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hi

been wondering few things, straighten me out!!

1- if race cars want their suspension so stiff, so they can control car better, why don't they have a steel rod instead of springs~~ 100% rigid...

2-the idea behind fuel injectors is that the fuel is sprayed into mist form such that combustion is efficient, no?

if that is the case let's say we have a 4 cylinder 1.6l engine, means each cylinder 0.4l....instead of doing that why don't we create sumthing along the line of 10 cylinder 0.16l each ~~...so smaller injectors and more efficient...just make the system high reving~~

3-S2000 is famous for it's weight balance 50:50, handling is good. So isn't stereo sytem in the boot good? balance out the weight~~ like those sky scraper with dynamic counterweights to prevent swinging....so all we have left is to increase more power to overcome the extra 50kg or so~~ but heys, better handling

4-the better the flow of exhaust in turbocharged system the better right? so why do the WRC cars bother to put in exhaust at all...they might as well have a heat shield under the engine bay and remove the pipe all together? free flow exhaust~~

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1) Because the chassis will literally bounce off the track if its not twisted into a pretzel shape.

2) Money, its cheap, people are cheap. People buy cheap before they buy good. Oh, and torque, larger pistons, crankshafts and flywheels produce more torque as not everyone likes a 4000rpm launch

3) S2000's are over-rated, $10k car + $3-4k suspension and tyres = S2000 handling

All weight is bad, removing weight from the front like essential items, batteries and so forth is a much easier way.

4) Carbon Monoxide + carbon dioxide, a dozen other types of poisoning and going deaf.

Edited by MK2
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hi

been wondering few things, straighten me out!!

1- if race cars want their suspension so stiff, so they can control car better, why don't they have a steel rod instead of springs~~ 100% rigid...

2-the idea behind fuel injectors is that the fuel is sprayed into mist form such that combustion is efficient, no?

if that is the case let's say we have a 4 cylinder 1.6l engine, means each cylinder 0.4l....instead of doing that why don't we create sumthing along the line of 10 cylinder 0.16l each ~~...so smaller injectors and more efficient...just make the system high reving~~

3-S2000 is famous for it's weight balance 50:50, handling is good. So isn't stereo sytem in the boot good? balance out the weight~~ like those sky scraper with dynamic counterweights to prevent swinging....so all we have left is to increase more power to overcome the extra 50kg or so~~ but heys, better handling

4-the better the flow of exhaust in turbocharged system the better right? so why do the WRC cars bother to put in exhaust at all...they might as well have a heat shield under the engine bay and remove the pipe all together? free flow exhaust~~

1 - imagine there was NO give at all and you went over a pothole... the top would shoot out the mount

2 - expense/size

3 - if you could lighten the front end of a car to the same weight of a couple of subbies and an amp then that would be a good idea maybe, but you cant

4 - turbulence issues.. but i am quite uneducated in this exacty

5 - Moved to general automotive discussion

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#1 they dont. Its mostly the roll they want to get rid of. But they still want movement so the wheels are in constant contact (grip) with the road. Ridged bars dont do that. Drifters however may as well go the bars.

#2 expence, size, weight, engineering complexity, rev happy no torque, and they have the tech these days to not need to. Look 1.6L engines are making more power than V8s were 30 years ago (obviously stock for stock)

#3 If you went to a concert and the band was standing up the front, but the sound was coming from behind you... The idea of the stereo is to attempt to recreat real life, ie sound from infront of you, such as it would be live and unpluged. As in singers voice up front in the middle, drums up back and spread out a bit, etc etc. If its in the back you just wont get that.

#4 WRC cars still need to be road registered. And in some cases the police have stepped in if they are speeding between competive stages, if the car is just that smashed up etc. Also, can you imagion anti-lag in an engine bay full of wires and hoses?

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hi

been wondering few things, straighten me out!!

1- if race cars want their suspension so stiff, so they can control car better, why don't they have a steel rod instead of springs~~ 100% rigid...

2-the idea behind fuel injectors is that the fuel is sprayed into mist form such that combustion is efficient, no?

if that is the case let's say we have a 4 cylinder 1.6l engine, means each cylinder 0.4l....instead of doing that why don't we create sumthing along the line of 10 cylinder 0.16l each ~~...so smaller injectors and more efficient...just make the system high reving~~

3-S2000 is famous for it's weight balance 50:50, handling is good. So isn't stereo sytem in the boot good? balance out the weight~~ like those sky scraper with dynamic counterweights to prevent swinging....so all we have left is to increase more power to overcome the extra 50kg or so~~ but heys, better handling

4-the better the flow of exhaust in turbocharged system the better right? so why do the WRC cars bother to put in exhaust at all...they might as well have a heat shield under the engine bay and remove the pipe all together? free flow exhaust~~

1. imagine coming into a turn hard under brakes, you hit the smallest of bumps, you bounce off the road, so you've lost 2m of effective braking, and u lock up aswell, going straight not around the corner.

2. no useable torque range. to have any effect u'd wanna hit 15,000 rpm. if you can get an F1 car to pass EPA, let me know :P

3. if you want supreme handling, the sound system is the first thing to go to try and save weight, if you want music, you have it in front of you, except the sub, noises below about 200hz arent directional (i think, lol) aerodynamics and downforce is way better than adding weight/moving wieght for handling. also, weight balance is good, but its not the only thing that makes the S2000 a good handling car, chassis design/setup etc has a big effect.

4. yeh last time i heard they had to be road regiestered (with certain exceptions of course, they have special rego), but other than that i dont see why they dont just run a dump pipe and just end it there....

edit - as for the V10, production/production costs/effort required to put one together as opposed to a 4cyl. you have an extra 6 cylders to drop in, 6 extra rods, and also everything is smaller so its harder to work with, but overall the motor would be heaps bigger IMO, which leads me to my last point... packaging... V10>toyota corolla :)

Edited by VB-
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the first 3 have been dealt with

the 4th one - 1 they have to be road legal (they are production cars - they get them standard from factory, and can only change certain things and only a certain amount

and 2 if there is no exhaust pipe, there is a pressure difference created by the expelling of the exhaust gases, and air will rush in from around the turbo, and try to go BACKWARDS through the turbo - just like nitro funny drag cars, with all there power, still have short exhaust headers for that reason - exhaust coming straight out the head means that air rushes in past the gas backwards into the engine - which is not good

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huumm

1-the first one, well they could strengthten the mount of the suspension, I meant if the car is for track work..so won't be potholes

2-okay second one is well justified...

3-its not about sound quality, more to the handling bit, the subs are light but the solid wood box has considerable weight + the level arm from car cetre to rear end of car is larger than level arm to engine. The weight at the back will help with traction, no?

4-why issit they can use missfire system if its meant to be road legal then

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woops read it wrong (no4)

anyway the missfire system:

what it is, is a system that, on upshifts, retards the ignition just a fraction, so it actually ignites the mixture when the exhaust is opening - thus keeping the turbo spooled up (as the force keeps the turbine wheel spinning madly) and allows immediate power delivery ie no lag

tell you the truth - i dont no

Edited by usherly
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1. might work if you were racing on 100% pure flat concrete.

2. hate to tow a trailer with a 1.6L v10 .

3. need to find out what your weight balance is first. then you need to get it at the right height, and get it centred so it doesn't affect your left/right balance. but you'd be better off relocating current parts to help the balance. then retune your suspension.

4. as ash said, legality, and to maintain power. you will hear people talking about 'tuned length headers'. you need a certain length of exhaust to create a scavenging effect. this syphons the air out of the chamber.

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1) You still need weight transfer. If there is no movement in the suspension, then all tyres will be loaded evenly. Therefore when you go to turn, there won't be enough grip on the outside tyres and the car will therefore want to go straight ahead. When you put load onto the outside tyres, they press down onto the road, and will grip better to help you to go around the turn.

However there is no point for a racecar to go too soft in suspension either, because then the inside tyres will be too unloaded and having only two tyres doing the gripping isn't good.

2,3,4) The other questions have been answered suffiently IMO.

Edited by Thunderbolt
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You still need weight transfer. If there is no movement in the suspension, then all tyres will be loaded evenly. Therefore when you go to turn, there won't be enough grip on the outside tyres and the car will therefore want to go straight ahead. When you put load onto the outside tyres, they press down onto the road, and will grip better to help you to go around the turn.

thats not quite right. the laws of gravity and inertia still act on the car so the outside tyres will still get more load as the force of turning still loads up the outside. however the inside of the tyres will lift off the ground. if having solid suspension meant that all 4 wheels had even loading even around corners the car would literally handle like it was on rails.

4-why issit they can use missfire system if its meant to be road legal then

they aren't registered as road cars, but under a class of sports vehicles. they are only allowed to do limited driving on the road. you can't just pop down to the shops in it.

and the missfire system you are talking about is anti-lag. ash was almost spot on. the system is designed so that at low load (like when decellerating) the timing is retarded so much that the fuel isn't ignited by the spark plug. instead on the exhaust stroke the unburnt fuel gets pushed out onto the hot headers and explodes. this keeps the turbo spinning much faster and means that the car is never running vacuum. they can be setup to run 5, 10 or even 15psi at idle. but when driven on the road they usually change the ecu settings to remove the anti-lag.

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On 4, have you ever heard an engine running without a muffler? Even a turbo engine, at idle, makes quite a noise. Now imagine multiplying that up to 8000 rpm.

As in all things in car design, it's all a compromise.

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A car WILL actually produce MORE power, with the exhaust system COMPLETELY removed (IE Take the headers off)

The huge urban myth though is, it reduces power because you have no "back pressure", which, is total and utter shit.

Go, grab an old school engine (Say a old Corolla) Wack it on the dyno standard, then throw on a well suited "sports" exhaust and retune the car. Then remove the exhaust system leaving only the headers, retune the car. Now, remove the headers, You'll quite happily find, you have more power with no exhaust at all, BUT, you'll have one big head ache!

To gain more power by removing the exhaust, you actually have to dial in a little bit more fuel, AND advance the timing a few degrees.

As for anti-lag: 8% extra fuel. Ignition retard by about 45 degrees, so fires at about 30 degrees ATDC. Cyclic fuel cut to control RPM.

It is NOT the exhaust making the fuel ignite.

As has been said though, no exhaust, = VERY noisy.

Oh and as for the dragsters with exhausts... It's done to move the exhaust AWAY from componentry and so that it doesn't destroy the car/driver/essentials...

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The handling of a stock S2000 isn't that good. It might have a 50:50 weight distribution, but with the suspension geometry the rear tends to break away and do it suddenly.

There are quite a few people on a 350Z forum I'm on that bought their cars with the insurance payout they got after wrapping their S2000s around telegraph poles. Most of them did it the same way. Cornering hard, the tail savagely breaks loose with no forewarning. With the short wheelbase they either spin, or get into a tank slapper.

Even the local mags say that the back end of an S2000 is a mystery. Up until 8/10 its fine, but when you push it harder it starts getting really spooky.

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1-the first one, well they could strengthten the mount of the suspension, I meant if the car is for track work..so won't be potholes

No, but even on dedicated circuits you have ripple strips and other kerbs. And most tracks in Australia aren't dead smooth.

On a street circuit, only a few (at best) are perfectly flat.

And as people have said, ultra stiff does not mean better handling. Its not just drifters use the weight shift that comes with suspension compression to adjust the attitude of the car in and through a bend - racers do it too.

3-its not about sound quality, more to the handling bit, the subs are light but the solid wood box has considerable weight + the level arm from car cetre to rear end of car is larger than level arm to engine. The weight at the back will help with traction, no?

Less weight is still better than more weight with good balance. A stereo isn't a mandatory part of making a car go fast, so pulling it out and relocating stuff you do need (battery, fluid resovoirs, etc) to improve balance is still better than sticking a pair of boxed subs in the boot.

The weight also sits relatively high as well, which increases your centre of gravity.

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