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Discussion Starter #1 (Edited)
this is for all those that have argued with me about how I don't know what a transmission does. I believe the OP on team-integra said it best so i'll just copy and paste his article and he can have the credit for this one...

Begin quote:

I'm going to add this into an article but I figured since there has always been confusion regarding gear ratios and the concept I talk about here isn't discussed much I though I would post it up. Anything you want to add to the discussion is welcome.

Gearing plays a much bigger role in your car's performance than most people realize. Everyone focuses on engine horsepower (peak horsepower at that) and never really pays attention to what gearing can do for your motor. In alot of cases, proper gearing will effect your car's accelerational ability much better than any bolt-on motor modification can.

Why do cars have gears? The major and often overlooked reason is torque multiplication. Most people don't even think about this yet it's one of the most important aspects of making your car go faster with better gearing.

How much torque does a stock GS-R motor put to the ground? About 110 lbs-ft max (estimation). Think of how much force that is. If you have enough leverage you can torque 110lbs-ft on a torque wrench by yourself with your arms. Can you move a car by yourself using that much force? Sure you can, but it's not going to move very fast and it's going to put a heck of a lot of stress on your body.

Your motor is the same way. You could have a silly drag race of two guys pushing one car and another other car that was being powered by it's 110 lbs-ft motor and 1:1 absolute gear ratio and the car that was being pushed would win.

So how do we make a car that has a motor putting out such weak torque faster? That's when gears come in. Gears will multiply the torque by certain factors depending on their size/teeth count. Take a GS-R in first gear (3.23), when the motor spins 3.23 times, the driveshaft will turn once. And for every 4.4 turns of the driveshaft, the differential (final drive, 4.4) will turn once. That is directly connected to the axles which turn the wheels. You can simply multiply 3.23*4.4 to get an absolute gear ratio of 14.212:1. This means for every 14.212 turns of the motor the wheels will turn once. So if the motor gets to turn 14.212 times in order to only turn the wheels once, the amount of torque the motor is applying to the wheels gets multiplied that many times.

Multiply it out, 14.212 * 110 lbs-ft = 1,563 lbs-ft of torque to the wheels. Now does that look better? Yes I think we can accelerate a car decently with that amount of torque.

Different gearing then would have obvious affects on your torque output. Take 3rd gear in a GS-R, and put different trannies on it.

Stock GS-R at 110 lbs-ft max torque in 3rd gear.
Applied torque to the wheels:

GS-R tranny, 1.36*4.4*110= 658 lbs-ft
LS tranny, 1.269*4.266*110= 595 lbs-ft (63 lbs-ft power loss)
Type R tranny, 1.458*4.4*110= 706 lbs-ft (48 lbs-ft power gain)

Gaining power with a different transmission? They didn't teach us that at Import Tuner magazine school. This will of course not be shown on a dyno because they take the RPM signal and roller speed to correct down to a 1:1 ratio to get a clean measurement.

Here is a dyno chart comparing the torque curves of the 3 main stock Integra motors. Pretty much shows what we all know right? LS has the most low end power while the Type R has the most high end power and the GS-R is the middle ground.



This next chart compares the absolute gear ratios of each of the stock Integra transmissions.



Now look at the torque curves again with the torque multiplication of the gear ratios factored in. This example was corrected for 3rd gear, each gear would space the curves differently depending on the multiplication factors but 3rd gear shows a good average. Tells a very different story now doesn't it?



The final drive modification.

A cost effective and completely painless upgrade for both a GS-R and Type R would be to install the JDM ITR 4.785 final drive kit (~$450). There are of course even shorter final drive kits so it will depend on your budget and how short you really want your gears to be. But the 4.785 will put the GS-R at a very close level to the stock ITR gearing, as you can see from this chart comparing their absolute gear ratios.



Now look at what it does to the torque curve in 3rd gear for the GS-R, putting it much closer to the stock Type R.



The 4.785 final drive gives the GS-R a solid 58 lbs-ft torque gain throughout the powerband in 3rd gear for the GS-R.

Now put speed into the equation, and see the difference the final drive plays throughout the entire range of acceleration


So ends the torque multiplication portion of the gearing article, next is powerband and gear ratio relationships. For more gearing information you can check the Integra specifications and Gear Ratio calculator articles under Information/FAQs.

End quote

see the article if you want the graphs...

http://www.team-integra.net/forum/display_topic_threads.asp?ForumID=10&TopicID=38223&PageMsg=Viewing+Common+Topic

and please learn your info before you post here...
http://science.howstuffworks.com/gear-ratio.htm
http://auto.howstuffworks.com/transmission1.htm
 

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Brokedick Millionaire
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You proved you can cut and paste, lets see you apply that info.
 

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Discussion Starter #5
I give up with you guys............ i cut and pasted to prove my point but no one can admit they are wrong. yes the gear ratio multiplies torque. the final drive multiplies torque. he stated exactly what i was saying previously, you will not move your civic with 110 ft-lbs of torque. to me, that is common sense, but yet no one can believe that? i dont understand what argument you have here... how i look like the idiot is beyond me when i have stated this very thing from the beginning but yet no one seems to believe that your gear ratio takes the engine torque and multiplies it.
 

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what do you mean you wont move your civic with 110 footpounds?...i have a stock y7...thats about 103 foot pounds of torque...im sure there are plenty of guys on here with y7s who can provide you with video of there cars actually moving...
 

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Hi hater!
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What he is saying is gears move the car which is no shit and certain gearing will move the car better than others we already know this you dipshit oh god i give up on you why are you still trying to push this shit we know what gears do and that changing ratios will make you quicker and shift your power band once again your a moron give it up. God you cant even put it in your own words copy and paste some more please. You are so schooling us with someone else research come on now. Are you serious Im about to neg rep you for the ignorance and your willingness not understand that we dont care what your saying. You made a completely stupid statement and then got but hurt when we didnt bandwagon you get over yourself asswipe.
 

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COOOOOOL BEAAANNNS
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what do you mean you wont move your civic with 110 footpounds?...i have a stock y7...thats about 103 foot pounds of torque...im sure there are plenty of guys on here with y7s who can provide you with video of there cars actually moving...
the article says your engine is putting out 110 footpounds, but the tranny gear ratio multiplies it.
 

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lol hadnt had my morning copenhagen yet official retard apologies alll around
 

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Discussion Starter #11
oh no, not a negative rep....

cmgreen20, take a torque wrench... set it to 110 ft-lbs, put it on the lugnut and turn, now before it clicks see if you can do the quarter mile in the same time that your car can do it in. heck see if you can do the 60ft in the same time your car will. that is 110 ft-lbs to the wheel and you are telling me that is all your tranny is putting down?

another example:

take a simple dc motor, lets say its torque value from factory is at... 10 ft-lbs. Most likely you will be able to stop that motor from turning.
now run that motor into a gear box with an overall gearing ratio of 100:1. Sure there will be some loss from all the gears turning, lets say you are getting 85% efficiency through the gearbox. for every 100 times that motor turns, the final output shaft turns once. now try and stop that output shaft which given the gear ratio multiplication and efficiency, the output shaft is down to 850 ft-lbs of torque. No way you are stopping that shaft with your hand.

yet another example:

launch in first gear. which has a gear ratio of lets say 3.8... and a final drive of 4.5, lets assume 85% efficiency

110 ft-lbs*3.8*4.5 = 1881 ft-lbs of torque
1881*.85 = 1598.85 ft-lbs of torque

almost 1600 ft-lbs of torque will get you moving like first gear should.

now, try to launch in 5th gear... lets say you have a 5th gear ratio of .83 and again the final drive of 4.5, again assuming 85% efficiency

110 ft-lbs*.83*4.5 = 420.75 ft-lbs of torque
420.75*.85 = 357.6375 ft-lbs of torque

now if you actually launched in 5th gear, you would stall bc the torque is not enough to overcome the coefficients of static friction and get your momentum going, and that is about 350 ft-lbs of torque to the wheels.

however you are going to sit there and tell me the tranny has nothing to do with your torque output and multiplies nothing?

It is you that needs to learn about cars.



Now onto a dyno test. A dyno test assumes no multiplication so that you can obtain the engine torque, not torque through the transmission, which is why they generally will run the dyno in the gear closest to the 1:1 ratio, but then need to offset it based on your final drive. a dyno will give you a number of 110 ft-lbs but that is engine output, not wheel torque through transmission. that is my point.

boosted-ed, i'm glad you can be so condescending with a keyboard, takes a real man. grow up. lets count the number of times you were wrong on this topic...

1
AWD has more parasitic loss than FWD. And multiply through the tranny are you kidding me. Please do a little more lurking a little less posting. LOL @ douche
yes it does multiply through the transmission, learn what gearing ratio is.

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The transmission puts the power to the wheels back to basics for you my boy.Thats why when people ask about power there is flywheel hp then there is actual whp. Wheres Bone when you need him to take this kid back to kindergarden.
power and torque are two seperate things.

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Have you payed attention there is loss its like 25% for AWD and like 10 or 15 for FWD I think thats right. Think about it you think that the tranny will be able to put the same power the engine is putting down with no loss through all the power transfers and gears and shit. Really look up what a tranny does and it will all make sense I promise it will. The motor sends power from the flywheel to the clutch through the case and and then the axels and for awd there is even more so.............where does that equal multiplying power.
again power is not torque. and yes gearing ratio is a multiplication. learn what a ratio is, learn what gears are. please.

4
Im sorry this should be common sense but what your saying and what we are saying are 2 different things lol. You still look like and idiot please give it up. Your not gonna school us on some bullshit that alot of us should know and understand jesus christ you people are too funny always trying to prove a pointless point.
you are right here... a lot of us should know this, but the fact of the matter is you dont. you have no idea what it is.
 

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Resident Gunsmith & Duracoater
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yes gears will multiply your torque....

all they are, really are just toothed pulley's ...

what's this thread for, did someone get some black pearl syndrome....?
 

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Discussion Starter #14
this thread is because some of members on this forum dont realize the difference between a dyno torque number (which negates the gearing ratio and final drive) and the actual torque at your wheel
 

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Hold up did you just make a classic mistake and say that hp is not torque or are 2 different things now I know your just trying to hard hp is a derivative of torque how do you think they get HP lol man give it up your confusing poor noobs there eyes are bleeding and heads are hurting. You just trying to over complicate nothing. Lol I need to find something out haha. I have lots of learning to do and have learned plenty but you sir are teaching nothing. It must suck that for all these years of dyno tuning they have been doing it wrong you have found the holy grail of HP where is your award
 

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Discussion Starter #16 (Edited)
yes i realize they are related... but they are not the same thing...

hp = (torque * RPM)/5252

5252 being a general constant used... not incredibly accurate...

i am a 4th year mechanical engineering student, these concepts are not new to me

torque is the force * perpendicular distance... torque is not work, as the distance measured is perpendicular to movement, not co linear.

work is force * distance, but the distance here is in the same line as the force...



oh a good read for you...
http://www.procivic.com/pages-horsepower_torque/index.html

read "the transmission effect"
 

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yes i realize they are related... but they are not the same thing...

hp = (torque * RPM)/5252

5252 being a general constant used... not incredibly accurate...

i am a 4th year mechanical engineering student, these concepts are not new to me
Now Im glad that you have shown some book smarts but your common sense is lacking Im a self taught engineer and most concepts that I read/see are not beyond my scope of understanding so lets just agree to disagree and realize you said something fucking stupid and deal with it lol still trying very hard. And you contradict yourself. Enjoy the rest of your schooling I hope your not so arrogant there as well hard to learn something when you know it all
 

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Discussion Starter #19
Now Im glad that you have shown some book smarts but your common sense is lacking Im a self taught engineer and most concepts that I read/see are not beyond my scope of understanding so lets just agree to disagree and realize you said something fucking stupid and deal with it lol still trying very hard. And you contradict yourself. Enjoy the rest of your schooling I hope your not so arrogant there as well hard to learn something when you know it all
i'm just curious as to where i have contradicted myself?
 

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