No Replacement for Displacement

[McAdam]

yes, most bikes do out accelerate any car on the road. And they dont need big block power to do it. Power to weight.

I have seen some Mustangs in my town that used to race bikes for cash. barely streetable 347 SBF with huuuuge lumpy cams and a lot of n2o. either that or turbos. but now that the 'Busa is out, its a whole 'nother ball game!

McAdam

[stutt944]

half on topic:

driving down I-85 South to pick up my girl at the airport, i was passed by some hardcore bikers. full gear, top-notch bikes, the works. it is my understanding that their outing for the night mainly features outrunning the 5-oh. is this common practice on the ATL interstates?

[MrFox]

yes, most bikes do out accelerate any car on the road. And they dont need big block power to do it. Power to weight.

Not big block power...But still plenty of power.15500 RPMs worth in an R6.

600cc.200hp/literThat's 120 ponies, in an engine I can *almost* lift with 1 hand.

That is the reason why displacement is due for replacement.

[tl1000sga]

Not big block power...But still plenty of power.15500 RPMs worth in an R6.

600cc.200hp/literThat's 120 ponies, in an engine I can *almost* lift with 1 hand.

That is the reason why displacement is due for replacement.

Most R6's are good for around 90 hp, the '03 R6 had about 105 hp. There isn't a production 600cc bike with 120 hp. superbike engines are highly modified from the factory, and I haven't seen any with less than 11 to 1 compression. And how many superbikes have you seen go past 40k miles? Only the babied ones make it past that, and not much further. My TLS has 20,000 miles, and that's consider high mileage for it.:freak

[tl1000sga]

half on topic:

driving down I-85 South to pick up my girl at the airport, i was passed by some hardcore bikers. full gear, top-notch bikes, the works. it is my understanding that their outing for the night mainly features outrunning the 5-oh. is this common practice on the ATL interstates?

Yes, there are a few bike "clubs" in Ga like this. Me and my boys like to show off on the highways. We're there for the stunts, but it usually ends up with us dippin' on the police.:freak

[D-UNIT]

Yes yes turbo hayabusa yum! 1300cc turbo motor good for 220 whp , a crazy 1/4 mile time and a top speed of 230+ mph!!!! Awesome right!?! well not quite. Now let's up the DISPLACEMENT!!!!

I've seen small block 350's on harleys. Probably can't handle for crap. I've never seen a big block on a bike. oh wait a minute I have!!!

Enter the Dodge Tomahawk.

http://www.caranddriver.com/ar...=5448

8000cc V-10 500 low tech , two vavle , pushrod horsepower. Good for an ungodly 1/4 mile and 400+ mph!!! You want to test it?? If you still want to get psycho you could always Twin turbo it. then the question is how fast do you want to DIE!!!!

btw it weighs in at 1500 pounds!!! Now that is a power to weight ratio!!!!

[D-UNIT]

And I'm not even going to talk about adding TECHNOLOGY to that ^^!!!

[tl1000sga]

You can get a 502 ci big block on those v8 bikes now. I saw one with a 8-71 blower sticking up thru the tank. well, now that i think about it, the tank basically went around the blower. They claim a possible top speed of 400+ MPH an the tomahawk, but that is an estimated speed. I don't believe a bike without a shell over it has done anywhere near that speed. Bikes are an aerodinamics nightmare.

[s13sr20chris]

bikes are cool i think. i prefer cars. bikes will always win on the street, but lets take the top racing class of each. f1 vs (insert whatever the best race bike series is). i cant imagine a bike whupping up on an f1 car.

boss hogs: i think freud would love to comment here. mr. freud

hi im sigmund freud. anyone who needs big displacement on a motorcycle has a small pen15. can i have some crack now?

no mr. freud. see you later. i just got back online after the stupid hurricane that hit virginia so let me address something from way back. oops, i need to quote someone now...

edit:ever seen a hayabusa at an autocross?another edit:hp is what really matters in a race=facthp per liter is a good measure of technology=sortai resisted the impulse to put =retarded because there is some tech involved in high hp output, but it is much harder to get high torque per liter(atmo). s2000 is great as far as it goes, but look at this 240hp/2000cc=.12 thats great.197hp/1600cc=.123125 thats better.its close i know but the sr16ven1 has higher specific hp than the s2000. i dont know off the top of my head what the torque figures are, but i bet the nissan(best jap. torque builder) has more specific torque. revving to 9000 is an easy way to make big power, but its also an easy way to waste an engine. i cant wait to see how long those things last.:firedevil did you know that high rpm, way advanced ign. timing, and high comp. are much less efficient(in respect of cylinder pressure) at producing hp than better breathing? two words......rod stressi like to compare specific torques of engines because as the great engineering voodoo man q45tech says it is a much better measurement of efficiency. by the way the 350z is among the top dogs in the specific torque arena and at a very low price:)

[s13sr20chris]

You can't compare two completely different platforms and then say that one is better than the other for just one reason. The discussion was strictly aimed at engines, not complete cars. As far as an RB30 that makes 2000 HP, what if the same engine was a 4 L? The RB engines are very capable engines, but to say that a 5 L engine (no matter the number of pistons) isn't capable of the 2000 HP is ridiculus. As far as rotary engines, they produce power on every revolution, unlike 4 stroke internal combustion engines. So, if you have a 1.3 L rotary turning at the same RPM as a 1.3 L internal combustion engine then the rotary will actually have used twice the amount of displacement as the IC engine. This is why most people consider a 1.3 L rotary a 2.6 L. So as far as a rotary is concerned, they make more power because they displace more air and fuel, which is the same reason why larger displacement IC engines produce more power. Rotaries were developed by a lot more than one company, there was even a corvette with a rotary engine, not many people know about that though.:icon18

personally i prefer measuring disp the regular way(13b is 1.3l). if you go by the whole "amount of air and fuel entering the engine" thing, you end up with turbo engines being large displacement versions of an atmo equivelent. regardless of one power stroke per rev as compared to an otto's one per two revs, disp. is a measurement and not an estimate of air ingested. shoot, if disp. was just the amount of air it sucked in, then it would change according to throttle angle and rpm. we could create a cool gauge that showed disp. calculated from maf voltage. a rotary engine should be considered a two stroke for all practical purposes. yes, it has all four strokes, but it does them twice as fast.

[s13sr20chris]

Well, desiel engines have thier own purpose, but if you had 2 identical cars with identical wieght then that desiel would destroy the rb in an acceleration test. Torque is what accelerates an engine. The RB would have to compensate for it's torque with rpm's, which takes time and means compensation through gearing, while the desiel would have more power at lower rpms, which translates to less shifting, less gearing, and more time spent accellerating.:poke

accelerate harder? well it would certainly pull harder giving a seat of the pants feeling of being a winner in a fast car. however, the looking out the window test will surely stunt the feeling of superiority as the rb flys by. if diesel engines were da bomb f1 would know all about it. same with pushrods and 5 valve(as opposed to 4 valve)heads. when deciding what is really the best its a good idea to check out the unlimited race series. can-am for instance. big engines with or without forced induction but always with technology.

[s13sr20chris]

Enter the Dodge Tomahawk.

http://www.caranddriver.com/ar...=5448

8000cc V-10 500 low tech , two vavle , pushrod horsepower. Good for an ungodly 1/4 mile and 400+ mph!!! You want to test it?? If you still want to get psycho you could always Twin turbo it. then the question is how fast do you want to DIE!!!!

btw it weighs in at 1500 pounds!!! Now that is a power to weight ratio!!!!

yes, that certainly is impressive, but it is also completely useless.

[tl1000sga]

yes, that certainly is impressive, but it is also completely useless.

It's for entertainment and development purposes (mainly), so if it's useless, so is every race car ever built (especially F1 cars).:alcoholic

[MrFox]

we could create a cool gauge that showed disp. calculated from maf voltage.

A BMEP gauge like this would be more useful:

[s13sr20chris]

i really meant useless for a driver. it does serve a purpose though so i accept your point. that is if your point was that i used the wrong word(useless). i could have used pointless maybe. eh, same problem. you get the picture anyway. i dont think the tomahawk compares very well against an f1 car however.

[s13sr20chris]

A BMEP gauge like this would be more useful:

no doubt, but it would not show your engine increasing in cubic inches as you rev it in neutral;)

that is a cool gauge by the way. what is it in? i assume they are using a transducer in the combustion chamber?

[tl1000sga]

Well, no, I would deffinately agree with that.

[MrFox]

The load cell actually measures the thrust load on a reduction gear bearing. So its actually getting engine torque, with the gauge calibrated to display BMEP.

Its off a R-2800 Double Wasp18 cylinders, 46 liters, 2000hp

[s13sr20chris]

ah hah, faciful trickery:)

[Nismo_Freak]

I thought the 787B was a 4 rotor engine...

R26B ... 4 rotor engine.

266bhp per Liter ... got efficiency?

700hp @ 9000 rpms620 lb. ft. @ 6500 rpms

[Nismo_Freak]

You can't create torque from gearing

Umm... gearing in it'self multiplies rotational force... aka torque.

(torque @ engine) X (trans. gearing) X (rear end gearing) = Final Torque Output

In fact the height of your tires and wheels plays a role in the amount of actual torque is delivered to the wheels.

Horsepower is a value of work... or the amount of work to move 33,000 lbs. 1 ft. or 1 lb. 33,000 ft. So in actuality you will have peak acceleration at your peak HP point.

[MrFox]

266bhp per Liter ... got efficiency?

But engine specific volume is not a measure of efficiency.

[tl1000sga]

Umm... gearing in it'self multiplies rotational force... aka torque.

(torque @ engine) X (trans. gearing) X (rear end gearing) = Final Torque Output

In fact the height of your tires and wheels plays a role in the amount of actual torque is delivered to the wheels.

Horsepower is a value of work... or the amount of work to move 33,000 lbs. 1 ft. or 1 lb. 33,000 ft. So in actuality you will have peak acceleration at your peak HP point.

Yes, we all know that, that post was a BIG mistake on my part. Now, can we finally move on from that god awful statement?

[D-UNIT]

Ok I'm sorry to say it and say it again THEY IS NO REPLACEMENT FOR DISPLACEMENT!!! We're not not talking about which ELISE can smoke your moped. Or my hayabusa can beat your harley. Or my Jet liner is smoother than your F-16. We're talking about displacement. Sr20 is good right? Stock trim lightly upgraded (10- 12psi )it could give a v-8 a run for it's money. You guys aren't getting the concept of displacement. Now imagine an sr40 v-8 style. At least 205 hp per bank = a 410 hp engine stock boost. What about a NA KA 155hp stock , a little weak right? Well not really cause in v-8 form , it quite possibly could put out 310 crank hp. That would be pretty good for a 4.8 liter. What about that technology infused , high revving , vtec monster - the S2000's engine!! In v-8 form it would be putting out 480+ hp!! That would be insane output for a 4 liter engine not even souped up yet!! If honda made v8's everyone would cry.

Everybody is four banger , four banger is good. "I smoke low tech factory v-8's". So what!! You ever thought crappy v8s are crappy for a reason. If everyone had a high tech v8s with like 400 plus hp ten times the amount of people would die!! Plus the cost of making them. tech cost money!! Imagine a s2000 w/ a ka in it. It would cost like $18,000 instead of $34,000. By the time we massage 400 hp out of our I4's, our motors would be toast. Why? cause we are trying to make the power v8's make when they are not even trying. You only can soup up an I4 so much until your 10 grand in the hole and a turbo mustang just blew your doors off!! Pretty soon you are going to want a bigger motor. In goes the RB another $10000 later your keeping up with that mustang , but he still wins.

But we're not talking about who smokes who. Displacement is the end all!! Don't believe me?? OK I don't care what kind of gearing you have. It would take an RB26 a whole month to get a ship up to a cruising speed of 25 knots. Then the engine would blow!!! This is what displacement is all about!!

http://www.nissaninfiniticlub....anker

I'd love to see an RB even turn a 100 ton propeller through standing water. The engines I talk about are just examples. I like my I4. Getting turbo soon. Hopefully I can hit a 13.1 at 12 psi ( big deal). But I'm not dissing either. Do what you want.

btw... for $10,000 I could always buy a LS6 with trans and ecu good for 405 hp and 400 tq. NA. And make it fit!!! But that wouldn't be keeping it "NISSAN". *DARN!!!!*

[s13sr20chris]

i think we have established that tech. and disp. serve different functions. disp is kind of a last resort for me. that is unless you get more cylinders. even then, there just gets to be so much darn horsepower that its just over the top. i also like to have engine tech. thats relative in the modern world. rules out pushrods for me. in one manner of speaking there is a replacement for displacement, in another there is not. by the way, i dont know what kind of turbo mustang you are talking about or maybe you havnt heard all the stuff that people are doing with the rb motors. one way or the other i think you may have some misconceptions about this imaginary street race.

[C-Kwik]

Horsepower is a value of work... or the amount of work to move 33,000 lbs. 1 ft. or 1 lb. 33,000 ft. So in actuality you will have peak acceleration at your peak HP point.

No, peak torque is where you will have the fastest acceleration in a given gear. HP is a function of speed and is actually 33,000 lb-ft per minute. So what this means is that even with less torque, at a higher RPM you can be doing more work than having more torque at a lower RPM. I can't think of a simple way of explaining this and proving it. But I can think of an easy to understand example that disproves that peak HP is where peak Acceleration occurs.

You've already agreed that torque multiplies through lower gearing. so lets say for a given motor we make 150 lb-ft of torque at 6000 RPM. With a 1:1 gear ratio, you'ld get 150 lb-ft of torque at the wheels. So the HP would be the same at the crank and at the wheel(leaving drivetrain losses out). This would net 171 HP. Lets cut the gear in half(2:1). So now we have 300 lb-ft of torque at 3000 RPM at the wheels. You have double the torque, but if you plug in the 300 lb-ft at 3000 RPM into the HP equation, you still get 171 HP. Lets take it a step further and cut the gear in half again(4:1). You will get 600 lb-ft of torque at 1500 RPM. Yet the HP still stays the same at 171 HP. BVut we all know and feel acceleration is faster in the lower gears. So if HP remains the same at the wheels, how can peak acceleration occur at Peak HP. In short, it doesn't. Peak accelration will always occur when the most torque is put to the ground. And for a given gear, besically where peak torque occurs in the motor itself.

[s13sr20chris]

right so the value of hp is showing you how to take advantage of gear ratios and reach the engines max potential. i hate to sound like some dorky ricer, but lets talk stereo equipment(just to remain cool, i dont even have a working radio in the b12). nobody buys amps based on voltage(all 12v), current flow, or whatever. they buy for watts of power. the reason is that watts are a measurement of power which is force X rate of force application. this gives you an idea of how much work you can do. work being mass X distance of mass movement. hp is a "unit" of power. thats why people say hp is how fast you can use your torque. in the world of internal combustion engines, you have to do it this way. torque being rotational force and hp being the product/power. in theory, we could dyno cars just for torque and stuff, but it would be really strange to see cars with more torque occasionally losing to cars with less. we would all just have to do the math in our heads to compare cars output.

disclaimer: i have never taken a physics class in my life. i am a college dropout(chemistry major) turned nissan dealer tech. if this stuff is wrong, please correct me because i am spreading it all over the internet. also, i dont mean to try to instruct people who do know what they are talking about(engineer types like q45tech, eswift, mr fox, mayhem j30, etc. you know who you are).

[RobDET]

no that is one of those logic fowls... Because acceleration changes when horsepower stays the same does not mean that acceleration stays the same as HP changes...

The maximum torque is most motors happens before the 5,### rpm cross but some motors are still able to accelerate mutch harder past 5k Scope out the S2000 Dyno sheet forinstance... the torque curve on that car is flat as a pancake (except for the slight jump at vtec) but it is the most obvious case where torque doesn't really increase but acceeration does... BIG TIME

[Onizuka]

there is some other thread with a turbo hayabusa, 525hp out of what, like 1 or 1.3 liters? Thats technology replacing displacement where displacement cannot be added.

[C-Kwik]

no that is one of those logic fowls... Because acceleration changes when horsepower stays the same does not mean that acceleration stays the same as HP changes...

The maximum torque is most motors happens before the 5,### rpm cross but some motors are still able to accelerate mutch harder past 5k Scope out the S2000 Dyno sheet forinstance... the torque curve on that car is flat as a pancake (except for the slight jump at vtec) but it is the most obvious case where torque doesn't really increase but acceeration does... BIG TIME

What you feel is not that there is more HP. But most of us are used to motors that run out of steam as RPM's go up. The VTEC motors don't accelerate a whole lot harder, it just still has enough torque to keep pulling stronger up there than you would have if you shifted to the next gear. A lot of it is psychological. It feels pretty crazy when a motor is still pulling at such a high RPM. But you must also consider that given such a high RPM, if the manufacturer uses a low enough gear so that the shift points in relation to the car's speed is still similar to most other cars, you will get nearly the same torque at the wheels of other cars that have the same HP. And Honda does use lower gearing with their VTEC motors to take advantage of the higher redline. So in this sense, torque is increased through gearing.

Who said acceleration stays the same as HP changes? HP is not a measure of acceleration. It's a measure of work done. So while less torque is available in higher gears, at any given RPM, the higher gear wil be moving the car at a faster speed. Which means it is doing an equivalent amount of work. Think of torque in terms of weight. The more torque you have the more weight you can lift. So you take 33,000 lbs and lift it 1 foot in 1 minute. Gives you one HP. Now take 16500 lbs(half of 33,000) and lift it 2 feet in 1 minute. Both of these are equivalent to 1 HP. While the the second is a lighter weight, you're moving it at twice the speed. This is exactly what happens with a car. While you accelerate slower in higher gears, you do it at a faster speed. HP is more of a measure of how much weight can be moved over how much distance in how much time. Torque is the actual force that moves the car. This is why HP is more important in determining the overall accelleration of a vehicle. It factors in RPM. Consider that 1/4 mile/HP calculators use measurements of weight, distance and time or speed. And none can calculate it based on peak torque alone. A motor can be pushing out 500 ft-lb of torque at 100 RPM and be moving slow. But yet another motor with 500 ft-lb at 5000 RPM will move the same weight at a higher speed and get to the finish line faster. And will have done more work.

If you really want to test this, you can always hook a G-Force meter to a VTEC motor. I guaratnee if you graphed it out, it would look just like the torque curve of the motor.