4th gear

kyro_02 · 14-06-2006, 07:00 PM

anyone know the 4th gear ratio for a 4 speed auto ... ed fairmont

cheers

Sweet_EL_ · 14-06-2006, 07:04 PM

don't you have your owner booklet thing?? coz it had the rarios in there???

needfordspeed · 14-06-2006, 07:10 PM

0.68 .....

OED666 · 14-06-2006, 07:13 PM

Quote:

Originally Posted by needfordspeed

0.68 .....

correct sir!!!!

kyro_02 · 14-06-2006, 07:13 PM

ta... yeah i got the booklet somewhere but it's under a lot of stuff!!

ta needforspeed!!

when i get 4.11's i wanna get it changed so i get fast take off but at 100km/h it will be about 1800/2100 rpm once its changed .. or whatever is closer to stock revs ??

mcflux · 14-06-2006, 09:42 PM

Huh? 1800-2000rpms at 100kph with 4.11s? Dreaming.

Try somewhere around 2300-2400rpm with the six (it's 2250rpm with the eight)

These autos are short-diff-gear-friendly though, it's not like the old days where a 3 speed auto or a 4 speed manual + 4.11s meant 3500rpm and 200km fuel tank range lol

OED666 · 14-06-2006, 10:15 PM

i dont know what options are available for changing the 4th gear ratio in the auto, and what implications it would have with the computer

Damo · 14-06-2006, 10:20 PM

get 3.7's my car sits on 2000 rpm at 100 kmh. Perfect compromise.

kyro_02 · 15-06-2006, 10:48 AM

Quote:

Originally Posted by Ghia5L

Huh? 1800-2000rpms at 100kph with 4.11s? Dreaming.

what i mean was, 4.11 diff gears.. and get the 4th gear in the auto changed to suit 100/110km/h at 2000/2200rpm or whatever... i am going to speak with the mechanic about it etc.. but there is probably going to be something stopping it like the ecu but hope not... i will be doing a lot of freew/highw travel and i should be going to qld latish this year so i want it to be good on fuel as well

Aaron_EF8 · 15-06-2006, 11:48 AM

There's no-one making different ratio's for BTR's. I've heard rumours that there will soon be a 3.00 1st gear, but I really doubt anyone will make a 4th gear replacement.

T5's have a different top gear ratio to BTR's as well.

sam12h · 15-06-2006, 12:03 PM

You want acceleration & economy?

Then you should put a T5 in it & use 3.27 or 3.45 gears. Acceleration when you want it, economy when you keep your right foot out of it.

2nd gear in a T5 & 1st on the btr are almost the same, so launching the T5 in 1st (be it the EA's 3.5:1 or the later E-series 3.25:1 or 2.95:1) will get you off the line smartly, with any diff ratio from 3.27 up to 4.11. Manuals also transfer more fwkw into rwkw.

The other side is manuals use less fuel (when driving normally). When i swapped from the BTR to the T5 in my EB GL 5.0L, the highway consumption of LPG went from 17-18L/100km down to 14-15L/100km, despite 5th in the T5 being shorter than 4th in the BTR.

Think about it. :eclipsee_

Walkinshaw · 15-06-2006, 12:26 PM

Quote:

Originally Posted by kyro_02

what i mean was, 4.11 diff gears.. and get the 4th gear in the auto changed to suit 100/110km/h at 2000/2200rpm or whatever...

No deal. No replacement 4th gears in 0.62/0.58 etc like there are in T5's.

You are stuck with 2.39, 1.45, 1, 0.68.

kyro_02 · 15-06-2006, 01:13 PM

yeah i just rang up and he is you can't change 'em cause they have already got overdrive or something along those lines... and said i should try 3.91 or 3.45's diff gears(he said new 3.91's rev about 2500 rpm?)

getting new 3.91's and a full spool $1000 anyone think that is cheap or expensive?

cheers

OED666 · 15-06-2006, 02:06 PM

expensive!!! new 3.9's shouldnt cost anymore than $550 fitted, and you can get a mini spool for $70 off ebay...

why are you going a full spool??? wouldnt a mini spool be just as effective???

kyro_02 · 15-06-2006, 02:09 PM

yer i don't trust ebay,,, is there a shop that sells spools otherwise i got no choice but to get it from the mechanic :P

i will sus the 3.91's side of things soon and maybe ring up a different joints but the first joint was $1400 for the same thing lol.. i was nuuup and then i rang the joint who did my bro's diff and it was $1000 which was cheaper

delta · 15-06-2006, 02:09 PM

It would be possible to change the overdrive gear ratio with a complete new gear set (sun, ring, planetaries) but because of the way an automatic transmissions gears work you would also be changing every other gear ratio in the box.

This http://auto.howstuffworks.com/automa...nsmission3.htm describes it much better than i ever could.

As far as I'm aware nobody makes a complete replacement gear set for our boxes yet. I'm sure as more and more XR6T's take on the quarter and start breaking boxes that someone will step up to the plate with a nice new heavy duty gear set.

sam12h · 15-06-2006, 02:25 PM

Quote:

Originally Posted by kyro_02

yeah i just rang up and he is you can't change 'em cause they have already got overdrive or something along those lines... and said i should try 3.91 or 3.45's diff gears(he said new 3.91's rev about 2500 rpm?)

getting new 3.91's and a full spool $1000 anyone think that is cheap or expensive?

cheers

I give up. You seem to have more $$$ than sense. Spools (full or mini) are illegal & will void your insurance. T5 & 3.45 (with or without lsd) will wipe its bum with anything an auto & any ratio can do with the same mild 4.0L or 5.0L in front of it, using less fuel & still be LEGAL.

Keep the auto if you really want to, but keep the car legal too. Get a 3.89 4pin 28 spline & lsd centre from an R31 skyline & you wont void you insurance.

Excuse me while i unsubscribe from this thread.

kyro_02 · 15-06-2006, 02:33 PM

Quote:

Originally Posted by sam12h

I give up. You seem to have more $$$ than sense. Spools (full or mini) are illegal & will void your insurance. T5 & 3.45 will wipe its bum with anything an auto & any ratio can do with the same mild 4.0L or 5.0L in front of it, using less fuel & still be LEGAL.

Keep the auto if you really want to, but keep the car legal too. Get the 3.89 4pin 28 spline centre from an R31 skyline & you wont void you insurance.

Excuse me while i unsubscribe from this thread.

sorry you can't accept the way I want to go, not sure what else you could accept if this really affects your life.

1.) I know mini or full spools are illegal "LOL its goin on my hotted up drag car omgz" there's my defense... so it's only illegal on the street :P

2.) I know a manual could kick auto's butt, but the thing is I hate manual specially when you have to change it in slow traffic... gets annoying, but because these gears and spool will be going in a "DRAG CAR!!!" it wouldn't be on the road :P :P :P

i think you're coming down to thinking i should get a manual, but lets keep it legal won't we? i won't be able to drive a manual if i have an auto license... unless i do a test with instructors in a manual car... so because i have an auto and i don't plan on getting a manual car any time within 3 years then there isn't a point :P

EFFalcon · 15-06-2006, 02:39 PM

my car was about 1750 - 1800rpm @ 100 with a 3.08, about 2000rpm with 3.45, so you'd be lookin at about 2250-2300rpm for 3.9's

kyro_02 · 15-06-2006, 02:41 PM

yeah should be all good anything under 2500 rpm with 3.91's and i'll be happy

mcflux · 15-06-2006, 05:19 PM

Aaron: 3.0:1 1st gear? Orthm! I'd love to know more

:

kyro_02: listen to OED666... So you're saying you're happy to pay $1000 for a spooled 3.91 diff, but paying $550+70 by sourcing an ebay spool instead is a no go?

The $380 change you're looking at could get you around 8 pairs of burnout tyres for your sik spooled 3.91 diff... Or replacement suspension parts instead when they prematurely wear out... Or rear brakes...

kyro_02 · 15-06-2006, 06:19 PM

i don't understand how i would be paying $550 + $70 fitted ... with 3.91's and a spool... and saving $380 when the guy said $1000 drive in drive away he supply's parts? (what mechanic did OED666 go too to get his gears fitted or did he do it himself?)

i've rang up a few places and they have only been telling me prices $1000 and over for new 3.91's and a full spool (i want a full spool cause it's the whole centre and i believe will last longer.. i don't mind paying the extra $60 odd extra off ebay for a full spool. mini spool is like $80 off ebay.

EB Pete · 15-06-2006, 06:44 PM

i don't really understand all this mini spool crap but i got quoted $1000 at the most for 3.7s LSD set up in my car. is that anygood? is there a thread that has covered all the diff options and what they all mean?

kyro_02 · 15-06-2006, 06:58 PM

minispool and full spool do the same job, they both lock your axels so they rotate at the same time without delay, better then an lsd(spools last longer then lsd's) but your axels could snap .. thats when you buy billet axels and you shouldn't ever have a problem :P except gearbox and/or engine dying a terrible death andspools can lead to long term tyre wear and chirping off the wheels.... etc. full spool being the stronger one I believe... and it should be cause for an extra $60 ish!!!

I too go quoted $1000 but for 3.9s and a full spool(but i will supply full spool so its cheaper) so unless anyone knows of a mechanic who can do a better deal then I got, no choice but to got with him ...

EB Pete · 15-06-2006, 07:01 PM

why would you want a mini or full spool? what advantages does it have over an LSD?

kyro_02 · 15-06-2006, 07:08 PM

there is advantages and downsides...

advantages: you will have way better control in a a drift or just flicking the rear as to a LSD... if the LSD starts spinning 1 wheel then it's got loose.. and if/when it starts spinning one wheel whilst going sideways you could very well lose control...

disadvantages: if an axel snaps((thats why you buy billet axels :P)) during a skid your could lose control.... slow turns(unless you change your driving habits you can master it as normal as a person without a spool, though bigger turning circles, wheels chirp, long term tyre wear if you do not to burnouts(chirping wears rear tyres), short term if you do burnouts... also it's illegal on street cars...

the above is what i've been told by people with spools

OED666 · 15-06-2006, 07:15 PM

another disadvantage is the excessive wear on trailing arm bushes. they wont last more than 4 weeks.

i had my diff gears fitted by mal wood automotive. i didnt have to find gears, they have everything.

$1000 is a good price for new gears, and a re-co'd lsd centre.

EB Pete · 15-06-2006, 07:26 PM

well i'l just stick with the lsd as i'm used to drifting with an open diff.

OED666 · 15-06-2006, 07:33 PM

i am getting a thrash diff, 3.08 mini-spooled (from ebay)

http://cgi.ebay.com.au/9-inch-Diff-F...QQcmdZViewItem

kyro_02 · 15-06-2006, 07:40 PM

interesting, same guy i will be dealing with if i buy a full spool from ebay, hopefully i don't get screwed about

may i ask, do you mean thrash diff as in something to cain and when it s itself put your good diff back in?