The definitive GT5 transmission tuning guide.

[CSLACR]

What you are saying, whether you know it or not is this:
100lbs of force applied 3,000 times per minute is more effective than 80lbs of force applied 5,000 times per minute.

Quick math
100 x 3000 = 300,000
80 x 5000 = 400,000

So at 3000 rpms with 100 ft lbs, you're generating 300,000 lb-ft of thrust per minute, whereas at 5,000 rpm and 80 lb-ft you generate 400,000 lbs of thrust per minute.

It doesn't take rocket science to know which is more powerful.

 

[grenadeshark]

What you are saying, whether you know it or not is this:
100lbs of force applied 3,000 times per minute is more effective than 80lbs of force applied 5,000 times per minute.

Quick math
100 x 3000 = 300,000
80 x 5000 = 400,000

So at 3000 rpms with 100 ft lbs, you're generating 300,000 lb-ft of thrust per minute, whereas at 5,000 rpm and 80 lb-ft you generate 400,000 lbs of thrust per minute.

It doesn't take rocket science to know which is more powerful.

That's not how we calculate HP, so why would you use that math?

I get what you are saying, but you are ignoring load placed on the engine.

If it takes 100lbs to move something, it doesn't matter how fast your engine is TRYING to spin to create 80lbs of force.

 

[AssassinTuner]

You guys are seriously not even reading what I wrote...

ITS THE EFFECTS OF GEARING THAT ALLOWS A CAR TO CONTINUE TO ACCELERATE PAST THE TQ PEAK.

To answer your question. You are going to do whatever makes the TQ output to the wheels the greatest.

Sorry Dude you seem to miss that HP is a representation of that tq put to work.

The answer is C simple as that. KILLs your theory. It's common knowledge, even automatics let you shut off overdrive to drop to a lower gear for higher rpm & better acceleration for passing.

Downshift to get higher in the rpm's, more hp and more acceleration to make the Pass.

 

[grenadeshark]

Sorry Dude you seem to miss that HP is a representation of that tq put to work.

The answer is C simple as that. KILLs your theory. It's common knowledge, even automatics let you shut off overdrive to drop to a lower gear for higher rpm & better acceleration for passing.

Downshift to get higher in the rpm's, more hp and more acceleration to make the Pass.

Give me your numbers and I can easily show you why your point makes sense. It is because engine TQ output to the wheels via gearing is greater by downshifting.

This is a good quote comparing HP and TQ and their purposes.

Power matters because at any point in time, acceleration is proportional to the rate at which the engine is performing work. Engine torque tells you how much work is performed over any specific interval of crankshaft rotation, but does not tell you how quickly the work is being performed. It is of course possible to deduce acceleration from the engine torque using other information such as the overall gear ratio and wheel diameter, but that doesn’t change the pertinent and useful fact that at any point in time, acceleration is proportional to power. Recall that power is equal to the product of force and velocity. If you turn that around, it says that force is equal to power divided by the (non-zero) velocity. If you substitute that expression for force into the familiar equation that relates force, mass, and acceleration, you get this:

acceleration = power / (mass x velocity) =>

acceleration = engine_torque x 2 x pi x engine_speed / (velocity x mass)

Hence, given the vehicular velocity that is applicable to some point in time, the acceleration that you get, for a given amount of engine torque and a given mass, depends on the engine speed. Of course, if the ratio of engine speed to vehicle speed is given, as it effectively is while the gear ratio is held constant, acceleration will then vary according to the engine torque. (Note that if you plug a set of values into that equation to calculate acceleration, in order to get proper units of measure for acceleration, you need to use lbf instead of lb for the force component of the torque. 1 lbf is the force of gravity on 1 lb of mass: 1 lbf = 1 lb x 32.2 ft/s^2 = 32.2 ft-lb/s^2 = 4.45 N.)

I can't argue with you guys anymore... I am bored at this point. Believe whatever you want and I will do the same.

 

[AssassinTuner]

That's not how we calculate HP, so why would you use that math?

I get what you are saying, but you are ignoring load placed on the engine.

If it takes 100lbs to move something, it doesn't matter how fast your engine is TRYING to spin to create 80lbs of force.

What?!?!?

You don't think rpm is factored into hp?!?!?

Are your serious?

 

[grenadeshark]

What?!?!?

You don't think rpm is factored into hp?!?!?

Are your serious?

Again, I didn't say that. I'm done with this bs... You guys are reading whatever makes your point seem valid and ignoring everything else I say. Continue on with this philosophy. GL:tup:

 

[AssassinTuner]

100 (tq) * 3000 (rpm) / 5252 = 57hp

80 (tq) * 5000 (rpm) / 5252 = 76hp

Getting the picture?

 

[grenadeshark]

Why is it that a big block v8 can accelerate from 1000 rpms like a rocket yet it makes only 76 hp? Because it has 400 ft/lbs of tq, that's why...

Its the effects of gearing and RPM that allow cars to continue to accelerate past their TQ peaks. Yepee. Night.

 

[AssassinTuner]

Moved

 

[grenadeshark]

76hp, from 400tq? Are you okay there buddy?

400 (tq) * 3000 (rpm) / 5252 = 228hp

300 (tq) * 5500 (rpm) / 5252 = 314hp

Getting there yet?


We are not trying to bomb on you. Just clear up an obvious misunderstanding.

Heck, I just came in to toss around ideas about catering gears to specific tracks. Your very obsessed with Tq.

I used 1000 RPM in my calculation, not 3000. I am obsessed with TQ because it is the only thing being measured. Everything else is a calculation based off of TQ.

People throw around HP and it is important to compare. You cannot compare effectively with tq. But, saying TQ has no part and HP is where it is at, its the same as saying you can have wisdom without experience...

It just doesn't make sense. They are factors of each other and represent different ideas. Yes, horsepower equals work over time. Torque is a measure of force. They are both factors of each other.

So what we are really disputing is whether work matters or force matters. I would agree when comparing things, work absolutely matters. When tuning an engine, i prefer to tune via force transmitted to wheels as work is relative.

 

[AssassinTuner]

I used 1000 RPM in my calculation, not 3000. I am obsessed with TQ because it is the only thing being measured. Everything else is a calculation based off of TQ.

People throw around HP and it is important to compare. You cannot compare effectively with tq. But, saying TQ has no part and HP is where it is at, its the same as saying you can have wisdom without experience...

It just doesn't make sense. They are factors of each other and represent different ideas. Yes, horsepower equals work over time. Torque equals force x time. They are both factors of each other.

So what we are really disputing is whether work matters or force matters. I would agree when comparing things, work absolutely matters. When tuning an engine, i prefer to tune via force transmitted to wheels as work is relative.

Why is it that a big block v8 can accelerate from 1000 rpms like a rocket yet it makes only 76 hp? Because it has 400 ft/lbs of tq, that's why...

Its the effects of gearing and RPM that allow cars to continue to accelerate past their TQ peaks. Yepee. Night.

76hp, from 400tq? Are you okay there buddy? Making 400tq at 1000rpm is a stretch. But let's go for it.

400 (tq) * 1000 (rpm) / 5252 = 76hp

I guess your saying it peaks at 1000rpm? Wow... Okay then...

350 (tq) * 3000 (rpm) / 5252 = 199hp

300 (tq) * 5500 (rpm) / 5252 = 314hp

Getting there yet?

It seems it's accelerating as the tq falls because the power is put to use over a range of rpm speeds, as those engine speeds increase so does the acceleration rate. Until the tq fall faster then the rate of gain from increasing engine speed. This is represented as Horsepower. The rate of acceleration increases as the hp increases, then falls as the hp does.

We are not trying to bomb on you. Just clear up an obvious misunderstanding.

Heck, I just came in to toss around ideas about catering gears to specific tracks. Your very obsessed with Tq for no reason. It's not the plain tq figure that's important but HOW it's put to work represented in hp.

 

[grenadeshark]

76hp, from 400tq? Are you okay there buddy? Making 400tq at 1000rpm is a stretch. But let's go for it.

400 (tq) * 1000 (rpm) / 5252 = 76hp

I guess your saying it peaks at 1000rpm? Wow... Okay then...

350 (tq) * 3000 (rpm) / 5252 = 199hp

300 (tq) * 5500 (rpm) / 5252 = 314hp

Getting there yet?

It seems it's accelerating as the tq falls because the power is put to use over a range of rpm speeds, as those engine speeds increase so does the acceleration rate. Until the tq fall faster then the rate of gain from increasing engine speed. This is represented as Horsepower. The rate of acceleration increases as the hp increases, then falls as the hp does.

We are not trying to bomb on you. Just clear up an obvious misunderstanding.

Heck, I just came in to toss around ideas about catering gears to specific tracks. Your very obsessed with Tq.

I rewrote my post a bit. I misquoted the tq calculation. I was talking something completely separate and our numbers just happened to match up. The 76 is just a coincidence.

 

[AssassinTuner]

I rewrote my post a bit. I misquoted the tq calculation. I was talking something completely separate and our numbers just happened to match up. The 76 is just a coincidence.

I reworked it for you

400 (tq) * 1000 (rpm) / 5252 = 76hp

I guess your saying it peaks at 1000rpm? Wow... Okay then...

350 (tq) * 3000 (rpm) / 5252 = 199hp

300 (tq) * 5500 (rpm) / 5252 = 314hp


It accelerates because the hp is rising even though the tq is falling. We knows the hp is based of the tq, we know it's useable because of engine speed & gearing, that is WHY we use the hp, it tells us what we need to know about the Tq as the engine puts it to use.

I'm not trying to be negative.

 

[CSLACR]

That's not how we calculate HP, so why would you use that math?

I get what you are saying, but you are ignoring load placed on the engine.

If it takes 100lbs to move something, it doesn't matter how fast your engine is TRYING to spin to create 80lbs of force.

Yes it is.
http://www.howstuffworks.com/question622.htm

(Torque x Engine speed) / 5,252 = Horsepower
The engine that makes 300 pound-feet of torque at 4,000 RPM produces [(300 x 4,000) / 5,252] 228 horsepower at 4,000 RPM. But where does the number 5,252 come from?

300 x 4,000 = 1,200,000 / 5252 = 228.484386

Quick math
Engine A: 100 x 3000 = 300,000
Engine B: 80 x 5000 = 400,000

So at 3000 rpms with 100 ft lbs, you're generating 300,000 lb-ft of thrust per minute, whereas at 5,000 rpm and 80 lb-ft you generate 400,000 lbs of thrust per minute.

Engine A Makes: 57 HP
Engine B: Makes 76 HP.

400 (tq) * 1000 (rpm) / 5252 = 76hp.

(Just using this as another example)
See above, 400,000 lbs per second equals the same, no matter the rpm, 400,000lbs force per minute is 76 HP.

 

[CSLACR]

I had a car take only reached 30mph in first gear, and due to it's torquey 2.4L a relatively low (2750lb) weight, could best most drivers (the track, of course) off the line with Mustang's.
Why? Because it had tenacious grip for a FWD and got it's power early. At any given speed above 10mph it was likely I had more horsepower than them because my gearing was quicker.
What this means, and this is all this means, is at, for example, 20mph, we would both be cruising at least halfway into gear, and probably be close in horsepower. But I would be running a little over 4100 rpm, and they would only be at about 2900 rpm.

But because the engine's of the Mustang reached a far higher power level, despite an extra half ton of weight on some of them, they would still blow past me right after I hit third gear.

That's an example of how the romoured "torque wins races" theories became prevalent.

A better test would be the Integra's, Civic's, etc. As I could blow stock ones out of the water through first gear, and then right after third gear comes in they fly past.

Edited.

 

[AssassinTuner]

Just for ***** and giggles we can still compare your end results. Regardless of understanding or semantics. We can look at the end results.

Post up a premium car you calculated the gearbox and I'll run it through my tuning tool, see how they compare.

Im up for keeping it positive, even if we get choked up here and there.

My tool is still not finalized, I'm always looking for ways to improve it. If we find a way to do so, awesome!

I'd like to see how CSLACRs methods churn a gear set and compare that too.

 

[CSLACR]

Just for ***** and giggles we can still compare your end results. Regardless of understanding or semantics. We can look at the end results.

Post up a premium car you calculated the gearbox and I'll run it through my tuning tool, see how they compare.

Im up for keeping it positive, even if we get choked up here and there.

My tool is still not finalized, I'm always looking for ways to improve it. If we find a way to do so, awesome!

I'd like to see how CSLACRs methods churn a gear set and compare that too.

I'd be more than happy to change the gears on the CSL if I see anything to improve.
But the Nurb is a pretty straightforward track for gearing, because a change for 3 corners better is always 3 corners worse. There's only a couple real "important" corners on the track, which dictate time more than the little ones combined.

 

[AssassinTuner]

I'd be more than happy to change the gears on the CSL if I see anything to improve.
But the Nurb is a pretty straightforward track for gearing, because a change for 3 corners better is always 3 corners worse. There's only a couple real "important" corners on the track, which dictate time more than the little ones combined.

How about a different Track? Nurb GP/F or Fuji, something like that is good for me. I was thinking more generalized before catering to a Track. Testing at Daytona or SSR7 then migrating to a Track that we can adjust it too. However when we start tweaking for the specific track it will throw off the results by added variables, driving style, adjusting variations etc. Keeping it pre-track-adjusted is for us comparing base calculations, or more the results of the varied methods used.

 

[oppositelock]

Wrong!!!!!

It will accelerate faster at it's hp peak it will tow a larger load at peak tq

I've never drove a car that accelerated slower as it revved higher..

Sorry to interject here, but a car does indeed accelerate harder at peak torque. I suggest playing with CarTest. It's an old DOS program but it works well enough.

http://www.cartestsoftware.com/cartest4.5/downloads/CarTest.zip

It shows both torque at the wheels and acceleration g force in graph form. Sorry, this is the best image I could find. I'd make my own but I can't print a DOS screen to the clipboard. You can see (hopefully) in this example that acceleration tapers off past the torque peak, but we still want to keep it in lower gear for maximum acceleration because to upshift would result in an even greater loss of torque to the wheels.

Great program, very informative. A bit tricky to learn but totally worth it.

 

[CSLACR]

Sorry to interject here, but a car does indeed accelerate harder at peak torque. I suggest playing with CarTest. It's an old DOS program but it works well enough.

http://www.cartestsoftware.com/cartest4.5/downloads/CarTest.zip

It shows both torque at the wheels and acceleration g force in graph form. Sorry, this is the best image I could find. I'd make my own but I can't print a DOS screen to the clipboard. You can see (hopefully) in this example that acceleration tapers off past the torque peak, but we still want to keep it in lower gear for maximum acceleration because to upshift would result in an even greater loss of torque to the wheels.

Great program, very informative. A bit tricky to learn but totally worth it.

Can't see anything.

Anyway, if torque were the driving force at the wheels, which it is clearly not a measure of, shift points would be a looooott lower.

Edit: I copied the link and saw it that way, problem is, your "evidence" is so small none of the numbers can be read.
And:

What you are saying, whether you know it or not is this:
100lbs of force applied 3,000 times per minute is more effective than 80lbs of force applied 5,000 times per minute.

Quick math
100 x 3000 = 300,000
80 x 5000 = 400,000

So at 3000 rpms with 100 ft lbs, you're generating 300,000 lb-ft of thrust per minute, whereas at 5,000 rpm and 80 lb-ft you generate 400,000 lbs of thrust per minute.

It doesn't take rocket science to know which is more powerful.

 

[oppositelock]

Can't see anything.

Anyway, if torque were the driving force at the wheels, which it is clearly not a measure of, shift points would be a looooott lower.

Edit: I copied the link and saw it that way, problem is, your "evidence" is so small none of the numbers can be read.
And:

The "evidence" is the program itself, the image is just an example and I know it sucks. Seriously, use it, you'll see what I'm talking about.

 

[CSLACR]

The "evidence" is the program itself, the image is just an example and I know it sucks. Seriously, use it, you'll see what I'm talking about.

I can't read the numbers. They're to small.
I can't open the download either.
I don't need to see any program, I have all the mathematics involved, and the fact is what it is, no program is going to change the world's physics as we know them, at least not any we have yet.

So you're final answer is that 300,000 lbs of force is more powerful than 400,000 lbs of force?

 

[AssassinTuner]

Sorry to interject here, but a car does indeed accelerate harder at peak torque. I suggest playing with CarTest. It's an old DOS program but it works well enough.

http://www.cartestsoftware.com/cartest4.5/downloads/CarTest.zip

It shows both torque at the wheels and acceleration g force in graph form. Sorry, this is the best image I could find. I'd make my own but I can't print a DOS screen to the clipboard. You can see (hopefully) in this example that acceleration tapers off past the torque peak, but we still want to keep it in lower gear for maximum acceleration because to upshift would result in an even greater loss of torque to the wheels.

Great program, very informative. A bit tricky to learn but totally worth it.

No, it will tow greater amounts lower down, but it will go faster higher up.

I'd use tq more if I were tuning a Dodge Ram to pull a boat or something heavy.

It's partially why trucks (most cases) make sooooo much tq, & f-all hp. Not enough engine speed, They tow a big weight, but go slow.

 

[CSLACR]

No, it will tow greater amounts lower down, but it will go faster higher up.

I'd use tq more if I were tuning a Dodge Ram to pull a boat or something heavy.

It's partially why trucks (most cases) make sooooo much tq, & f-all hp. They tow a big weight, but go slow.

It's because big torque on big engines is usually aimed for low rpm, and more torque equals more horsepower, even at low rpm, so while 500 ft lbs may only be 190 hp at 2,000 rpm, if the engines torque peaks at 4000 rpm, it will have less horsepower at 2000 rpm than 190.
And when your towing something heavy, you can't wait for horsepower to come around at 5000 rpm, you need it to get off the line quicker than a snail.

 

[premhz]

Sorry to interject here, but a car does indeed accelerate harder at peak torque. I suggest playing with CarTest. It's an old DOS program but it works well enough.

http://www.cartestsoftware.com/cartest4.5/downloads/CarTest.zip

It shows both torque at the wheels and acceleration g force in graph form. Sorry, this is the best image I could find. I'd make my own but I can't print a DOS screen to the clipboard. You can see (hopefully) in this example that acceleration tapers off past the torque peak, but we still want to keep it in lower gear for maximum acceleration because to upshift would result in an even greater loss of torque to the wheels.

Great program, very informative. A bit tricky to learn but totally worth it.

All true,who hasn`t felt a car/engine run out breath at high revs?. My real life corolla makes peak hp at 6000rpm and peak torque at 3600rpm,but it feels like it pulls hardest between 4-5500rpm then runs out of breath by the time it reaches 6000 rpm,so chasing the 6300rpm redline is a time wasting exercise

 

[AssassinTuner]

It's because big torque on big engines is usually aimed for low rpm, and more torque equals more horsepower, even at low rpm, so while 500 ft lbs may only be 190 hp at 2,000 rpm, if the engines torque peaks at 4000 rpm, it will have less horsepower at 2000 rpm than 190.
And when your towing something heavy, you can't wait for horsepower to come around at 5000 rpm, you need it to get off the line quicker than a snail.

Exactly.

Also when gearing you trade tq for speed. Fact of the situation. You want to maximize engine tq towing ability, it's at slow speeds. No need to go fast and doing so creates greater stress etc, that's why I said "partially" I hope we don't have to attach an side note with book long explanations on every point made.

 

[AssassinTuner]

Moved

 

[oppositelock]

I can't read the numbers. They're to small.
I can't open the download either.
I don't need to see any program, I have all the mathematics involved, and the fact is what it is, no program is going to change the world's physics as we know them, at least not any we have yet.

So you're final answer is that 300,000 lbs of force is more powerful than 400,000 lbs of force?

Argh. Here's a bigger goddamned picture for you.

See the blue line? That's accelerative force. This is what pushes you back in your seat, and it's the sum result of engine torque, individual gear ratio, final drive and tire diameter. If you were to install a g meter in the car it would output a graph that matches this blue line. In each gear, peak accelerative force coincides with peak torque and declines afterward.

Ah, so why do we rev past peak torque for maximum acceleration? See where the blue lines for each gear cross? This is your optimum shift point. Shifting either before or after this point will result in slower acceleration. THIS DOES NOT MEAN YOUR CAR IS ACCELERATING HARDER AT PEAK HORSEPOWER THAN PEAK TORQUE. It means that you lose less accelerative force by staying in gear than by upshifting. Period.

Thanks for listening.

 

[AssassinTuner]

All true,who hasn`t felt a car/engine run out breath at high revs?. My real life corolla makes peak hp at 6000rpm and peak torque at 3600rpm,but it feels like it pulls hardest between 4-5500rpm then runs out of breath by the time it reaches 6000 rpm,so chasing the 6300rpm redline is a time wasting exercise

Yeah, it runs out of breath AFTER peak hp not tq it feels stronger at lower rpm, but accelerates more higher up. Hence tow more down low, go faster faster up high it feels like less acceleration but it's happening at an increasingly higher speed and this Fubars your "Butt Dyno".

Grab a car in GT5 jump in 4th gear and note your speed at 500rpm increments for the entire rpm range. Analyze the results are you gaining speed faster up high or down low?

I'll tell you now because I've already done it. It gradually accelerates faster until peak hp, then it gets progressively slower. Following the hp curve

You also have to factor in the increased resistance (it would be more obvious if there was no wind/rolling resistance increasing as speed does.

Calculating shift points is trying to leave the current gear as hp falls, and match the hp on the rise in the following gear


What is most important is how this relays to the game. Guess what? The game has a relatively equal rate of acceleration until peak hp then it falls.

Example

Roughly (no .XX) 10mph between 500rpm all the way to peak hp, after peak hp it becomes 9mph, after red line 7mph...

That is not much, but clear results.

 

[CSLACR]

It means that you lose less accelerative force by staying in gear than by upshifting. Period.

So now answer "why".
If you want to believe 300,000 lbs of force bests 400,000, etc, that's your prerogative.
And yes, that's exactly what you have to believe to believe torque "accelerates faster than horsepower"

Fact: Peak horsepower is never less power than any other number, hence the term "peak power".
Yes, some cars are allowed to rev past their powerband, this is true, but it has no relevance to the fact that horsepower is what makes cars move faster than a snail.
A pound of torque is no different than a lb of lifting force and most humans are stronger than 4 cylinder engines as per "torque".
But we can't push a car 110 mph can we? Because we don't have the horsepower. We can't multiply our torque by 6,000 steps per minute, otherwise we would make incredibly fast runners.

Edit: nevermind, if you don't get that horsepower IS torque, with amount of times applied already factored in already, you won't.