Dyno?

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... and you tell me I have no idea what I'm talking about? You should study some mechanical engineering before you start talking like that :rolleyes:

Have you thought about different sized engines? Let's talk first about big engines with heavy internals and big cylinders like Dodge Viper. It has ten cylinders each sized about 700cc (or 42.7 cubic inches) meaning it has lots of inertia which needs lots of work to get moving, and you'll be getting tons of torque when that heavy piston is going down and rotating the crank. All its internal components must withstand that inertia and massive explosions, and that's why they are made durable and heavy.
You can't usually rev those engines over 6 thousand rpms if you don't want to destroy them so you set up the powerband down with right valve opening/ignition timing and set up short gearing with enough gears to achieve maximum speed. It doesn't matter AT ALL at which speeds the engine works most efficiently as long as you've got the right gearing to keep it running at those rpms.

Ok that's it, next there are small engines with light internals such as F1 engines with twelve 250cc (15.2ci) cylinders. Those cylinders are small as ones in smaller motorbikes so they can easily get moving to 13000 rpms and even higher, meaning you can't get any low-range torque from the engine, you have to set it up making all real power at high engine speeds using proper valve and ignition timing (again). But still you need to set up gearing short enough you'll be keeping the engine in the power band.

Hmm, the next is engine braking again.. it's true they use it in races and so but the braking power is only about 10% of those massive disc brakes so it doesn't really help brake pads lasting longer, drivers downshift while braking only that they'd able to concentrate on turning and accelerating after braking. You wouldn't believe your senses if you sat down in a race car and saw how hard they brake at every corner at last possible moment or maybe you have already experienced that?
Anyway, engine braking is major help only when you're doing your daily driving and cruising around, it makes your brake pads last longer and helps to get a better mileage.

You're wondering about what is horsepower? Here it is:
(Torque x Engine speed) / 5252 = Horsepower

I've got to hurry right now but just start thinking about those things a little and keep in mind it's only about laws of physics; race car engines, truck engines and bike engines are all internal combustion engines working in the same way, no magic involved. oh and remember to read these carefully:
http://auto.howstuffworks.com/question381.htm
http://auto.howstuffworks.com/question622.htm
http://science.howstuffworks.com/fpte.htm
http://auto.howstuffworks.com/horsepower.htm
http://auto.howstuffworks.com/torque-converter.htm
http://auto.howstuffworks.com/engine.htm
:D :D

Edit: sorry about my illogical way of telling things but i'm really tired right now..
 
Originally posted by Speed Drifter
[BOk that's it, next there are small engines with light internals such as F1 engines with twelve 250cc (15.2ci) cylinders. Those cylinders are small as ones in smaller motorbikes so they can easily get moving to 13000 rpms and even higher, meaning you can't get any low-range torque from the engine, you have to set it up making all real power at high engine speeds using proper valve and ignition timing (again). But still you need to set up gearing short enough you'll be keeping the engine in the power band.

Hmm, the next is engine braking again.. it's true they use it in races and so but the braking power is only about 10% of those massive disc brakes so it doesn't really help brake pads lasting longer, drivers downshift while braking only that they'd able to concentrate on turning and accelerating after braking. You wouldn't believe your senses if you sat down in a race car and saw how hard they brake at every corner at last possible moment or maybe you have already experienced that?
Anyway, engine braking is major help only when you're doing your daily driving and cruising around, it makes your brake pads last longer and helps to get a better mileage. [/B]
Click to expand...
First off, know your facts for a start. An F1 engine has 10 cylinders, not 12. So that's 300cc per cylinder (3.0L V10). Just because the engines are small, isn't why they can rev so high (and 13,000 rpm is much lower than what they rev to, try 19,000 rpm). The reason they can rev so high, is because of pneumatic valve operation. Ever sincce Renault developed this technology in the early 90's, engine speeds soared to 18,000 rpm, from their "normal" previous highs of 13,000 rpm.
And your whole engine braking theory is totally false. If the drivers didn't downshift the way they do (engine braking) then their stopping capacity would be much less. I really don't think you fully understand the concept of engine braking, the way they use it in Formula One. The reason they do it in a straight line, is not so they can focus on the corner, but because you have maximum braking capacity in a straight line, so, it's no surprise why they do that. And I don't know what the figure of engine braking really is, you claim it is 10%, but it really is quite a substantial amount in the aiding of stopping, in addition to those massive carbon discs. Your second claim in engine braking really contradicts your whole theory. If you're going to be stubborn about something, at least be consistent with it :lol: You claim that engine braking only helps you in daily driving by saving your brakes? Well, do you think that in racing your brake pads magically don't degrade? It all ties into a package.

As for your claims about larger engines making their peak power at lower rpms, that's common sense, but thanks for pointing that out anyway, if it makes you feel smart ;) I'm pretty sure I didn't mention large engines in my initial argument, so you bringing them into this discussion is really quite irrelevant ;)

What I was saying is, that in general (not being specific to engine size) that a race-prepped engine (be it a small or large engine) generally makes its peak power at higher rpms than its base engine counterpart. The reason is that you spend more time at high rpms while racing than you do in low rpms, so it's only common sense for the powerband to move towards high-end output than it would be to have low-end torque, like you would want in a road car.
 
:lol: :lol: yes you said it, it all ties into a one big package :p
and I say we're even now, if that's okay with you :lol:

Edit: oh yes most F1 engines are/have been V10s but V12s aren't so uncommon, even V8s have been used but I can't remember now which team uses which engines.. and it's true F1 cars have massive engine braking because of they're producing so much power :lol:
 
I'm not even going to bother anymore. Compression ratio dicatates more of the ability for an engine to provide engine braking rather than pure power.
BTW, what's with all the smilies? Kind of immature and pointless IMO.

FYI: In 1998, the FIA (Formula One's governing body) mandated that all engines had to be 3.0L V10 units. Before then, teams could opt for 3.5L engines, either being V8's, V10's, or V12's. And then before 1990 teams could opt for those same configurations, or use 1.5L I4 or V6 turbocharged units (most teams used the turbo option).
 
If I remember the initial arguement (it was so long ago... :rolleyes: ) it was that torque at low revs is not really that important in racing, but power at high revs is...

Ok...

Torque is very important in racing, because without it the engines would have no power, i appreciate that this was known already but, it's not as simple a relationship as [torque] x [time period]

technically it is the integral of torque with respect to the time period and as such it becomes somewhat more complex... I don't claim to fully understand this myself, but it is important to consider it
however in most applications the two definitions are pretty much equivalent

For example, torque is very important in climbing hills, thus the turbo'd JGTC cars usually fare better than the NSX's on the more hilly circuits. Using JGTC as an example again, the faster more sweeping circuits tend to favour the turbo monsters more because they have a broader, flatter torque curve, yet the power curves will be very similar because the NA cars rev higher...

Power is what counts for level ground acceleration, whilst torque is more important for engine braking... im a little hazy on this one, but what I believe is that if the brakes are applying the maximum force to the wheels (ie just before they lock) engine braking will cause the wheels to lock
so the combined force of the discs and engine braking cannot exceed the overall grip of the tyres, and usually the brakes alone can exceed this limit, so engine braking really is of limited use with cars with high powered brakes, if you look at in this light,
F1 cars dont really use engine braking, there is no inertia in the engine, the flywheel is far too light and the shifting is not manual so there is no clutch control: it's all handled by the electronics-- plus there's not really any time for it to take effect since they stop incredibly fast with G-forces approaching that of a head on crash into a tree at 40mph, altough perhaps not so instantaneous...

Most racing cars rev high because the engines are based on real life versions, normally sized engines because they use less fuel for a start and they are much lighter... so to get the power out of them they need to rev higher. bigger engines produce far more torque per cycle so the rpms can be lower to achieve the same power. For example the British Touring cars are usually 2litre four potters producing close to 300 hp at fairly high rpms (around 10k, i think) using F1 is not a fair comparison because they are not using combustion engines in the conventional sense, for example aided actuation of valves. The JGTC Supras also use a 2litre four potter, but only rev to about 8k... this is becase they are turbo'd, and produce more torque per cycle, thus lower rpm's needed to produce the power...

a note on gearing, short shifting will only occur if the ratios are set up wrong... its not just the box ratios that can be adjusted, there is also the final drive which actually makes the biggest difference overall - im sure you all knew that, but i thought id make sure you considered it...

as for the dyno test itself, yes have it in there, but keep an estimated peak power and torque figure, but reveal the actual values and the far more useful distributions (curves) only after the dyno tests... if people dont want to use it, their loss... its a great tool for finely tuning a racing machine, which i anticipate will become far more important in GT4; no more 'slap on this mod and go and win races' i hope it'll require tinkering of to get the edge this time around....

ranted for long enough i think
 
Originally posted by Griffith500
If I remember the initial arguement (it was so long ago... :rolleyes: ) it was that torque at low revs is not really that important in racing, but power at high revs is...

Ok...

Torque is very important in racing, because without it the engines would have no power, i appreciate that this was known already but, it's not as simple a relationship as [torque] x [time period]
Click to expand...
Yeah I know what you're saying. However I think I came off incorectly. I never meant for anyone to read my post thinking that torque isn't important. What I meant to convey was that generally, making peak power at a higher rpm is better for racing than making power at low rpms :)
 
Sorry about those smilies, I was just so happy back then because of some other things and happened to insert some faces in without thinking about it too much :lol: (like now)
 
P2C, I may be from the land of cowboys and longhorns (If you're from Oklahoma University, you might be hating us by now, since we're Big 12 rivals), but I have seen the car in Gran Turismo 2, plus I seen it online. The Peugeot 406 is very beautiful. It has horsepower numbers in the 190 to 200 hp range, and just by looking at it, you'd think this car was exotic. An exotic sedan, but it is wide-bodied and just sweet to watch zip by. I think if Peugeot came to America with their 406 (the 206 wouldn't be a bad car either), America would have seen a lovely car. Speaking of Peugeot, I seen an orange Peugeot 206 coming from San Jacinto Mall back home last year. So... that's a start.

But if you want a dyno for GT4, it would be a good consideration. It might make the muscle car boys happy, especially the ones who take their American babies out to the 1/4 mile. And while GT4 is a ROAD RACING game, it would be cool to have those. And maybe (remember, I'm not the onling gaming type), some people would offer you advice to tune your car to get as many horsepower gains as possible.
 
I quite like the 406's especially the one in Ronin :D & Taxi 1+2 (French film, although the bodykit was a bit umm to much) But there hardly exotic :lol: (Atleast to Europeans)

Peugeot 206 is an ugly blob imo :yuck:
 
Doesn't low-end torque help initial acceleration or accelerating out of a hair-pin turn? I'm sure there will be a number of tracks in GT4 where you really need to slow down to get around certain turns and this is where low-end torque will help you. You're not going to always be driving at the car's top speed, but you definitely will need that quick acceleration right after a turn to beat the AI.
 
Nope. Low end torque helps when you're not running in the optimal rev range for your car. For most cars, if your revs are too low, you simply change down a gear.
So while coming out of the corner in 3rd may leave you wishing for a bit more torque, being in second gear may be just right.

This is why more gears is better - you have a better chance of having a gear just right for any situation. So low end torque isn't as vital.
 
If we were to see this implemented, it would have to be set up similar to the racing transmission.

When you bought the part (Customizable ECU), the car would tend to be pretty well tuned for most situations, but you would have the option to adjust fuel ratios and dyno your changes, this would allow you to customize the car to your preference. Don't down play the importance of Torque, especially if they decide to add a drag race feature.

You would also have the option to have a shop tune your car which would basically give you an optimal tune for specific situations [Road, Rally, Strip], but it would cost a bit more.

On the other hand, Dyno tuing for all parts would probably be a bit repetative. It would still be nice to be able to see your cars torque curve. Maybe just adding the option to the garage.
 
i was always lead to believe that mid to high rpm torque/power is best for circuit racing. just say you had a turbo car with high rpm power, imagine the lag that you would get coming out of a tight hairpin-watch how the rice boy in his stock N/A civic passes you-well atleast until you hit boost again. what i'm saying is high rpm torque/power is best suited for dragracing, no corners in the 1/4mile, no reason to slow down, you just want every last hp, Nm, kw whatever put to the ground. circiut racng needs a more linear power curve, most tracks arent just straight lines where all out power is needed.
 
The thing is, cars including race cars, have these things called gears. So you can be keeping the car in the powerband at all times. Believe it or not, you can go slow enough to take a tight corner, and keep the revs going, you just drop down to first gear, where the ratio is set to keep the car revving round slow corners if there are any on that track.
 

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