MFactory

Note: This thread is for informational purposes only and has been cleared by 98vtec

Hey guys,

a lot of you will have probably spoke with me before, and a lot of you probably haven't and don't even know who I am! lol. Anyways, just to quickly introduce myself. My name is Stephen Yeh, President of MFactory Competition Products, and we have spent the past few years on this forum educating our customers (and potential customers) as to the benefits of gearing, both as an alternative and complementary tool to conventional engine tuning.

one thing that has always stood out among the All Motor and/or Street crowd is that one variable stands at the top of the modification food chain, and that variable is Power. Just a quick look through this forum section, and almost every other thread is about making maximum power from either engine modifications and/or bolt-ons (i.e I/H/E). Rarely does a thread appear which is geared (pardon the pun) towards making he most efficient use of your current or proposed setup.

I understand that in a lot of peoples heads, speed rules, but what I would like to do is differentiate between Speed and Acceleration:

- When I talk about speed, I mean the physical speed that the vehicle is moving at. HP determines the maximum achievable speed (within the constraints of your gearing)
- Similarly, when I talk about acceleration, I mean the physical rate that the vehicle is moving at in order to achieve the above mentioned speed. Torque determines your rate of acceleration

When changing your gearing, in most cases, this means a reduction in Speed but at the same time, an increase in Acceleration, and this is the point where a lot of people get confused and ask us: "How can my car be faster if I'm losing speed?"

The simple answer to this is; Efficiency - Making the most of your current or proposed setup. If you will only ever drive at maximum 120mph, why would you want to have an inefficient transmission that is geared to 170mph?

Not only does this affect your vehicles rate of acceleration, contrary to wide belief, it also affects your fuel economy. Cruising on the freeway for hours on end aside, a DD will benefit greatly from a more efficient transmission setup. rpm is only 1 of several variables that contributes to fuel economy.

So back to the topic at hand, how do we make the most efficient use of our current or proposed setup? The answer lies in gearing, and using the various information and tools available on the Internet to help you achieve the most efficient transmission setup for your application. I can't stress the importance of that last point any further, as just changing your gears will not guarantee to make you faster. If done properly though, there simply is nothing currently available in the multi-billion dollar modification marketplace that can compare at similar cost.

The following information takes a completely different approach to "making power", called torque multiplication. As you will soon see, there really is a Replacement for Displacement!

Ask yourself this, which of the following would you choose (Naturally Aspirated):

1) Big engine modifications to increase power, or
2) Mild, or even no engine modifications, but changing your transmission setup to utilize your available power to the maximum potential

Most people (probably 90% plus) would choose no.1, and for good reason. Make more power and your car will go faster, that's common sense. However, if you are able to balance your top speed requirements with your noise/mileage requirements, for a Naturally Aspirated Motor, engine power takes a very distant 2nd place in terms of putting power to the ground. Let me explain....

Most think the acceleration gain from changing gears is due to the change in rpm and/or shift points. Although this does contribute in a sense (i.e keeping you in your powerband), the main reason why your car is so much faster is because of torque multiplication. For example:

1st Gear Ratio - 3.230
Final Drive Ratio - 4.4

3.230 x 4.4 = 14.212 absolute ratio. What this means is that, for every turn of your wheel, your crank will have turned 14.212 times. From this, we can calculate the total torque produced to the ground:

Absolute Ratio x Engine Torque = Torque to the Ground. This is what you actually make to the ground, not what your dyno graph tells you.

Based on a stock USDM Integra Type-R with 122lbft peak engine torque, the following is how much torque you would gain throughout the whole rev range and to the ground. Engine power does not change.

4.928 Final Drive Only:
1st through 5th = 12% increase. That is the "equivalent" of 137lbft peak engine torque (i.e How much torque an engine with a stock transmission will need in order to accelerate at the same rate)

To take a very extreme example (one that is only used by Rally Drivers, as it tops out around 100mph), let's use a 1.210 5th Gear + 4.928 Final Drive:
When driving in 5th Gear only = 60% increase!

To put this into perspective, what the above is telling you is that in 5th gear, you would have the "equivalent" of 195lbft peak engine torque, and that is without doing anything other than changing your gears. No engine tuning, no I/H/E, a 100% stock vehicle (besides the transmission). The following is a torque comparison graph, as pictures paint a thousand words:

Green Line - 100% Stock USDM ITR
Blue Line - Custom Race Setup, with 2ltr block, Portflow Head, Hytech Header, Skunk 2 Pro 2's, fully tuned with Hondata S300. Cost - $4000+ with supporting parts? + Labor
Red Line - 100% Stock USDM ITR, with 1.210 5th Gear + 4.928 Final Drive. Cost - $900 + Labor



Please note that this is a very extreme setup, and only compares 5th Gear. Other gears will be different depending on the gear ratio. This is only an example to help explain what I've been talking about.

You may also be wondering: "Why does this not show up on my dyno graph, if torque to the ground increases?". The reason why this will not show up on a dyno graph is because dynos are calibrated to calculate torque on a 1:1 ratio (hence why a dyno run in 4th gear gives the most accurate results, as it is closest to a 1.000 gear ratio). They are not calibrated to take into account your gear ratios.

As mentioned earlier though, what will determine whether your vehicle will be faster or not is your application. To put it simply, match your gearing to your application, and you will guaranteed to be faster. Conversely, mix and match gearing that is unsuitable and you may find yourself to be slower.

Here are some online tools that you can use to determine what setup is best for YOUR application:

- Gear Calculator
- Torque Calculator

As to where to get these parts, there are various companies on the market that offer transmission products for your Honda, such as: ATS, OS Giken, Spoon etc etc. The choice is wide, and you are not stuck to one particular manufacturer.

Torque = Acceleration. Torque is your best friend, and engine modifications alone will never get you this sort of increase for the same money. Gearing = NA Motor on Steroids

I hope this article will have given you guys more insight into the benefits that transmission modifications can offer both your stock or modified setup (any torque increases are based off your current torque curve, regardless of what modifications you have done). Any questions, please feel free to ask

Ruben19

great info.
thanks.

logg_frogg

Good read, gearing is def next on my list lol

Makes me want to go play with my thrust curve calculator again!

RagingAngel

Well written and concise.... glad we're an available option for those who have 16As and Honda motors in general - which have always been the butt end of torqueless jokes

BIGTUNA

As always, great products and great tech.

flyrod

IMO the picture you posted is a bit misleading, as is your thread title. Changing gearing does not make more power. Changing ratios to "multiply" torque simply reduces the speed. I've seen tractors move boulders at idle, just because of their low gearing. It doesn't mean there was any more power involved in the process.

http://en.wikipedia.org/wiki/Power_(physics)

Yes, optimizing gear ratios for a particular application is a worthwhile endeavor, but lower ratios are not always better. If you take your graph and plot it relative to vehicle speed instead of RPM you get a more realistic idea of what's going on:



These are the torque curves from dyno runs applied through the different gearbox ratios:



You can see that the lower ratios do have more thrust than a higher gear at the same speed. The lower gears are not available at higher speed though, due to the rev limit of the engine. There's no magic and no free lunch.

JDM_CD7

iTrader: (1)

Do you have any applications for the F/H series transmissions?

logg_frogg

No, there is no free lunch....

But there is a large advantage to be had adjusting your gearing so that you nail the traps at the top of your power band in high gear.

Or in other words maximizing how efficiently you accelerate over a 1/4 mile or even how efficiently you accelerate to your maximum track speed

Like everything else in this game balance is key

MFactory

Actually, the title of the thread, and the graph, is not misleading at all. Infact, if you were to read through the post again, then you will understand the information that is being presented.

Yes, you DO gain power. Power in the form of Actual Torque produced to the Ground. This is the whole point of torque multiplication. You DO NOT gain engine power though, and that is stated in the information posted.

The speed/thrust graph you posted, that just points out the shift in the rpm/speed curve. Of course you make more thrust with a shorter tranny at the same vehicle speed as a longer tranny, as you are sitting at a higher rpm. This is not torque multiplication though, and has nothing to do with the information posted.

With torque multiplication, at the same RPM (i.e engine speed), you are physically making more torque to the ground. The formula/calculations are there to see.

Your transmission exists for one reason, to multiple torque. If it did not multiply torque, and you were stuck with an Absolute Gear Ratio of 1:1, you would not get very far. 122 foot pounds of torque will not push a 2500lb vehicle very much at all.

ahobbs

^^^^^makes complete sense to me. very logical

MFactory

Sorry, I missed your post. As this is an information/tech thread, I cannot answer any sales queries directly on this thread, as agreed with 98vtec.

May I point you in the direction of the Sponsor Marketplace on this forum though, where you will regularly see companies offering performance transmission products

If, however, you are asking for a Torque Curve Comparison for an H22A or F20/22B, if you could provide me with a stock dyno plot, I can post one up for you.

JThrasher79

this should be a sticky at the top and a must read for EVERYONE

changing my gears was the best modification i ever did to my car, it felt like a completely new beast

killerpenguin21

great article.

now if only i could get off my *** and put my 4.9 and 3.07 first in.

STOCK_SOHC_DX

I not shure about making power but, it really seems like a good way of getting good usable power to the ground.

flyrod

This kind of power?

fatboy1185

Well written

0xenocron

Good article Stephen!

MFactory

Thanks for the kind comments guys

Ok, seeing as pictures paint a thousand words, here's something that may be clearer to those who don't like reading 1000 word essays. lol

Before you view the image though, keep in mind this formula:

Absolute Ratio (Gear Ratio x Final Drive
Ratio) x Engine Torque = Torque to the Ground. This is what you actually make to the ground, not what your dyno graph tells you, and is denoted as ATG in the following image:



When I mention power increases, I am talking about the ATG value, not what your engine makes.

00Red_SiR

I like the idea but I'm not sure how much I'd like it in my daily driver which happens to cruise on the highway for long periods at an RPM level that already seems a little high to me. More RPM = more noise and more fuel consumption at highway cruise so I'm not so sure about the practicality for it. On a more specific track car, I would absolutely make the modification though.

MFactory

You could always go the LS 5th route if cruising rpm is really an issue. This will give you the benefit of having bat-out-of-hell 1/2/3/4, and slow-*** 5th

ddd4114

Well, no more energy is being produced, so you're not gaining more power. Changing gears does not change the rate at which work is performed; it just changes the trade-off between torque/thrust and speed.

Example:

Let's say an engine runs at a constant 3000rpm and produces 120 ft-lb of torque as measured by a chassis dyno (which equates to 68.5whp). It's kept in 1st gear, which has a ratio of 3.25:1.

If the final drive is 3.7:1, the wheels are rotating at 249.5 rpm, and we produce 1443 ft-lb of torque at the wheels. If we increase the final drive to 4.1:1, we increase the torque to 1599 ft-lb, but the wheels are only rotating at 225 rpm.

If you go through the math, you're still producing 68.5whp in every case. It doesn't matter if you use engine torque/speed or wheel torque/speed. It also doesn't matter what the gearing is.

This is sort of what Stephen was talking about earlier. Yes, higher engine speeds will require more fuel. However, if you have more torque multiplication, you don't need as much energy to produce the same amount of torque. Therefore, you can use less throttle, and fuel economy may improve. It's not a guarantee though.

MFactory

ddd4114: Yes, you are correct in that sense. Instead of saying that you "gain" power then, it could instead be rephrased to "produce" more power (as in torque to the ground). You are also correct in pointing out that whp remains constant regardless.

If this point has confused anyone (which I don't think it has, as flyrod was talking about something completely different), then I apologize

ddd4114

Yup, I think it's just a matter of semantics.

Power = The rate at which heat energy is converted to kinetic energy, which is independent of gearing
Torque = Force performed perpendicularly to a moment arm, which is dependent on gearing
Thrust = Force performed on the road, which is dependent on gearing and tire size

Power = (Thrust)(Vehicle Speed) or (Torque)(Rotational Speed)
Torque = (Thrust)(Tire Radius)

There are conversion factors, but that's the basic idea.


EDIT: Oh yeah, I forgot to include gearing, which is sort of the point of this thread...

Wheel Speed = (Engine Speed)/(Gear Ratio * Final Drive)
Vehicle Speed = (Engine Speed * Tire Radius)/(Gear Ratio * Final Drive)

jlude90

i've tried to explain that higher low gears will produce better fuel economy, but nobody really wants to believe that something that can make you faster will also give you better fuel economy, but its similar to a lightweight flywheel. you're not having you use as much power to turn the flywheel, so more power is put into actually moving the car.

i personally can't wait to try a big *** final drive, i'm thinking about a 5.15 with an F 5th and maybe an F 1st, and this will be monumental in me achieving my goals. the H gearing market is pretty small, but there is still a standout company in my mind that is at least giving us some options and seems to be a large part of the honda commmunity

logg_frogg

I think this pic says it all! You sacrafice top end speed to gain more torque...

The trick is to cross the finish line before you run out of gear.. but to have as little left over as possible