Toyota G series Diff question

[cossie55]

Guys,
I am racing a car, and have a G series toyota diff in the car. Now I need to find the longest ratio available (3.0:1 or alike). I need only the crownwheel and pinion.

Anyhow, can anyone tell me what cars had a G series diff in them, and what ratios?

Let me start
Hilux - Ratios 3.5, 3.7, 4.1, 4.8, 5.1


Other cars I have had suggested to me that have a G series (8") crownwheel setup:
Supra (some models)
Century (cant seem to confirm ratios)
Lexus (not sure which model)

I have already had a diff centre pulled out of a Century in Japan, only to find that it had a 3.7:1 in it, but I wonder if that is just that car or model....

Any help that you can be would be appreciated.

regards

Jamie

[andrew_mx83]

cressida (3.9)
landcruiser
soarer?

[hypo23]

theres a couple of stores on ebay selling these at different ratios, cant remember what they go down too though.

[2jzhilux]

Search for motive gears on eBay they come in a few different ratios

[cossie55]

Tried Motive Gears,
Tried Richmond gears
Tried Yukon gears

3.50 is the lowest I can find...

But I keep reading people saying that this or that one fits...

Basically the most reasonable lead that I have is that the Toyota Century, and the toyota Supra both have a G series diff, and that there was a 3.0:1 (or thereabouts) ratio available in one or both of these models...

hoping an expert out there can confirm or deny this absolutely..

thanks again

Jamie

[roadkill]

Hi Jamie,

according to this toyota diff code database

http://www.toysport.com/technical%20...ifications.htm

there was no factory ratio lower than 3.30

Then there's this one here

http://www.toymods.org.au/forums/showthread.php?t=350

that says there is one that there are a few under the 3.09 mark. Downside to these tables is they don't say what combinations there are, just what each of the parts of the code translates to. If u want a g series with a 3.0 ratio the code you'd want would probably be G71x (x referring to pinions and limit slip) if it even exists

Good luck finding that!

bEn

[cossie55]

Thanks very much for that reply. I have seen those as well, but no real confirmation on which car, if any actually had that combination. I am hoping that one of the guys here on the Forum may be able to confirm definitely what diff ratio is in the Century, as it seems like the most likely car to have a low diff ratio in it.

Otherwise, it is time to sell my gearbox and get another one, which will be a bit of a problem!

thanks again.

Jamie

[roadkill]

hI,

I must ask why are you searching for such a low ratio? Is it top end speed? When engine/box etc are you running? Given how rare the century is i wouldn't bother trying to hunt it down even if it did come out with one somewhere along the line. I think you'd be better off looking for a new set on ebay? I've seen people offer different ratios for g series (just look for hilux diffs) NEW. Surely that's gotta be easier and cheaper than stuffing about finding a different gearbox?

As foor for thought my hj monaro had a 2.7 or 2.9:1 diff. Maybe that's a better way to go - look for something you know has the right ratio and get that diff to fit?

bEn

[cossie55]

My top speed needs to be about 260km/h for Bathurst to be competitive. With a 3.5:1, I am limited to about 230km/h at 7500 rpm.

The car was already doing 235 @ 6600rpm in 5th gear at phillip island on its first outing as you can see in the picture. That was with a standard overdriven gearbox.

If I go back to a 1:1 top box, I will be totally screwed at Bathurst.

The gearbox is a specially made racing box, with a 1.0 : 1 5th gear. That is why changing the box isnt really an option.

The diff has also already cost quite a bit to turn into a fully floating cambered diff, so changing away from a G series diff isnt really an option either..

quite a problem really!

thanks again.

[roadkill]

Hi,

so excuse my ignorace....

Why go to a different box if the old one was where you wanted it to be? I'm guessing there may be a strength issue but that'd be about it

What car, what engine etc r u running?

bEn

[cossie55]

Sorry, should have spelt it all out up front..

Datsun 1200 coupe - SR20DET IPRA race car. Hilux G series cambered diff in the rear.

the current gearbox is a stock overdriven SR20DET gearbox out of a silvia. Broke 5th gear in it on the weekend at Winton.

I have an Albins dog box to go in the car that I cant use until I find this ratio.

I am getting close to giving up, but thought Id have one more go to find this diff ratio. I will just have to sell the dog box without it, as I cant use it with what I have.

Was hoping for a little expertise on G Series diffs from a Toyota forum...

thanks.

[roadkill]

Hi,

problem is you may be searching for something that doesn't exist! You can buy the G series crownwheel and pinion on ebay of various sizes but from 3.54 is the smallest i've seen. Worst case you could get one custom made maybe?

Try the supra forums too as they (all) had g series in them so they should know alot about them. I'd say look at the 4b ones aswell bu they to look for the opposite end ratios!

The problem is i don't think that there is an actual list of all the diffs offered throughout the toyota range.

bEn

[72rona]

I have a "G" series rear with really tall gears either 3.09 or 2 something, I forget the exact ratio. I have it in storage and won't be able to get to it till December. But it has a special third that has a huge pinion and about a 4" mounting stud on 1 of the studs. I got it off a '94 Toyota 2 wheel drive 1 ton pick-up truck a U.S. version it had a 22re with automatic in it. I'm not sure if you have this similar truck over there but I pulled a lot of toyota third members at the junkyard here and this was the first and only one I seen like it. I can get exact specs and pics but like I said It wont be till December.

[WDE_BDY]

Century runs a G392, or at least this one does -

Good luck finding one though.

Callum

[RT40Corona4AGTE]

go to this ebay ad

http://cgi.ebay.com/ebaymotors/TOYOT...Q5fAccessories

visit the sellers store first, and it appears he makes his own diff gears

contact seller, get ratio you want made up

race and blow your wad! its that simple