scmil95eg

Link to one of the best articles I've read on the topic:
http://web.archive.org/web/200805270...om/tqvshp.html

gnarlycs

Wow that was a great read. Thank you.

However, one thing that I'm still confused about after reading that is why does (for example) my car only read ~85 ft-lbs on the dyno when the engine is rated for 103 ft-lbs (taking into account the 10-20% loss from drive train). According to that article I should be seeing like a bajillion ft-lbs of torque after my transmission in like 1st or 2nd gear.

94eg!

iTrader: (2)

Gearing is kinda factored out because dyno's directly measure the "power" produced to accelerate a known mass (roller) and then translate that into torque based on measured engine rpm. All that is after any gearing loss (your 10-20%). And of course there is different amounts of loss in each gear. So dyno readings vary depending on what gear you run in. And from what little I've read, you get more loss on a dyno in a lower gear making low-gear pulls very inaccurate.

rs250nut

On the other hand, if you want to win races you will want to make torque higher in the RPM where RPM acts as a multiplier to make horsepower.

This= Win

lostforawhile

you are forgetting the old A20 Accord engines, same thing, all torque lower in the RPM range and more torque then horsepower.

94eg!

iTrader: (2)

If peak horsepower happens below 5252rpm, the motor will ALWAYS make more torque than horsepower. It's not a trick of tuning. It's simple math. It's nothing special or even worth thinking about. All it means is the engine cannot breath.

Horsepower = (Torque x RPM) / 5252

Kozy.

Torque at the wheels, and how long you can maintain it is the only thing that matters. Torque at the flywheel gives you an indication of how much torque ATW, but not for how long. Power does. It's simple.

Everyone's familiar with the old saying 'Horsepower sells cars, torque wins races'. Well it's rubbish.

I prefer 'Horsepower wins races, torque is touted by diesel drivers desperately trying to justify their tedious mode of transport.'

DougNuts

It's not that simple, at all.

I prefer cars with torque - which have won me races against lighter cars with the same HP.

In the end, it's about application (ex. DD, drag car, road race, auto-x) and vehicle weight. I believe torque is more fun in a daily driver.

Twenty47

this.



this thread has made my head hurt. any motor that makes more torque than hp is just not being revved past 5252 or it cant breathe past 5252. torque is made by displacement. thinking a honda engine should have more torque is retarded. the longer you carry torque the more hp you make and the faster you will be.


look at powerful built v8's they always have big gaps between the two as well.. the further you rev the bigger the gap gets mathmatically. 9k rpm ford small blocks look just like our graphs but they have more torque because the engine is bigger.. look built ls7 na graphs. same **** 700+ hp and 5xx torque. how is that different than making 320/220?

beecee18

I've been watching this thread to come up with one simple conclusion.

We are all here to choose this Company's vehicles they produced as our hobby/joy/passion

This is because of Honda's great engineering feats, wether that be the type r program, introduction of varible valve timing, most NA power per liter/fastest piston speeds, whatever it may be.

Never once have I heard an enthusiast ever question these feats which still practically dominate the competeing competition for the last 15-25 years. We are blessed with the these engines/vehicles even in stock form, let alone the aftermarket support, and ability to pull so much WHP, yes I said HP out of this product, expecially All Motor. This is an insult to the members here, aftermarket R&D guys, and Mr.Honda himself. He's probably turning over in his grave to hear $#!T like this.

It seems OP is just a fresh wyotech, UTI, ASE ***** who is not opening up his mind to this specific product, and is stuck in generic ASE domestic land.
I cant believe the bigger names I've even seen in this thread even give the time of the day to explain the unique characteristics/math our hobby/passion is capable of producing, all numbers aside.

For this OP,

http://www.youtube.com/watch?v=5hfYJsQAhl0

Natural Aspirations

^Like!

rich7777

That is f#cking funny

94eg!

iTrader: (2)

^Lol, but that's mean. He just doesn't get it.

ALL MOTORS MAKE TORQUE. How much depends on displacement and aspiration (as already pointed out). What rpm that torque is produced is what determines POWER. Power = WORK. An electric motor can generate 1000lb/ft of torque at ZERO rpm and consume massive amounts of electricity in doing so. But if the rotor shaft still isn't able to turn, it ISN'T EVEN PRODUCING 1 SINGLE HORSEPOWER! NO WORK IS BEING DONE!!!!! Your engine operates under this same principle.

NE Ways. Your just confused. Yes you want to add torque to make your car go faster. The reason that happens is that more power is created at the given rpm. It's just symantics, but the principle is pretty important for you to understand.

Why is it important you ask? Because if you sacrifice that high rpm power just to gain bottom end torque, your car WILL be slower. This is because you are producing less average power. The best example is comparing an B18A to a B18C. B18A has slightly more displacement and generates more torque at a lower rpm. Yet it is considerably slower when placed in the same chassis. Even compare a stock B20B/Z to a B18C. B20 makes a lot more torque, but a lot less power. Therefore it's considerably slower in the same chassis.

Now lets look a the B20 a little more. It has a lot more potential IF you can build it to breath in the same rpm as the B18C. In this case it will be quicker than all motors previously discussed. Not because it makes more torque (roughly same peak torque as stock B20), but because it makes that same torque at a much higher rpm......thereby making more power. This allows you to gear much shorter and multiply the same torque at the same speed. Suddenly your winning.

DougNuts

I'm not the least bit confused, I understand it quite well and I understand your (good) examples. In a daily driver, I don't want to rev to the moon, which is why I like to maximize the power below 5-6K RPM. If I were building a real race car (there's that application issue again), sure, I'd want more HP and a 9K RPM limit.

The OP is exactly right, in a daily driver, torque feels good. If I never rev over 6K RPM (maybe I'm just getting old), then why do I care about how much HP it makes past that?

Edit: I'm just saying that in my Civic, I would prefer 20 more lb-ft below 5K than 20 more hp above 7K RPM.

beecee18

Then I simply suggest that you guys find an application that best suits your needs, SRT4 perhaps, Powerstroke deisel LOL. I am by all means not in a fit over it, I just simply waited through 3 pages of definitive explainations from those who should not have wasted thier time when OP's responses only consisted of still not agreeing/understanding???

And correct me if I'm wrong,
The only thing I have came across in my life that never lied,
was numbers!
So we use those for a reference for our goals!

He just needs to read up on general internal combustion engine theory and design more, or realize a different application would suit him better.
You know Powerstroke

DougNuts

That makes no sense. I'm talking about application for said Honda, like road racing, autox, daily driver, drag racing. If you were to do a lot of highway driving, you may not want a B16 transmission....that's what I mean when I say "application."

You're right, and the guy who posted in post #21 has the numbers I'd want in a daily driver. I like loafing at low rpms with lots of torque and I think that's what the OP is trying to say. Surely some other people here can understand that.

Edit: An engine with good low end torque is going to be more "flexible" to use industry verbiage.

Look up almost any Civic Si vs. GTi comparisons and you'll see what I'm talking about. However, you don't need to have a small turbo to get that low end torque and flexibility - it can be done N/A out of a Honda engine.

http://www.caranddriver.com/comparis...mparison-tests

beecee18

For your first paragraph: we are posting in the all motor section of this forum I hope you know, so the people posting here mostly consist of guys swapping info, sharing builds/power secrets ect. pertaining to built NA setups beyond stock variants. So maybe the section of this forum that pertains to your car will be more suitable for your ultra-conservative style which I respect. cause damn I though I was becoming a sap with age.

Paragraph 2: Did everything these knowledgeable folks say just blow over your head, the mathamatics, physics, do you think they were lying about any of it? Why do you not realize these laws of physics are not correctable/adjustable by the user in the ways you would like. Its like your not happy with the product, and you think that your vision would be better then that of a reputable automaker that spent a $#!T-Ton of money developing.

Paragraph 3: I wish you were in cali, I'd be asking for your crack connect for sure, must be bomby stuff, as if you didnt read the earlier posts, its not how physics works in this situation.

And my last comment of this thread
look at the title of the thread that was put here in the all motor forum?!?!
Why do we care about horsepower in an automotive forum???
I'd like his crack connect also, maybe a little better.

Kozy.

You know what, I totally agree with you on this point. I'd love another 20-30lbft below 6k in my Accord. Since it produces 160lbft at 6700rpm, it really shouldn't be that hard to get at least 150lbft from about 3k. Currently it makes around 120-130lbft, which does admittedly make it feel like a smaller engine than it really is...

In a drag race though, it's only going to make a difference in 1st gear. After that it's all down to the top end power.

DougNuts

Conflicted much?

It's very possible to build and tune a N/A motor with an emphasis on maximizing low end torque at the potential expense of high RPM HP. Do you disagree? You seem to be telling me that it's not possible.

You can keep trying to pick apart my post, it doesn't change the fact that I understand what the OP is talking about. I see it in here all of the time, people asking why their B18 drops off at 180hp@7500rpm and asking how to rev higher to make more HP, while their torque is sitting down at 125 ft-lbs. Yes, getting another 1000RPM of usable power will make more HP and the car will be faster. But, tweaking the cams and timing for another 20 ft-lbs will make the car more fun around town, increase throttle response and generally make the engine seem more 'flexible'. Perhaps this is lost on the racer and ricer crowd.

I understand math/physics, I have an engineering degree. I understand area under the torque curve, my other car has 395 ft-lbs.

I'm also in my 30s, I don't like buzzing down the highway at 4000RPM, so I'll stick with long ratio transmissions, OEM-like redlines and build/tune my motors for idle-7000rpm power. Is there no room for that in the Honda community? Is it only racers and ricers?

beecee18

raverx3m

iTrader: (1)

dognuts you seem like one stubborn guy.

you dont understand still or refuse to accept that theres no torque in a 1.8 motor...

i rather make more power on the top where ITS MOST USEFUL.
than sacrifice all my power to produce some midget torque increase in midrange or low end.


let me AXE you if you have a type-r with 9000 red line why the F would you not use that and only limit yourself to 6000 rpm to gain a bit of low end torque.

if someone wants to race or if you need to accelerate then downshift into lower gear and get up those damn rpms...


again you make no sense why would i sacrifice power to gain low end torque in an engine thats NOT BUILT FOR LOW END TORQUE...

DougNuts

I get it perfectly well. By increasing torque at a given RPM, you've thereby increased the power. Does it make more sense if I worded my statement "Due to what I use my car for, I want X amount of HP at 3000RPM."?

Edit: raverx3m - read post 21, that's all I'm talking about. I like those kind of powerbands over a 200hp but 140tq powerband, simply for the feeling of power everywhere and not having to rev this **** out of it to make power. Different strokes (no pun intended) for different folks.

Twenty47

Doughnuts you need a k series. Max torque at all rpms due to vtc gear.

My stock displacement k24/20 made peak power at 9400 rpms but made 200+ torque starting at like 4k rpms

DougNuts

I know man, with the K-series, it really is cake and eat it too. I don't have that kind of coin right now.....to many hobbies.

Edit: I did have a K-series Accord, but Hondata never came out with a way to tune it, so I sold it for my current toy.

beecee18

What he is failing to understand is the characteristics from the factory of power/torque output. Hes says its a confliction of my two statements above which it is not. That is because we rely on these characteristics and just try to add to them as much as possible in as many places possible within the limits it can, controlled by physics, and the mechanical limits of the motor.

He just thinks he can throw 20 here, take 20 there, and chop 2,000 of the rev here.

Its just not how it works, its already a finely tuned peice that we can only add, and manipulate in ways that dont interfere with the rev/power output characteristics of the engine. We dont want to, and cant manipulate the curves as much as he would like.

A new engine would need to be designed for his wants.

Stubborn is an understatement!