Gear ratios, final drives, and torque - Team Integra Forums - Team Integra

Team-Integra.net is the premier Acura Integra Forum on the internet. Registered Users do not see the above ads.
Reply
 
LinkBack Thread Tools
Old 04-16-2003, 10:07 PM   #1 (permalink)
Senior Member
 
Join Date: Feb 2002
Location: The OC, CA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 40
Feedback Score: 0 reviews
Default

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.
__________________
#01-0379
SurferX is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Old 04-19-2003, 07:01 AM   #2 (permalink)
Senior Member
 
BlueTeg's Avatar
 
Join Date: Feb 2002
Location: Margaritaville, AZ
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 3
Feedback Score: 31 reviews
Default


Awesome article!
We really needed something like this to tie in all the engine mod articles into tranny selection.
__________________
94 Civic hatch - 350whp time attack car
92 Civic hatch - Honda Challenge H2
08 Nissan Xterra - daily driver & tow rig
BlueTeg is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 08:36 AM   #3 (permalink)
Senior Member
 
pythonscott's Avatar
 
Real Name: Scott
Join Date: Apr 2003
Location: North Carolina-704
Model: RS
Year: 98
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 7 reviews
Default

Will the 4.4 or 4.785 gear bolt into the LS tranny? And if the answer is yes would the new gearing seem too short whith a 6800 redline?
__________________
When did ignorance become a point of view?-Dilbert

CURVE: a photo essay
2002 S2000 #111
1998 Integra RS
pythonscott is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 09:51 AM   #4 (permalink)
Senior Member
 
Join Date: Feb 2002
Location: Duluth, GA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 0 reviews
Default

Excellent info SurferX!
__________________
Type Arrrrr's are weaksauce!
Eva01 is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 10:33 AM   #5 (permalink)
Senior Member
 
MichaelDelaney's Avatar
 
Join Date: Feb 2002
Location: Late Apexing, YT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 30
Feedback Score: 1 reviews
Default

For the beginners among us who don't understand what a gear ratio is or what a "shorter" vs. "taller" gear means, then please, before you go any further, read http://science.howstuffworks.com/gear-ratio.htm and basic http://auto.howstuffworks.com/transmission1.htm articles.

Now on to the more advanced among you,....

I don't recommend getting a shorter FD than the JDM '98 SPec R's, like an ATS 4.929 FD without getting their ATS gear ratio set and knowing you will move your powerband higher or tune it to get at least 500 rpm more out of it's width.

The linked website shows you the disadvantage of the 4.929 on an ITR stock gear set vs. the ATS complete set.

The role of the FD upgrade is to move up both your rpm landing point after an upshift and absolute (gear ratio and FD multiplied) gear ratio.

Clearly the ATS FD alone does not affect the landing rpm point in their website analysis.

The absolute gear ratio, however, does become shorter effectively zinging you through the powerband in each gear faster. The acceleration g force should improve but you really do want their gear set with it to get the full benefit.

For GSR, ITR, Si engines with powerbands starting at 6000-6300 rpm, the 4.929 FD with the ATS gear set would be beneficial.

Again, this all assumes that you aren't playing around with overall wheel diameter and keeping that at stock diameters.
MichaelDelaney is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 10:51 AM   #6 (permalink)
Senior Member
 
MichaelDelaney's Avatar
 
Join Date: Feb 2002
Location: Late Apexing, YT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 30
Feedback Score: 1 reviews
Default

the other thing you'll notice by looking at the nice powerband comparison SurferX has provided is that the LS people will want to keep the confrontation distance to an ITR and GSR as short as possible. The LS people who beef up their existing powerband will be better off going to 1/8 mile strip races instead of 1/4 mile. The longer the distance, the better chance for the high powerband engines to run you down. They'll be behind early because you have the torque placed at a point that will move you ahead earlier but as the distance increases their gearing and high powerband will catch you in the second 1/8 in a 1/4 mile.

So there are some "smart ways" to challenge your opponent. You really need a database like this of gearing and powerband location for other cars like a Celica GTS, Audi 1.8, Neon, VW, Mitsu/Diamond star, Focus, Nissan Si, and Cavalier, etc. to compare to.

As my prof used to say to me, "pick your battles wisely"...
MichaelDelaney is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 11:59 AM   #7 (permalink)
Senior Member
 
Join Date: Feb 2002
Location: Jal-up-en-ya, CA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 2 reviews
Default

Very Nice, Very important information. I just wish we could get some G2 knowledge with the cable tranny and it's gearing added in there. I've been searching for the last couple of days. But only come up with bits and pieces of info. Good work Josh.
__________________
hUkEd oN fOnIckz wurKded FoR mE!?!
lenguaso is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 12:27 PM   #8 (permalink)
Senior Member
 
MichaelDelaney's Avatar
 
Join Date: Feb 2002
Location: Late Apexing, YT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 30
Feedback Score: 1 reviews
Default

We do have the gear ratio specs of G2 tegs' (and G3 tegs' for that matter) trannies from several sites:

http://www.bseries.net/html/specs/btrannyspecs.php

http://www.g-speed.com/pbh/guide.html

http://hybrid2.honda-perf.org/tech/variants.html

we need the stock torque curves of the gen 2 GSR and b18a (raw numbers).

you can generate the same info.

The gen 1 info will be a bit harder but do-able if people can take the time to dig up the same set of info for the D-series and ZC engines and tranny combination.

this is what we're about... at least that's how I think a forum should be used that is driven by the members...teamwork...members taking the time to do some work to get out the info as a start for useful intelligent discussions about Integra performance and show improvement.

if members like to volunteer some time to do the digging up of "good" correct info and we collect it here (so we don't get 10 people doing the same thing), then sign up and let us know who'll do what..delegate the responsibilities....
MichaelDelaney is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 12:30 PM   #9 (permalink)
Senior Member
 
MichaelDelaney's Avatar
 
Join Date: Feb 2002
Location: Late Apexing, YT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 30
Feedback Score: 1 reviews
Default

we might as well put the FD swap and LSD install "how to" links here as well so we have all the info in one thread...have a lot of depth in this thread going...

http://tech.hybridgarage.com/tech/fd-swap.html

http://tech.hybridgarage.com/tech/lsd/index.html
MichaelDelaney is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 12:35 PM   #10 (permalink)
Senior Member
 
Join Date: May 2002
Location: On GS-D3's, CA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 0 reviews
Default

Really simplified basics on gear ratios.
__________________
The things you own end up owning you. All men are not created equal. The only thing equal are their rights.
neouser is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 12:39 PM   #11 (permalink)
Senior Member
 
Join Date: Feb 2002
Location: Jal-up-en-ya, CA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 2 reviews
Default

Great. Thanks for the links.
lenguaso is offline   Reply With Quote Quick reply to this message
Old 04-19-2003, 12:57 PM   #12 (permalink)
Senior Member
 
Join Date: Feb 2002
Location: The OC, CA
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 40
Feedback Score: 0 reviews
Default

Quote:
Originally Posted by lenguaso on Apr/19/03
Very Nice, Very important information. I just wish we could get some G2 knowledge with the cable tranny and it's gearing added in there. I've been searching for the last couple of days. But only come up with bits and pieces of info. Good work Josh.
We have all the gear ratios including the info for the G1 in the generation specific articles. I don't think we have a dyno of a stock G1 or G2 in our members dyno section though. A G2 wouldn't tough to find but a G1 dyno may prove difficult.
SurferX is offline   Reply With Quote Quick reply to this message
Old 04-20-2003, 08:45 PM   #13 (permalink)
Senior Member
 
Join Date: Jul 2002
Location: Edmonton, AB
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Feedback Score: 0 reviews
Default

I would be really interested in seeing what a LS can do with the Type-R gear ratios.

Is this possible? It would be so cool if you could get gears 1 through 4 from the typeR put on your LS.

I have a very close to stock dyno, only mod is a 2 1/4" exhaust.
__________________
scooby_dooby is offline   Reply With Quote Quick reply to this message
Old 04-21-2003, 01:33 PM   #14 (permalink)
Senior Member
 
MichaelDelaney's Avatar
 
Join Date: Feb 2002
Location: Late Apexing, YT
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Articles: 30
Feedback Score: 1 reviews
Default

The effect on acceleration is noticeable (using objective measures like a stop watch) when you change to a shorter FD despite no effect on the rpm landing point after an upshift.

Again, the performance motorcycle press is ahead of our import scene magazine industry still stuck on chassis dyno racing but that's me editorializing again ....so I'll shut up about that...

here we see the effect of Renthal gear sprockets (in yellow) and a Tsubaki chain on a Yamaha YZF-R1 performance bike [ 998 cc, liquid cooled, 11.8 CR, 4 x 40mm Mikuni CV TB's, stock 133 peak bhp @ 10,000 rpm (headwork,cams, and higher CR have produced 160 bhp N/A version), 74 lb ft @ 8750 rpm brake torque, powerband 7000-10000 rpm, 11,800 rpm redline, 6-speed gearbox ].
The Renthal sprocket is like our swapping of the FD only.

From Performance Bike magazine June 2002, p. 39
The Yamaha YZF-R1 powerband is shown here:



From Performance Bike magazine Feb 2003 issue, p. 55.




For those of you who are new to our site (see Why Peak WHP Can Lie: Transient Response Concept , HP and Torque. Analyzing power curves, Gear Ratio Calculator related articles ) and have not read Performance Bike (great UK rag BTW):

the left graph is thrust curve (units: tractive force in lbs.) and on the right is the acceleration curve (acceleration is the rate of change in speed or how fast speed climbs..the steeper the better...if faster is better in your way of thinking and I think it is).

You trade top speed for higher acceleration. Again, notice that it's compromise...you give up something to gain what you want. Here they gained 100 lb thrust in the first few gears but their 6th gear = 5th gear in stock form. "Extreme gearing gets you to 70 mph (from a standing start nearly as quickly as it takes you to stop from it" says the authors of this article. The time to 60 mph (3.7 sec) was unaffected but the time to 120 mph from a standing start went from 9.8 to 9.65 sec. If you don't think that's impressive then consider a trap speed of 120 mph at the 1/4 mile will get a teg into the 10-11 sec. club and they shaved 0.15 sec. without any power add-ons.

The Performance Bike people analyse thrust, acceleration, and roll-on performance. Roll-on performance is another thing you don't see in import magazines. It's the performance of the car while it's already moving and you upshift (like when you want to pass that 18 wheeler in a 2 lane highway and have to pull out into the oncoming lane with a short distance...your life and others may depend on it). They look at 40 mph to 150 mph time. So while you are moving at 40, how long does it take you to get to 150? They saw a 1.6 sec. improvement in this bike's roll-on performance.

So FD swaps without changing gear ratios does have an effect.

So we've moved from butt dyno assessments (which should be considered Neanderthal dumbing down to all of you who have read this by now), to chassis dyno peak whp (dyno racing dumbing down like Mr Roger's Dragstrip and Sesame Superstreet), to powerband location and peak power combined (you've reached performance high school), and now you've entered Performance College with thrust, acceleration, and roll-on performance added to your TI edumacation.

Let's see who are the fast learners here....
MichaelDelaney is offline   Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
Reply


Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Team Integra Forums - Team Integra forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



User Tag List

Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


LinkBacks (?)
LinkBack to this Thread: http://www.team-integra.net/forum/14-performance/22457-gear-ratios-final-drives-torque.html
Posted By For Type Date
Fourtitude.com - Gear ratios, gearing, power curves. 'Splain me This thread Refback 07-16-2011 10:39 PM
VWVortex.com - Gear ratios, gearing, power curves. 'Splain me This thread Refback 07-16-2011 09:15 PM
Hondaper4mance • Ver Tema - B18C1 Final drive This thread Refback 06-09-2011 11:33 AM


All times are GMT -4. The time now is 10:32 AM.


Powered by vBulletin® Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0
Garage Plus vBulletin Plugins by Drive Thru Online, Inc.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.