165 Kph In Third ,Help Diff Ratios

[evilkarlos]

can you suggest what diff ratios would be best?

I have a 700 kg car i made, with the 20 valve, t50, sprinter diff 17 inch wheels i am doing 165 in third gear.

Before i take the diff out to see what ratio the trd lsd is (the guy who supplied it forgot what ratio it was)what would be a good ratio?

I am now fitting a 4agze with rotrex super charger approx 250 to 300 hp.

[evilkarlos]

Does the lsd house the gears or is in the diff side so to speak?

[19914afc]

the crown wheel is bolted to the diff center (I.E your LSD) and the pinion (edit LRS) is bolted to say it simple to the diff housing, a 4.77 CW and pinion will have your speedo saying something about 160kmh when your only doing 110, very good for drifting, ect I think most people use 4.3 good all round still probably a bit high if you use the highway a lot.

Edited March 29, 2011 by LittleRedSpirit

[mungi mods]

diff ratio is dependant on rpm and overall wheel diameter . giving a speed without those is pointless

my old sprinter did 190km/h in 3rd gear at 7900 rpm with 235/45/17s with a 3.9 ratio s series.

 

what is the car going to be used for?

 

if you are increasing the horsepower i would probably stick with the current gearing , you don't want to go too short as you will waste the extra horsepower .

[evilkarlos]

The car will mostly be at track days hill climbs and the odd run in the hills.

Soon to be 4agze with rotrex

t50

sprinter diff

trd lsd

adj coilovers

gtr front brakes

std sprinter rear disc brakes

adj brake bias

silvia modified hubs with wishbone top arms

silvia adj castor rods

Hade made all aluminium body

I think it has a 4.1 so a 4.3 or above.

I might leave it as you said and wait till the motor is finnished.

Edited March 28, 2011 by evilkarlos

[ke70dave]

that is wicked!.

 

before you do anythign else you need to create a build thread for that! or at least post more pics.

 

what may help you out, is search around on the net (torrents..) for this spreadsheet that can help you calculate these things. there was a torrent around that was something like "TRD manuals" has heaps of good info. google "toyota TRD manuals torrent"...i think its the first one.

 

but there is a spreadsheet and you put in all your drivetrain details (tyres, gear ratios, diff ratios etc) and it will give you a graph of all the speeds in all the gears.

 

its quite easy to do the calcs yourself, but someone has already done all the work for you in this spreadsheet!

 

if you can't find it send me a PM with your email address and i can forward you the spreadsheet when i get home from work.

 

if you want to work out what is the "best" ratio, you need to decide how fast you want to go, then design your ratio so that you keep your engine in the torque band for as long as possible...i think.

[silverra23]

Norbie is your friend!

 

http://akb.norbie.net/Public/Gearing.aspx

[silverra23]

Oh and the main page

 

http://akb.norbie.net/Default.aspx

[evilkarlos]

Thanks Ill look in to it.

Some more pics for you.

[evilkarlos]

more pics

[LittleRedSpirit]

Looks terrific but I think you need to practice your glassing and get some compound curves into the body.

 

Should go like stink on poop.

[evilkarlos]

Oh and the main page

 

http://akb.norbie.net/Default.aspx

 

That is amasing i was out by 1.5 klms per hour.

Q. Why does the tyre width change the end speed?

[evilkarlos]

I own a sheetmetal shop so i stuck with what i know.

No fibre glass in it.

see attched how it would have looked with fibre glass or twice the work with alloy.

[LittleRedSpirit]

Oh hey I mean no disprespect, i think the nose would look awesome with some more sculpting, rear end looks awesome though, just a bit square on the front for my taste, but a terrific job done none the less, did you build it from scratch? Are those dirt bike dampers in the rear?

Edited March 29, 2011 by LittleRedSpirit

[pol090_ke11]

Hey evilkarlos are you in Tweed?