselbeak (edited 07-03-2013).]

Xyster JUL 03, 02:44 PM
Q. How ridiculously low is the S2k geared to compensate for the lack of torque?
A. Very. 3.1 in first and 4.10 in the diff.
Corvette numbers for example are around 2.3 in first and 3.42 in the diff.
Fformula88 JUL 03, 03:22 PM
Meh, neither is all that important to me. If it is a respectably powerful engine, in a good chassis, and they work together in harmony to offer a great performance driving experience then I am not all that concerned with the actual raw numbers.

The most efficient and powerful engine mounted in a pile of crap is still just a fast pile of crap.
Xyster JUL 03, 03:40 PM

quote
Originally posted by Fformula88:

1 Meh, neither is all that important to me. If it is a respectably powerful engine, in a good chassis, and they work together in harmony to offer a great performance driving experience then I am not all that concerned with the actual raw numbers.

2 The most efficient and powerful engine mounted in a pile of crap is still just a fast pile of crap.



1 Too true. Many people (especially me) get too wrapped around the axles discussing numbers.

2 Makes me think of Farmtruck on Street Outlaws.
rogergarrison JUL 05, 10:38 AM
I like Farmtruck...he kicks butt.

I dont give a crap what useless numbers a computer throws out. I want to see it on the street.
Xyster JUL 08, 11:16 AM
As further proof that hp/l is an advertising gimmick, who won at Le Mans yet again?