100 horsepower per liter naturally aspirated
06-07-2007, 06:05 PM
#101
TECH Senior Member
Originally Posted by FieroZ34
How about I find you one that makes 400hp, but 250tq? With the right transmission, it will drive just the same, and accelerate just as hard.
06-07-2007, 06:07 PM
#102
TECH Senior Member
Originally Posted by FieroZ34
However, the brilliance of the M5 is that it can drive and perform just like motors that have much better low end torque numbers.
06-07-2007, 08:31 PM
#103
TECH Enthusiast
Join Date: Feb 2007
Location: Seattle area
Posts: 686
Likes: 0
Received 0 Likes
on
0 Posts
As Mercedes has proven with the E63 BMW would have been better off taking the S62 V8 to the next level rather than tech for techs sake. IMO it could not have been that difficult to acheive at least the 470 hp and 419 torque Dinan was able to squeeze out of the engine.
06-07-2007, 10:17 PM
#104
TECH Enthusiast
iTrader: (4)
Join Date: Aug 2003
Location: Phoenix AZ
Posts: 633
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by FieroZ34
I
But from a minimalistic point of view, that simply means the LS1 and LS2 are underperforming and poorly engineered.
But from a minimalistic point of view, that simply means the LS1 and LS2 are underperforming and poorly engineered.
Lighter, Smaller, Less **** to break.
GM has made alot of improvements since the first high compression pushrod v8(oldsmobile rocket v8) was made in 1949.
DOHC has had since the 1912 fiat's to perfect its technology.
L92's have variable valve timing now.
Give the pushrods some time.
Last edited by Gen3Benz; 06-07-2007 at 10:33 PM.
06-07-2007, 11:35 PM
#105
Originally Posted by louie83
Take two identical cars. One with a 500 HP / 300 lb ft engine and one with a 500 HP / 500 lb ft engine. The second one wins because it has more torque and therefore, MORE HORSEPOWER TOO. Wait, what? They both have 500 HP. The car obviously doesn't make 500 HP the entire time the pedal is mashed, the higher torque of the second engine equates to higher average horsepower throughout the RPM range.
Originally Posted by FieroZ34
As for your example, there's no way to know which one will win. Assume the M5 weighs as little as the Vette, and has the same aerodynamics. Now, there's no way to tell which one will win. Because as I said before, the torque...OH GOD SORRY, the time the engine spends out of its tuned rev range, doesn't matter, especially when you have a transmission that can keep you in your rev range all the time.
You're not in that rev range all of the time, because it's not a rev 'range.' A 500 HP engine is PEAK. That's how we measure them. Unless we are using variable transmissions, a 500 HP / 300 lb ft engine and a 500 HP / 500 lb won't be in the same engine rev 'range' all of the time. We're not using variable trannys, they're six speeds.. Therefore, no matter how good your transmission is, until peak power, the engine with more torque WILL make more power. That's the way the formula works.
Another thing to consider is that if an engine is geared to accelerate quickly due to lack of torque, it will turn FAR more RPMs at higher engine speeds, unless given more gears in the transmission. So, since BMW and GM both use 6-speeds, and both accelerate the same (for the sake of argumet of TQ vs GEAR), GM through torque and BMW through gears, GM will get better highway (and city, but not by as much) mileage.
06-08-2007, 08:08 AM
#107
Originally Posted by IFRYRCE
No.
You're not in that rev range all of the time, because it's not a rev 'range.' A 500 HP engine is PEAK. That's how we measure them. Unless we are using variable transmissions, a 500 HP / 300 lb ft engine and a 500 HP / 500 lb won't be in the same engine rev 'range' all of the time. We're not using variable trannys, they're six speeds.. Therefore, no matter how good your transmission is, until peak power, the engine with more torque WILL make more power. That's the way the formula works.
Another thing to consider is that if an engine is geared to accelerate quickly due to lack of torque, it will turn FAR more RPMs at higher engine speeds, unless given more gears in the transmission. So, since BMW and GM both use 6-speeds, and both accelerate the same (for the sake of argumet of TQ vs GEAR), GM through torque and BMW through gears, GM will get better highway (and city, but not by as much) mileage.
You're not in that rev range all of the time, because it's not a rev 'range.' A 500 HP engine is PEAK. That's how we measure them. Unless we are using variable transmissions, a 500 HP / 300 lb ft engine and a 500 HP / 500 lb won't be in the same engine rev 'range' all of the time. We're not using variable trannys, they're six speeds.. Therefore, no matter how good your transmission is, until peak power, the engine with more torque WILL make more power. That's the way the formula works.
Another thing to consider is that if an engine is geared to accelerate quickly due to lack of torque, it will turn FAR more RPMs at higher engine speeds, unless given more gears in the transmission. So, since BMW and GM both use 6-speeds, and both accelerate the same (for the sake of argumet of TQ vs GEAR), GM through torque and BMW through gears, GM will get better highway (and city, but not by as much) mileage.
06-08-2007, 08:16 AM
#108
Originally Posted by JD_AMG
There's nothing "brilliant" about compensating with higher gear ratios to make up for less engine torque.
You put equal gearing in a ls7 and it will rip the head off of the bmw engine(like it does already)
Tech for the sake of tech is for the people with more money than sense.
Look at what it did to Ford
Don't get me wrong, I love BMW's. I would love to own one, probably will one day. But by no means do I think that everything they do is the gospel. They are built with a different purpose and intent than what most american cars are. Their customers value being coddled more than anything. If the engien makes the right sounds(read very little) and vibrations(same) and has the BMW symbol on it, then they are happy as a pig in ****.
Most die-hard Bimmer guys would never consider owning a f-body. It would be to "crude" and "archaic" for them. For me I love the fact that my car is rough, loud, tempermental and smells like gas.
06-10-2007, 11:49 AM
#111
I'm not sure if this has been brought up, discussed, posted yet, but the most recent 600 cc sportbikes are in excess of 200 hp/L. That's impressive whether you think hp/L is valid or not. Torque peaks are around 11,000 rpm and hp is around 13,000, with the Yamaha peaking at 14,000 rpm. And these things idle very smooth and pull decent at low rpm without variable cam timing. I can take off in 2nd gear on my ZX-10R (185 hp/L) and hold that gear all the way to 115 mph! Note from the dyno graph that 75% of peak torque is available from 6,000 rpm up to 15,000 rpm.
http://www.sportrider.com/bikes/046_..._dyno_testing/
Mike
http://www.sportrider.com/bikes/046_..._dyno_testing/
Mike
06-10-2007, 12:01 PM
#112
TECH Fanatic
iTrader: (3)
Join Date: Jun 2004
Location: Dayton, OH
Posts: 1,844
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by engineermike
I'm not sure if this has been brought up, discussed, posted yet, but the most recent 600 cc sportbikes are in excess of 200 hp/L. That's impressive whether you think hp/L is valid or not. Torque peaks are around 11,000 rpm and hp is around 13,000, with the Yamaha peaking at 14,000 rpm. And these things idle very smooth and pull decent at low rpm without variable cam timing. I can take off in 2nd gear on my ZX-10R (185 hp/L) and hold that gear all the way to 115 mph! Note from the dyno graph that 75% of peak torque is available from 6,000 rpm up to 15,000 rpm.
http://www.sportrider.com/bikes/046_..._dyno_testing/
Mike
http://www.sportrider.com/bikes/046_..._dyno_testing/
Mike
I would actually prefer DOHC myself if I were working with a really short stroke. The problem comes from ignorant kids who think that HP/L tells you the whole story about the engine. When you mention HP/weight of the engine, they just stare at you with a blank look on their face.
06-10-2007, 01:04 PM
#113
TECH Enthusiast
Join Date: Feb 2007
Location: Seattle area
Posts: 686
Likes: 0
Received 0 Likes
on
0 Posts
I agree bike engines are amazing...but we are talking about cars here...and moving 3,000-4,000 lb car requires not just top end power but power under the curve.
06-10-2007, 02:10 PM
#114
Staging Lane
Join Date: Mar 2007
Posts: 60
Likes: 0
Received 0 Likes
on
0 Posts
problem with bike engines is they are low on torque. even 500+hp turbo hayabusas will likely have like 265 ftlbs torque. as far as power to weight bikes are pretty damn strong, bike engines are very light and compact with the transmission being part of the engine. ididnt read all 6 pages of this post, but there are a few places developing and using a V8 hayabusa engine putting out about 380hp, 10,000 rpm, 2.6 liter.
06-10-2007, 02:19 PM
#115
Staging Lane
Join Date: Mar 2007
Posts: 60
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by GMC_DUDE
Another way to look at it. The Co. I work for builds 18-wheeler trucks. One of the engines we offer is a Cummins ISX which can be had in up to 565 HP. Now many passenger car owners have engines which put out that much HP or more. But that Cummins engine in one of our trucks will pull a fully loaded semi trailer up a mountain grade without breaking a sweat. I would like to see any passenger car with the same HP gas engine do likewise. Bottom line: HP (or HP/Liter) does not tell the whole story. Over and out.
you cannot compare a turbo diesel to ANY gasoline engine. that 565 HP turbo diesel is putting down in the neighborhood of 1,200 ftlbs torque, probably much more... a normal cummins dodge ram turbo diesel modified to put down 500+hp will be between 1000-1200ft lbs torque. 18wheeler engines are MUCH larger and obviously designed to pull HUGE loads full time. probably redlines at 3,000rpm.
COMPLETELY ENTIRELY different ballpark. if you try comparing gasoline engines to gasoline engines or engines that generally produce near the same torque levels as HP levels then you are atleast in the ballpark.
06-10-2007, 03:29 PM
#116
TECH Enthusiast
Join Date: Feb 2007
Location: Seattle area
Posts: 686
Likes: 0
Received 0 Likes
on
0 Posts
After driving a relatively peaky car for a couple years, I no longer care so much about hp/liter....
Its just like working out for you guys that do, just because one guy has a lower body fat percentage than you do doesn't mean he can kick your ***!
Its just like working out for you guys that do, just because one guy has a lower body fat percentage than you do doesn't mean he can kick your ***!
06-10-2007, 07:34 PM
#117
Originally Posted by squirts1
problem with bike engines is they are low on torque.
:edit: I did some looking and the 350 LS1's are coming in at 390 - 430 ft-lb at the rear wheels, depending on mod's. Guess those sport bikes aren't so low on torque after all. . . Also, my ZX-10R is geared very tall in first - so tall that it will do 105 mph in 1st gear! With that tall gearing, it will still do roll-on wheelies anywhere between 50 and 90 mph, so it has plenty enough torque.
Mike
Last edited by engineermike; 06-10-2007 at 07:54 PM.
06-12-2007, 06:09 AM
#118
Originally Posted by GMC_DUDE
...and a high HP bike engine would have a hard time moving an F-body. I said it once, but it's worth repeating: Peak HP does NOT tell the whole story.
You can gear to improve torque, but you're stuck with whatever hp the engine makes.
For example. Let's take a your typical turbocharged Hayabusa 1300 motor. A hot one will make in the neighborhood of 350 rwhp and 180 ft-lb of torque. Now, an LS1 with a 4L60E, 3.42 gear, and 26" tires will hit 6000 rpm at about 44 mph. Lets install a turbo Hayabusa motor in an F-body and gear it to max out first gear at the same speed. That would require a 6.80 or so rear gear to get 12,000 rpm at 44 mph. Now, look the torque figure. The 180 ft-lb with a 6.80 rear gear has the same pulling power as 360 ft-lb with a 3.42 gear. Hmmm, pretty close to an LS1 in the torque department now, eh?
Mike
06-12-2007, 09:26 AM
#119
Launching!
Join Date: Jul 2004
Posts: 291
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by engineermike
See, I disagree. People will argue this til they're blue in the face, but. . .
You can gear to improve torque, but you're stuck with whatever hp the engine makes.
For example. Let's take a your typical turbocharged Hayabusa 1300 motor. A hot one will make in the neighborhood of 350 rwhp and 180 ft-lb of torque. Now, an LS1 with a 4L60E, 3.42 gear, and 26" tires will hit 6000 rpm at about 44 mph. Lets install a turbo Hayabusa motor in an F-body and gear it to max out first gear at the same speed. That would require a 6.80 or so rear gear to get 12,000 rpm at 44 mph. Now, look the torque figure. The 180 ft-lb with a 6.80 rear gear has the same pulling power as 360 ft-lb with a 3.42 gear. Hmmm, pretty close to an LS1 in the torque department now, eh?
Mike
You can gear to improve torque, but you're stuck with whatever hp the engine makes.
For example. Let's take a your typical turbocharged Hayabusa 1300 motor. A hot one will make in the neighborhood of 350 rwhp and 180 ft-lb of torque. Now, an LS1 with a 4L60E, 3.42 gear, and 26" tires will hit 6000 rpm at about 44 mph. Lets install a turbo Hayabusa motor in an F-body and gear it to max out first gear at the same speed. That would require a 6.80 or so rear gear to get 12,000 rpm at 44 mph. Now, look the torque figure. The 180 ft-lb with a 6.80 rear gear has the same pulling power as 360 ft-lb with a 3.42 gear. Hmmm, pretty close to an LS1 in the torque department now, eh?
Mike
Let's drag race these two setups and see how things work out.
I'm guessing the 1300 and ls1 will have the same gearbox, torque convertor size and stall?
That's allot to turn.
Last edited by B T; 06-12-2007 at 09:40 AM.
06-12-2007, 09:43 AM
#120
Originally Posted by engineermike
See, I disagree. People will argue this til they're blue in the face, but. . .
You can gear to improve torque, but you're stuck with whatever hp the engine makes.
For example. Let's take a your typical turbocharged Hayabusa 1300 motor. A hot one will make in the neighborhood of 350 rwhp and 180 ft-lb of torque. Now, an LS1 with a 4L60E, 3.42 gear, and 26" tires will hit 6000 rpm at about 44 mph. Lets install a turbo Hayabusa motor in an F-body and gear it to max out first gear at the same speed. That would require a 6.80 or so rear gear to get 12,000 rpm at 44 mph. Now, look the torque figure. The 180 ft-lb with a 6.80 rear gear has the same pulling power as 360 ft-lb with a 3.42 gear. Hmmm, pretty close to an LS1 in the torque department now, eh?
Mike
You can gear to improve torque, but you're stuck with whatever hp the engine makes.
For example. Let's take a your typical turbocharged Hayabusa 1300 motor. A hot one will make in the neighborhood of 350 rwhp and 180 ft-lb of torque. Now, an LS1 with a 4L60E, 3.42 gear, and 26" tires will hit 6000 rpm at about 44 mph. Lets install a turbo Hayabusa motor in an F-body and gear it to max out first gear at the same speed. That would require a 6.80 or so rear gear to get 12,000 rpm at 44 mph. Now, look the torque figure. The 180 ft-lb with a 6.80 rear gear has the same pulling power as 360 ft-lb with a 3.42 gear. Hmmm, pretty close to an LS1 in the torque department now, eh?
Mike
Honestly, high rpms and short gears do work (Look at F1) but the tradeoffs required are not worth it in any automotive application except (F1)