Please explain the differences in the G50 box

[V8Dom]

hi

if you email me i will send you a program ive been working on which shows the boxes available to us and when you input revs and the gear number it tells you automatically what speed you are doing....its simple and very easy to use as its in excel format...

its nearly finished but all the 5 speed boxes are in there... im just finishing off the 4 speed(need gear ratios please) and the 6 speed boxes just sorting formulars... it even allows you to change your tyre diameter and you can see the difference it effects the speed of the car and the final gear ratios you can see the difference in speed in each gear.

ive converted it as time is on my side at the moment and everyone keeps asking the same question on each build... Hopefully this will solve all your problems

Dom

[spatz]

I have no problems but I can put your excel file on my server and make it available here in this sticky if that is ok for you ?

[V8Dom]

spatz said:

I have no problems but I can put your excel file on my server and make it available here in this sticky if that is ok for you ?

hi If you pm me your email address and ill send it over to you to have a play with... I need the 4 speed gear ratios to finish it..

Dom

[spatz]

here you can find the info you need

http://www.californiamotorsports.net/930.htm

regards

[V8Dom]

thanks ...Ill polish it off this weekend and email it to you when you've PM;d me your address for you to have a look at..

I did this for everyone here in the ultima forum to enjoy, but i hold the copy rights so no selling it .. if you want other gearboxes adding just ask and ill modify it as time goes by...

Dom

[LuckyP]

G5003 7000 RPM How close to 176mph does your programme get?

[V8Dom]

LuckyP said:

G5003 7000 RPM How close to 176mph does your programme get?

hi 178mph but that is with a tyre diameter of 25.5 inches.... ive only estimated that as i cant measure mine due to my leg...

25 is 174mph
25.25 is 176mph
25.50 is 178mph

Pete emailed you a copy.. still modiying it with axle diff ratios.. let me know what you think???

dom

[LuckyP]

It's very good Dom. Just wish I had that at the start of the build!!

Very easy to use, nice one.

Pete

[V8Dom]

LuckyP said:

Just wish I had that at the start of the build!!

Very easy to use, nice one.

Pete

Thanks Pete..I hope it will help everyone here in their hunt for the ideal ratios... you can even change the gear ratios in each box and see how it effects speed.

(by the way if you had had brand new tyres on the car (not Kumo) your tyre diamener according to the internet would have been 25.91 inches and 7k would have been 181mph....but that would depend on tyre pressure and how much the tyre would bulge..... so this is a rough idea program but fairly accurate..

Dom

Edited by V8Dom on Friday 26th February 17:18

[Storer]

I wonder how much tyre deformation (bulge) affects the speed.

The radius is reduced but the circumference of the tyre must remain the same so for every revolution of the wheel the car travels the same distance does it not? Have I got this right or should I just keep quiet and not show my ignorance.

Paul

[V8Dom]

Ok guy my program is finished....

I hope it helps all of you deciding about gear ratios..I never used it as my box came with the car..

Spatz can i have your email please to shortcut it off your site.

Anyone want this on their desctop, PM me and Ill send it to you..

If anyone finds a fault in it let me know as we are not all perfect..

when choosing a gearbox, 4, 5 or 6 speed make sure your final drive ratio is correct in the box... You will also find depending on tyre manufacturer your tyre diameter maybe different..again you can adjust that as well..

All the ratios listed you can adjust and speed will adjust accordingly... so if you fancy a standard G50/03 with a higher top gear, adjust the top gear ratio on that box....again if you fancy a standard box and want to change the final drive ratio, just change it.




Dom

Edited by V8Dom on Saturday 27th February 20:58

[spatz]

I have added DOM's excel file in an earlier post, so people do not have to read all of our BS before they get to the vital infos, many thanks Dominique !

[YIIHAA]

I have a slightly different version of this that allows you to select a gearbox and rev limit, then calculates rev limited speed in each gear and revs for each speed and gear. My table includes the GTM factory five gearbox and ZFQ as well as a few gearboxes that don't seem to be listed on Dom's spreadsheet. Happy to send it to anyone via PM, but don't have anywhere I can host it to link to.

[V8Dom]

YIIHAA said:

I have a slightly different version of this that allows you to select a gearbox and rev limit, then calculates rev limited speed in each gear and revs for each speed and gear. My table includes the GTM factory five gearbox and ZFQ as well as a few gearboxes that don't seem to be listed on Dom's spreadsheet. Happy to send it to anyone via PM, but don't have anywhere I can host it to link to.

i can add your gearboxes if you want or just change some of the redundant ones on there and save it....

The info is for everyones ref as ive already got my perfect box.... i was just bored and alot of guys were asking!!!!!!! what did you think of the program??? helpfull??

Dom

[spatz]

send me the file to my email adress and I will host it on my server

[Storer]

Dom

Usefull spreadsheet, thanks.

It confirms my calculations for my now purchased G50 20 gearbox to within 1 mph in top so I'm not as dumb as I sometimes feel (and probably look).

Paul

[V8Dom]

Glad it helped...

To me that is what the forum is all about, helping others and getting to know fellow ultima people..

I found it interesting the changes tyre diameter make ... 8mm new tread against 2mm worn tyres was a 1/2 inch difference and 5mph at the top end...5mph is 5 mph.. Id like to know if tyre growth happens at that speed as well or tyre squat (bulg in the tyre) but only as a matter of interest rather than being dull...

1mph factor??? you did well ... you know as the tyre measurement will make the difference, there could be your 1mph.

Dom

[spatz]

i can imagine that tyre diameter will grow at higher speeds especially in the middle of the tire, not much but maybe worth considering, depending on how much downforce is to reverse the effect. For me the top speed is a matter of balls not engine power or gear ratios...I think I have enough of both...

[spatz]

ok we have now two very nice XLS sheets thanks to Dominique and Paul,
I figure I need my LS7 rev up to 6800 and then I am flying the 200mph, so if I cannot reach the revs, I know I am not there.......

Edited by spatz on Wednesday 3rd March 14:18

[UltimaCH]

V8Dom said:

Glad it helped...

To me that is what the forum is all about, helping others and getting to know fellow ultima people..

I found it interesting the changes tyre diameter make ... 8mm new tread against 2mm worn tyres was a 1/2 inch difference and 5mph at the top end...5mph is 5 mph.. Id like to know if tyre growth happens at that speed as well or tyre squat (bulg in the tyre) but only as a matter of interest rather than being dull...

1mph factor??? you did well ... you know as the tyre measurement will make the difference, there could be your 1mph.

Dom

Centrifugal force being what it is, I imagine that at high wheel rotation, the tyre will expand outwards making a bigger overall circumference. Look what happens when a dragster spins the wheels to get some heat in the tyre. It expands like crazy, but then the side walls are also taller than our sports and low profile tyres.