right guys and girls.

Magna Gear ratio's
1st - 3.789
2nd - 2.057
3rd - 1.421
4th - 1.000
5th - 0.731
Diff - 3.684
200km/hour 5th gear approx / 5000rpm

XR8 Gear ratio's
1st - 3.38
2nd - 2.00
3rd - 1.32
4th - 1.00
5th - 0.68
Diff - 3.23
200km/hour 5th gear approx /4200rpm

ok, now the technical question.
a) IF i changed my manual box diff and gear ratio's to match that of the falcon's would that mean i can get the same cruzing rpm as the falcon. eg. 200km/4200rpm?

b) if say we lengthened 5th gear again, to say around .611 would this further decrease engine rpm at the test 200km/hour to say around 3800rpm?

c) providing the torque can pull the car, is my theory right (changing the ratio's to decrease rpm)

d) does anyone have a program which can caculate this kind of stuff. cos ill be looking at short 1st (3.99) making 2nd slightly taller (2.95) third slightly taller again (1.29) same as the falcon 4th gear (1.00) then lengthen 5th (6.11)

what do you guys reckon?

BOoya

your the dude developing all this stuff....shouldnt you be telling us?

haha i'm confused .. check out http://auto.howstuffworks.com/transmission.htm and http://auto.howstuffworks.com/gear.htm

Yeah booya...you're theory is right.

Are you planning on building a custom gearbox?

Yeah booya...you're theory is right.

Are you planning on building a custom gearbox?

I agree with ^^^

THEORETICALLY = SOUNDS ABOUT RIGHT
FINANCIALLY = GOOD LUCK PAL :)

[quote=MagnaLE]
FINANCIALLY = GOOD LUCK PAL :)

why?

cant i pull the guts out of my 5speed to get new gears made?

you could yes - but thats still gonna cost a fair bit of money isnt it??

i donno.. thats why im asking :lol:

booya just bec u live in asp dont need to rub it in u need solutions about how to cruise at 200kmh :lol:
and you have 19 in rims i believe, prolly a larger rolling diameter than stock, so your gearing is already higher,
but changing final drive on a fwd is not as easy as it is on a rwd where you just need to change over the diff centre. adding a gear into the box that is much bigger or smaller than the original might not mesh properly- and that is if you can even get one.
onet possibility though is on the autos the 3.5 has a slightly higher final drive than the 3.0 so it may be the same case with the manuals but i doubt it. best check with a few gearbox specialists if there is any alternative higher final drive gear that can be used, or if you can get a custom one made.

i thought u were building the car with the main aim of faster drag times, higher gearing will ruin that

Booya, you'ld be better off changing the final drive ratio, i.e the diff ratio...this will keep the spread even between gears and not have a large final jump

it would be a prick of a job, but easier (in theory) than changing a specific gear ratio.... its still a major job!! and won't be cheap

[quote:12fa2ad2f6]i thought u were building the car with the main aim of faster drag times, higher gearing will ruin that[/quote:12fa2ad2f6]

yes, first, second, third gears would be adjusted for pure accelleration, 4 will be the mix of city cruzing/accelleration from 3rd and 5th is just pure cruzing 8)

Magna Gear ratio's
1st - 3.789
2nd - 2.057
3rd - 1.421
4th - 1.000
5th - 0.731
Diff - 3.684
200km/hour 5th gear approx / 5000rpm

ok, now the technical question.
a) IF i changed my manual box diff and gear ratio's to match that of the falcon's would that mean i can get the same cruzing rpm as the falcon. eg. 200km/4200rpm?

b) if say we lengthened 5th gear again, to say around .611 would this further decrease engine rpm at the test 200km/hour to say around 3800rpm?

c) providing the torque can pull the car, is my theory right (changing the ratio's to decrease rpm)

d) does anyone have a program which can caculate this kind of stuff. cos ill be looking at short 1st (3.99) making 2nd slightly taller (2.95) third slightly taller again (1.29) same as the falcon 4th gear (1.00) then lengthen 5th (6.11)

BOoya

a) Yes, if the ratio is the same and if your car has the same Coefficient of drag as the Falcon, and if your drive line is the same then you will be doing the exact same speed and same RPM, however, i would think that our Magnas are better in Co.Drag and because it's FWD, you should be doing that speed at just a slightly less RPM.

b) Possible but at that stage, you've got very few Teeths meshing and you'll need very strong material to make the gear hence VERY $$$

c) Right

d) What exactly are you wanting to calculate? road speed? ? ? ? There's a lot of other stuff that will come into it. I found in the past, to get an understanding of all these ratios, play games that allow you change your gear ratios, I would suggest "V8 Challenge".


For a Drag car's perspective, I think what you have in mind will work good.

For ppl who are unfamiliar with Gear ratios, it's the number of teeths of the output gear divided by the number of teeths of the input gear. So a 1st gear ratio of 3.789 means the output gear has 3.789 times more teeths than the input gear, meaning that the input gear needs to spin 3.789 times in order for 1 output rotation, The Idea is that the bigger this ratio, the more torque is produced at the output, hence better acceleration, however, this also drops the MAX speed at that particular gear. Ultimately, there should be different gear ratios for different events. For Drag, Have 1st to 5th all running high ratios. For Economy, have low ratios.

Changing Diff Ratio may sound like a good idea, but not really! as your car is still a road car, you don't want the diff ratio to affect every single gear. think about it this way, by changing the diff ratio lower, you'll increase the MAX speed of your car, but you will rob your self of torque at take off. And the vis versa, rising the diff ratio will lower your max speed, however increase torque through out every gear...

Please correct me if i'm wrong.

if anyone is intrested in a BRILLIANT write up by Raymond_C on the MOGWA forums in regards to this issue go here:
http://www.mogwa.org/forum/phpBB2/viewtopic.php?t=4074


here is the best bit!! if i had the XR diff of 3.23 and the 5th gear of 0.611, and the booya mobile could pull the car right to 9000rpm..

they the theory is the booya machine would blast its way into the sunset at 498km/hour!!! :shock: :shock: :shock:

Fastest magna in Oz perhaps ;) heheh.. well hows this!! using his tools and theory, the above situation at 6000rpm, would see me bolting across the nullaboure at 320km/hour!!! WEEEEEEEEEEEEEEEEEEEEEE!! go the booya mobile!!!!!

http://www.mogwa.org/forum/phpBB2/viewtopic.php?t=4074

You might need to boxes dude. One for regular driving and one for the drags.

in the simplest and least words possible

booya you're an idiot

ihere is the best bit!! if i had the XR diff of 3.23 and the 5th gear of 0.611, and the booya mobile could pull the car right to 9000rpm..

they the theory is the booya machine would blast its way into the sunset at 498km/hour!!! :shock: :shock: :shock:

F

you think your cars internals are going to handle pulling all the way to 9000RPM to get to your sunset speed of 498km/h??

There is a difference between how fast you can go and how fast you can get to that top speed.

By the sounds of it, you're after Top speed, not acceleration. What's the point if you can travel at 400km/h but it would take you 1min to get from 0 - 400km/h. Where as someone else drives a car of top speed of 200km/h, but can get from 0-200km/h in 20sec, which would you perfer?.

here we go :roll:


i was merly point out that IF this was that and that was this, this is what i could get.

where did i say i was GOING to do that and this.

now, for everyone's info, and after about an hour talk with dallas, we have decided to change the centre diff ratio ONLY, and it would be something to the tune of 3.1. internal gear box ratio's will remain as is.

please dont flame me for oviously stupid reasons. :roll: 400km hour. yer right. thats not accounting wind resistance and areo dynamics of the car, not counting no evniromental variables. nothing.

so dont go all out attack on booya cos i had a 'theory' of doing 400km/hour :roll:

in the simplest and least words possible

booya you're an idiot


and what's the go with this man? :-k

:roll:

your comments were rediculous. and now your retracting from them saying that its not possible. Why post them in the first place when you know its not possible the whole time.

the whole assumption of top speeds was made on the "Basis" "That" this and that equals this.

it was pointed out, and in theory IS possible but seriously, if you thought i was gonna acheive 400km/hour - your the idiot

mate, im not here to make fools of anyone, nor am i here to make a fool of myself. but if you couldnt see that the whole last post in reference to the "400km/hour" claim was based on
a) theory, and theory only
b) the fact it couldnt be done anyway

then mate, your lost. very lost. i dont want to make enemies on this forum and i have nothing against you, but you need to think "outside the square"

Ben.

lol

thing is soon as you copped shit for your comments you said.. "oh but it isnt possible because of air resistance, etc." also stop trying to make the situation better for yourself. You originally said 498km/h.. thats a lot more than 400km/h.

If it was so easy for a street drivable car to get to that high speeds without rediculous power outputs why dont any cars do it? Not even the blitz r34 skyline which is tuned for top speed is capable of such speeds and your car is a long way from anything like that.

i've noticed you always say things then end up not getting anywhere close to them. Don't bring up total absolute bullshit like you always say on here coz unfortunately some people actually believe it and think it really is possible when its not.

mate get what you say urself right before calling others lost. by the sounds of it you need to be put into a square coz your thoughts are all over the place.

Your kind of missing the point tjexec. Booyas only hypothesising. I've noticed that sometimes on this forum, if someone puts forward a "theory" or lateral approach to a problem, then they are inundated with insults from people that for some reason arc up over these suggestions.

I agree with you that 498km/h is rediculous (for one thing, I think the panels would peel off and the tyres explode!) but that's the point, it's a joke. :lol:

I wouldn't like to see it get to the point where we need to have a degree in mechanical engineering before we are deemed worthy to comment or put forward theories.

studying mechanical engineering for a year and now industrial engineering good enuf?

all im saying that alrite it was hypothetical but it was completely rediculous. alrite if you put claims of 300km/h being possible thats reasonable. But he practically said 500km/h! Supercars are only now starting to brush on 400km/h. THeres no way a magna could do anything close to that unless it was completely re-designed aerodynamically and mechanically beyond that of million dollar vehicles which basically makes it no longer be a magna.

Big difference between hypothetical claims and rediculous claims

if everyone flew claims as stupid as these around the forums i guarentie you we'd all drop a few iq points.

a) Yes, if the ratio is the same and if your car has the same Coefficient of drag as the Falcon, and if your drive line is the same then you will be doing the exact same speed and same RPM, however, i would think that our Magnas are better in Co.Drag and because it's FWD, you should be doing that speed at just a slightly less RPM.


Ok, I don't get this.. what has Cd got to do with it? Cd is going to affect how fast he gets to that speed and indeed whether he can obtain that speed, but road speed is surely a direct result of how fast the wheels are turning (assuming there is no wheel spin). If your wheels have a circumference of 1m and are rotating 55 times per second you are moving at 55m/s.

[quote:9f9d87bcce="WhiteDevil"]
a) Yes, if the ratio is the same and if your car has the same Coefficient of drag as the Falcon, and if your drive line is the same then you will be doing the exact same speed and same RPM, however, i would think that our Magnas are better in Co.Drag and because it's FWD, you should be doing that speed at just a slightly less RPM.


Ok, I don't get this.. what has Cd got to do with it? Cd is going to affect how fast he gets to that speed and indeed whether he can obtain that speed, but road speed is surely a direct result of how fast the wheels are turning (assuming there is no wheel spin). If your wheels have a circumference of 1m and are rotating 55 times per second you are moving at 55m/s.[/quote:9f9d87bcce]

okay, I understand where you're coming from, I guess I tried to put too many things into that one paragraph, what I meant by C.D was that it would reduce acceleration, but I didn't clearly state that in my previous post. you picked up on it,

Thanks.

maybe booya not so crazy dreaming of breaking land speed record in his magna.
top speed stock magna 3.0 = approx 215kmh at about 4'500 rpm,
redline in top gear = approx 250kmh at about 6000rpm,
engine capable of 9000 rpm = 50% increase= 375kmh
19in wheels throw gearing out by easily an extra 10kmh per 2000rpm, so add another 50 kmh to make 425kmh,
changing final drive from 3.5 to 3.2 ( just switching from a 3.0L to 3.5L stock final drive gear) would add about an extra 5 kmh per 1000rpm, so another 45kmh = 475kmh. could always go to 2.7 or 2.9 like a fairlane if thats not fast enough.
better check those wheelnuts and wear your 8) in case your windscreen implodes.
now when he gets past 300kmh his bodykit will fly off, the car will lose downforce and launch into orbit where the weightlessness will allow the rest of the top speed- hang on thats not a land speed record anymore..
will someone wake me up :lol: :lol: :lol:

First Orbital Magna Coming Right Up. How is the Smallest Jet Engine?

haha... this is funny.... i like booya's proposition... (i also like my diff theory, i've tested it plenty in GT3!!!, mind i did change all the gears so they were bloody close, just 1st was pretty long!)...

anyway... since all you engineers are fighting over how fast it will go, how about testing its speed on a dyno... then no drag is needed!!! dunno if dynos can go that fast, but hey, no drag!!

yeah, drag has little to do with speed related to rpm (unless its an auto box with no lock (or whatever they call it, can't think)

and as for the supercar argument, piss off!!! for top speed supercars suck!! there are plenty of cars that go faster than them (do a search for some salt lake speeds, i've seen a old square box doing over 300km/h!!!), the whole thing with supercars, is that they want them to handle well at that speed... the Veyron (?spelling) is having major problems with that at the moment, "they can't get it to handle at 400km/h" is roughly one quote i read!!!

Now, Booya, when you're finally doing 485km/h in GBM... don't turn a corner, hit a bump (or Roo for that matter :shock: ) , and pray!!!

dingo: call my comparison stupid but you just fortified my point. btw could be a bit more polite with your "piss off" howd ya like it if i turn around and tell you **** off for your comments? anyhow you just gave me a whole heap of other reasons why its rediculous. a street car cant travel at such a high speed even at a salt lake. Its too hard to make the car driveable at such a speed. Like you said.. multi million dollar development cant even get it right at 400km/h.. how the hells a 4 door sedan with nowhere close the aerodynamics and only thousands of dollars for development gonna manage 500km/h? btw do you see any of those cars that run on salt lakes run on the street at all? Dont think so.

Damn if anyone still thinks that 500km/h in a magna is reasonable go back to la la land

no-one has said a magna can do 500kmh- only that it is quite concievable for the wheels to be turned at rpm fast enough for that speed.
consider that neccesity is the mother of invention, ppl cant afford ferraris and lambos so they mod...
supercar outputs of 300 plus kw are now achievable for a lot of people, there are nissans, WRX's toyotas and V8's running 2 bar boost etc and dynoing between 500-700 kw. that kind of power also runs sub 10 sec 1/4 mile times when big enough tyres are on- that is faster than most supercars can achieve. if they building the drivelines tough enough to take that power under acceleration they can take it at top speed, and yes if the power and the gearing are there the wheels will turn fast enough.
ppl can buy wheels and tyres rated at 300 kmh plus.
ppl can buy fully adjustable suspension for springs, dampers and stabilisers- they can keep adjusting and go faster and faster and see what works best.
ppl can make fully adjustable front and rear wings and go faster and faster with continuing adjustments as they go.
and even a car with the engine in front can safely go over 300kmh now -thats demonstrated by the new Bentley continiental capable of 330 kmh. of course there is nowhere for amatuer people to develop aerodynamics and thats why no-one does it, if the dragstrip and dyno werent available ppl would not bother taking power and acceleration to the limits either.

Umm... it's one thing making the car's spin wheel fast enough for 500kph and getting the car propelled to 500kph. Going twice as fast takes 4 times the power or energy or something like that. You'll get to a point where the car just doesn't have the torque to push it.

And Wheels and Motor have only been as fast as 330. Their fastest driven cars were a Porsche and a modifed Skyline.

just you wait, booya will move onto using Turbine Engines soon.

Hahaha... speaking of turbines. I was at the GP and an F/A-18 flew past and the commetary team said they used turbofan engines and some kid said, "Cool, dad! A turbo powered plane!"

:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:

well, There's a Turbine bike, So i don't see why not a turbine car.

^_^

320km/h?

No Comments....

Booya,

Will send you an excel spreadsheet I did up that you can put wheel and tyre measurements into, and gear ratios, use it to your heart's content. Hopefully I can find your email on your website. Enjoy!

edit: sent to your wycliffe mail....
You wouldn't get a dyno to hold on at those speeds, Booya already jumped it, I think. MRT in sydney have a hub dyno that can hold more speed and power because you are not trying to hold the car down, it is just supported on its hubs without wheels. It's bolted on!

Engineers, please don't put us all down (I'm one too), just chuckle to yourself, and let him have a go.

Booya, please be careful and safe when you do get your car faster. I don't want to hear of any accidents. I also don't think that from your previous bodykit comments that I would be trusting it to keep you on the road at high speed. Just think that if your "flimsy" front bar dislodges at high speed while trying to give the front of your car some downforce (ie pulling itself off the bottom of your car), it has to go under the car, and that wouldn't be pretty at any sort of speed. As said before, just be careful, you have a family who loves you to think of.

dingo: call my comparison stupid but you just fortified my point. btw could be a bit more polite with your "piss off" howd ya like it if i turn around and tell you F*** off for your comments?
yeah sorry, it was meant more of a jovial "get lost" kinda thing... as supercars are not made for top speed, only to better the speed of their competitors while mantaining fantastic handling!

and seeing as you lot were obviously too lazy to go and google, i did it for you...

http://www.rbmotorsports.com/article1.html (fastest 4cyl @ 328km/h)
http://www.phoenixdiesel.com/records.html (big arse truck at 456km/h)
http://www.enjoythedrive.com/content/?id=30183 (pick-up at 247km/h)
http://www.ybenormal.com/ (worlds fastest production car 468km/h!, done in Y2K)

http://www.kugelkomponents.com/bonneville/bonneville.html ~ Even at 307 mph (491 km/h), the Firebird was showing absolutely no signs of getting light on the front."

and theres plenty more!!! go and google yourselves!!

as for booya's machine, go for it mate.... lets see a magna land speed record!!! (who cars if you cant turn a corner! and Lake Ayr isnt that far from you!!!)

APS fitted a Phase III kit to a stock XR6 turbo and clocked a top speed of 307kph, not bad for family sadan :D ,

Ohh and TJ exec, I don't thing anyone said the Magnas will do 400+ kph, it was a theoretical claim based on gear ratios and ideal conditions, not real world results, so chill, sit down and relax :)

APS fitted a Phase III kit to a stock XR6 turbo and clocked a top speed of 307kph, not bad for family sadan :D ,

Ohh and TJ exec, I don't thing anyone said the Magnas will do 400+ kph, it was a theoretical claim based on gear ratios and ideal conditions, not real world results, so chill, sit down and relax :)

Phonic, do you know ppl from APS? someone here works at APS.

phonic: yes booya said a magna can theoretically do 500km/h. 307 and 500km/h are a huge difference. you cant always listen to theoretical info because, hardly ever do ideal situations exist. It's like saying if you kick a footy at booyas head ignoring wind resistance from how far away could you kick the footy. <--- theres always gonna be wind resistance (unless you want to go into space)

dingo: i'd like to see that transam driving through your local neighbourhood. Hardly close to a production car let alone a street drivable car.

Nah just read up the info on their web site :D

[quote="tjexec] you cant always listen to theoretical info because, hardly ever do ideal situations exist.

Yes we all know that :? , I was trying to say that it was simply ment as an observation that "IF" so and so..., No one ever said it was remotlly possible in a real word environment. :)
Don't take it to siriouse :)

P.S taken from the APS site:

"From day one APS was committed to engineer a high quality 390 kW system which would continue to comply with the Australian design rule ADR 79/00 engine emission test, yet still be capable of running high 11 sec - low 12 sec quarter mile passes. In addition, to be user friendly and extremely drivable in every day bumper to bumper traffic."

Navigate the site below to see some interesting clips of APS Kitted Falcons :badgrin: :

http://www.airpowersystems.com.au/falcon/phase_iii.htm

phonic: yes booya said a magna can theoretically do 500km/h. 307 and 500km/h are a huge difference. you cant always listen to theoretical info because, hardly ever do ideal situations exist. It's like saying if you kick a footy at booyas head ignoring wind resistance from how far away could you kick the footy. <--- theres always gonna be wind resistance (unless you want to go into space)

yep, theory's a great thing, you know just over a century ago, we couldn't fly either, but someone had a theory that it was possible!! now we're on the moon, have the internet (who ever thought that was possible 100 years ago)... i agree, theory is only theory, but without it we'ld be still eating large shanks of meat, with a club in our hands, oh... and the world would be flat!!!

Oh and after many years of engineering at uni, I know that theory helps a lot of people to understand stuff... could you imagine if (and you being a mech eng should be able to understand) while in year 8 at high school they hit you with multivariable calculus, 2nd order differential equations, advanced kinematics, and full proof of newtons laws of physics!!!! me, at that age, was happy with s=ut+½at² etc and a² = b² + c², even though in practice it hardly even exists once you put in all the rest of the shit!!

[quote:26fbfca5bd]
dingo: i'd like to see that transam driving through your local neighbourhood. Hardly close to a production car let alone a street drivable car.[/quote:26fbfca5bd] yeah, me too! i'm sure it turns like a truck, but its still going that fast!

I'm really impressed Dingo. You, like, know stuff and everyfin'

What I'm most impressed about is how you did all those funky characters in your equations.

I nominate you to go look at the thread on Davies Craig EWPs in the Tech section and tell us if it's a hoax.

Oh, just realised you already have.

those trans am and firebird are exactly what i was talking about - about 700 kw-turbo engine with tall enough gearing, and adjusting suspension downforce balance continually to get to the speed. proves it is possible without jet thrust.
if u still need to see it in your street to believe it- watch out reversing out!

if u still need to see it in your street to believe it- watch out reversing out!
:lol: :lol: imagine that... cruising down the neighbourhood at those speeds!!! or even half them!!!!


and Reallyart... type in alt(hold) then 0 1 7 8.... voila ²!!!... ½ = alt-0189 (i use them a lot in reports for uni... heaps quicker than using insert-symbol-(find the damn symbol)-close insert box!!!!

oh, and most of the stuff i mentioned, i've forgotten how to do... i just know its there :? :? :? and its kind of a pain in the arse.... cause they more you know, the more you realise you don't know, and it just gets really confusing :? !!!

Hello to 89GSR,about that excel spreadsheet for wheel,tyre and gear ratios,for Booya.Any chance I could have a copy of that?. :D

its not healthy to re-live booya bashing topics lol

it depresses me... lol

PM me your email addy, and ill forward on the spreadsheet.

i say go for it booya! if you start hitting those sort of speeds you'll have to put the wing back on! :D :D :D :D and dont worry about tjexec, he summed himself up when he told us he is studying to become an engineer. ask any tradesman if you dont understand.

Hello to 89GSR,about that excel spreadsheet for wheel,tyre and gear ratios,for Booya.Any chance I could have a copy of that?. :DSent to the email you have listed in your profile.

Everyone seems pretty keen to bash booya for having a theory which was only related to possible rpm speeds. :confused: you don't have to be doing mechanical engineering to realise that the speeds he mentioned are not possible but i don't think that was the point he was making.

what he was really talking about was the possibility of increasing his top speed, sure it will take him longer to get there but that's his choice so go for it booya. but realise that your acceleration will be lessoned. there is nothing wrong with theory like it has been said where would we be without it. and doing one year of mechanical engineering doesn't make you an expert, hell i did first year engineering too, and and i've done two more after that specialising in mechanical and i'm still no expert. so i think we should give booya a chance, there is such a thing as a joke even if it is in the form of a hypothetical example :D

that was ages ago, but most ppl agreed with the theory and had some fun with it, not bashed it.

you could yes - but thats still gonna cost a fair bit of money isnt it??
Not really, get the specs for each gear and u should be able to have urself a ***** strong box for about 2-3grand. not even ur engine could break it i imagine.

you'll chew thru diffs tho.

What do you do for ur diff at the moment booya?

ps: your therory is theoreticaly correct afaik :P