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I pulled appart an R200 diff of my S12 for the first time. Now I am confused about the final drive gear ratio.
Everyone knows that it\'s 4,11 from what I understand. Mine seems to me 3,9.
I\'m not really sure about this so if there is someone who has a program or knows how to find out the ratio by counting the cogs could you telll me what the ratio is if the crown wheel has 39 cogs and the \"drive shaft input\" has 10.
It almost leans twords 3,9:1
you divide the number of teeth on the crown wheel by the number of teeth on the pinion.
you\'ll find most s12s will have a 3.9. it appears the 4.1 was an option in some versions.
Interesting....
All the info I\'ve seen says that the CA20E\'s and the CA18ET\'s were 4.11\'s, and the VG30E\'s are 3.9\'s. That\'s all US model stuff though. I guess it\'s highly possible that the Euro models all got the 3.9\'s...
Hmmm... I wonder if its worth further investigation? Maybe rip apart a diff (andother S12 duh) at a junkyard and see what that is... Maybe there is a much larger difference from the US and Euro spec S12 than what we had previously thought. Or maybe it was a MkII thing. Who knows.
I was verry sure all S12s had 4,11 final drive.
The FSM that I have is for the mk1 and it says the final drive is 3,9. Just thought of this as a typo or that the mk1 had a diffrent ration.
Now that I have actualy seen the diff I\'m surprised...verry surprised.
I have the crownwheel for a 3,5:1 final drive too. In what way would this be beneficial?
From what I can see on them the 3,5:1 is smaler then the 3,9:1. This should mean less tourqe but it should be able to spinn faster. So that should mean more top speed?
Theoretically yes. But you wouldn\'t know it unless you were pulled over. the thing is, the speedometer sensor that plugs into the tranny is specifically ment for the stock gears and tires. And the computer does the calculations and you see that translated onto your dash. If you change, lets say, bigger rims and tires, you WILL be going faster, but your speedometer will be off. Thats the downside (speedo needs to be corrected, and you lose bottom end grunt/ squirt coming out of the corners).
On the plus side: you gain some top end speed (not like the cars were really ment for top speed, more like corner carving) and since you engine will be spinning at a lower RPM at speed, you therefore save gas.
This is just everything I\'ve come to know over the years. If I\'m wrong please correct me.
Not to mension that you can\'t just change the \"crownwheel\". The ring and pinion is a gear set. You can\'t mix and match two different sets of the same ratio and expect them to live very long.
It is also not possable to use a different ratio ring (crown) than was originally installed. It would never spin as the teeth would just bind up, if you could even get them to slide together in the first place.
The 4.11 was in the FJ20.
The CA18ET got 3.9 in the auto\'s and 3.7 for the manuals.
what about the xe\'s? MKII? I would like a 4:11 final drive if at all possible in the long run.
The 4.11 was in the FJ20.
The CA18ET got 3.9 in the auto\'s and 3.7 for the manuals.
Look on the tag in the engine bay (on the fire wall), it should have the model of diff and the ratio\'s written on it. My live axle one is 3.7:1
Not to mension that you can\'t just change the \\\"crownwheel\\\". The ring and pinion is a gear set. You can\'t mix and match two different sets of the same ratio and expect them to live very long.
It is also not possable to use a different ratio ring (crown) than was originally installed. It would never spin as the teeth would just bind up, if you could even get them to slide together in the first place.
i know for a fact that my auto Aus-spec CA20 car has a H190 3.9 in it, and my other car (same, but amnual) has a 3.7 in it.
a 4.1 or 4.3 would be nice though.