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Ive been reading a bit about changing the final gear ratio in my gear box. J's racing use 4.3, MCR use 4.4 i was just wondering if anyones got any advice of what sort of ratio to select, if anyones completed a mod like this what sort of gains have u got, whats involved and how much??
Do some research on the Kia 4.56 gear. It is the preferred option for non-FI and available quite cheaply from Kia.
There are also a range of Mazda gears that fit.
yea the most important thing is ur gear ratios
i hope this doesnt sound too stupid, but are u saying to put a KIA gear in, as in KIA the korean or whatever car company??
No, I'm saying put the same gear in that Kia put in (the Sportage). None of these companies make there own gears. I realise it sounds bizarre, but that is the reality.
oh ok. Now to be honest if someone asked me to describe what a final gear is id have absolutly no idea, what is it exactlly??
I just re-read your post and what you are referring to and what J's and MCR make is a Final Drive Ratio for the diff. The Final Gear Ratio in the gearbox is different. It is a fairly complex piece. A company called ATS (I think) made one quite early on.
What I am refering to is the Final Drive Ratio which is the crown and pinion gear in the diff. OEM is 4:1. There are 4.3, 4.4, 4.56 and 4.77 options (and possibly more).
http://www.bulletproofautomotive.com...ail.php?ID=837
http://www.bulletproofautomotive.com...il.php?ID=4241
hey aus do u know if there's a page with the gears, the affects on top speed and RPM differences at different speeds, comparison? or anyone for that matter?
Somebody on S2ki did graphs for various gearsets with engine speed vs. road speed. That sounds like what you want. If I can find it on S2ki I'll link.
Here's a How to:
http://www.s2ki.com/forums/index.php...pic=85687&st=0
Top speeds (in MPH)
X 4.1 4.3 4.44 4.777
1 43.2 41.2 39.9 37.1
2 65.7 62.6 60.7 56.4
3 90.9 86.7 83.9 78.0
4 116.1 110.7 107.2 99.6
5 139.5 133.0 128.8 119.7
6 166.5 158.8 153.8 142.9
Here's the post about Kia gears.
http://www.s2ki.com/forums/index.php?showtopic=182172
thank you!
the car can only do 155 MPH right? but then with 4.44 u wont get to 100km/h in 2nd??? so 4.3 just gets u over 62mph...
ok so theres final diff gears and final box gears. That makes alot of articles i was reading make so much more sense.Anyway the reason im asking is beacuse i want to gain that acceleration advantage that the japanese tuners claim they have. so buying the Kia or Mazda gear for my diff, can i accomplish this? Is the diff casing still usable does it just slip in or is it a new unit all together? Sorry about all the questions im just really keen to know,uve been a huge help already. And just one more thing, what does changing a gear box's final gear do?
Oops no need to answer that, Aus ure a champ, ure links answerd all my questions. Its definitly the diff i wanna change. Praise be to all knowing Aus
My work is done! ;)
it's about time now to do my 4.7 final drive conversion!!!
but i really can't be bothered waiting, buying & finding each part seperately then pay labour to get it fitted.
does any one know if i can get all the parts and fitted in one shop? i really don't mind paying a bit more money to save all the hassle as i'm always busy que to long working hours..
and it seems like a big journing.
I've just sold my 4.57's to a local up here in Brisbane.
You will get raped if you go to a shop and want everything done by them.
Buy the parts required yourself, have everything ready then say, you want it all installed and cyro'd.
LMMF'nAO @ you will get raped!!!!!
people keep telling me when you make something stronger, everything else gets weaker... how does changing the diff gear effect the performance of the diff? has anyone installed one of these and then revved the **** off it!
Yes, for 2 years now with no problems.
well then, its settled. this mod is worth doing (and no, i am not being sarcastic)
you make everyone JEALOUS!!! you snicky devilQuote:
Originally Posted by WhiteAP1
If you want to know exactly what you're doing with gearing download Gearcalc from this site. http://www.locost7.info/gearcalc.php
Just enter your tyre size , diff ratio and S2000 6 speed (under tools ) and it will give you speed and revs in each gear in 10km increments.
An interesting piont that many miss when changing final drive gears in your diff is, due to the change in ratio, tail shaft speeds are more excessive and generally(not always) you'll get a light hum and/or vibration(not from driveshaft). So while your getting your gears done it's worth getting your tailshaft overhauled and balanced. Also changing final drive in gearbox is not a complex job at all, it's quite basic and theres less chance of ending up with a noisy gearset.
is cryo treated a must? what would you rate it out of 10 for importance?
It's not a must. As it's got it's pro's and con's. It is a good idea as it make the surface harder and less likely to burr on the ends of the teeth. Which in theory does make it slightly stronger, but it also does make the teeth more brittle, which can/is a down fall. It really come's down to one important aspect..... how you drive your car. Nothing will stop breakages if your hard or have an abusive style of driving eg. launches, burnouts, doughnuts, clutch kicking and worse of all, if you let it tramp. Cryo treating could actually have a negative effect under these conditions. Remember that the factory crown and pinions wheels are renouned for snapping.Quote:
Originally Posted by Simy
Are you hard on your car? or was the broken gearbox being unlucky.
lol.. i dont drive my car as hard as my mates.. they neva seem to break anything.. maybe its just the maintenence.. lol.. i think it was just unlucky.. i bought the car.. not in the best of condition, it had a history or blown diff and tail shaft... and i put the new clutch in.. n i think it was just time for it to go, couldn't hack the new clamp load...
Cryo treating doesn't make material more brittle. It just removes faults int he lattice structure and makes the material more evenly hard, not harder.Quote:
Originally Posted by JAP-S2K
Aus, your correct. My point, Cryo doesn't solve why they fail. Perhaps i should have explained myself a little more clearly. Doing Cryo treatment alone on the Crown and pinion wheels will have little, if any effect, as the cause the crown and pinion failure in our differentials goes way beyond the structural strength of the crown and pinion wheels (actual metal properties) themselves. Two keys area's seem to be the point where failure over time will occur. One being the diff collar (crush collar) and the other being the end caps which support the LSD centre. Both matters will result in excessive backlash, and overtime or through excessive abusive will cause failure to crown (more likely) and pinion (less likely) failure. Even then i know of a case where somebody managed to split a differential casing. If these area's are rectified to start with, perhaps we would see less failures. So what i'm trying to say is Cryo Treating may buy you time, much the same as spacers do for driveshafts. Your only fixing a known problem with a bandaid solution.
Maybe you should have said that instead of incorrectly stating that cryo treat makes the teeth more brittle.
My bad.
lol so angry guys.. lol cheers.. where could i get it done in sydney? pricing?
I don't get cranky! LOL
Pm sent.
any1 know which place in Perth can do the install?
JAP, what's the go with the differential collar thing? I'm thinking of getting it and then getting my diff's backlash set. Worth it?
Not that keen on doing final gear, but want to do pre-emptive work on the diff for piece of mind.
Any differential place with a decent reputation.Quote:
Originally Posted by MBLAQ
Workshops with a reputation for building drift cars should also know what they are doing.
That's just Aus, he aint being angry and neither is JAP. His answers might be short but they are too the point and usually correct.Quote:
Originally Posted by Simy
Yeah IMHO it's definately worth fitting a solid pinion collar if your current diff feels like it has plenty of backlash. It's not an expensive mod, seems totally pointless till you pull apart a diff and see just how much the factory crush collar can/is compress/ed, you realise why crown wheel failure is so common. I've seen quite a few apart now, each one with broken teeth had a rooted crush collar. If your plans are to keep it N/A and you don't have an abusive style of driving then this is all you'll need. However if your planning going down the route of F.I. then also upgrading the diff centre end caps to stronger, reinforced caps is also a sensible mod. As the extra torque will cause stress in these area's.
That's what I thought! Let me know when you get one, I'm thinking the J's one is good...we'll get a meal deal on the shipping lolQuote:
Originally Posted by JAP-S2K
Done deal. Pm sent.
I'm down for a diff collar too. Perhaps we can arrange a GB via PM?
JAP, you got PM ... :) thanks man