Bigger diff

[Johnmadd]

Did a lil research and I must find a rear diff from an automatic 330, it has 3.64 gears and the manuals have 3.07 or something like that. Less mpg's but more low end tourqe is worth it to me.

[danewilson77]

Really....so we're gonna take this on?

Droid! Srs Legitness!

[Johnmadd]

Wish I could get a lsd but this would make me happy. Higher diff equals more pull and ass felt HP.

[jvr826]

I have a 3.46 open in mine from a '99 autotragic 323. Best bang for the buck evah! I paid $200 shipped for it a couple years ago.

Also wish I could have gone LSD, but far too much coin. I wish there was a cheaper way to do that cuz it is a big improvement to getting the power down when exiting corners.

[ZSP-Mafia]

I did the 2.97 to 3.38 swap and the difference was substantial. Of course, I have a 5spd, so I'm doing 4000 rpm's at 80. But I don't do a lot of highway driving so it works for me.

[Johnmadd]

I have a 3.46 open in mine from a '99 autotragic 323. Best bang for the buck evah! I paid $200 shipped for it a couple years ago.

Also wish I could have gone LSD, but far too much coin. I wish there was a cheaper way to do that cuz it is a big improvement to getting the power down when exiting corners.

Exactly this, and off the line at the stoplights.



I did the 2.97 to 3.38 swap and the difference was substantial. Of course, I have a 5spd, so I'm doing 4000 rpm's at 80. But I don't do a lot of highway driving so it works for me.

I have a 4.10 lsd in my e30 and at 75mph im just above 3k on the tach.

[Gheybe]

Isn't the 3.64 from an automatic meaning its a 5 speed?

[kaboom]

I think a 3.46 might be a little tight for us, a 3.38 should be perfect! Or a 3.46 with a higher rev limit.

Ian

[bullfrogs_M3]

Don't just swap diffs. Find an M3 rear end and swap that ish! M3's are higher geared and LSD. Plush they almost completely line up and swap out. Your rear offsets will change but whatever.....

Here is what you need from an M3
http://i14.photobucket.com/albums/a335/wrecklessfool/CIMG6471.jpg

Some info from E46 fanatics
http://forum.e46fanatics.com/showthread.php?t=696388

Putting this in here because...well.....this is my summer project

[ZHP-FTW]

Did a lil research and I must find a rear diff from an automatic 330, it has 3.64 gears and the manuals have 3.07 or something like that. Less mpg's but more low end tourqe is worth it to me.

Do you mean 3.46 diff? Cause 3.64 is really high and I think is from the M3 only. I would recommend a 3.38 or 3.46 as those add a fairly aggressive bump in the low end. Personally I think a 3.64 would be too many rpms at cruising and require CONSTANT shifting. just my 2 cents.

[johnrando]

Do you mean 3.46 diff? Cause 3.64 is really high and I think is from the M3 only. I would recommend a 3.38 or 3.46 as those add a fairly aggressive bump in the low end. Personally I think a 3.64 would be too many rpms at cruising and require CONSTANT shifting. just my 2 cents.

My STEP has a 3.64 diff. John

[Johnmadd]

My STEP has a 3.64 diff. John

Thanks for confirmation John. Mileage would be affected for sure but the rpms should not be extremely hard on the engine as long as it well maintained, but that stoplight power and off and on ramp pull is what I like.

[ZHP-FTW]

My STEP has a 3.64 diff. John

Well I was referring to the OP's 6 spd manual. 3.64 for an auto/STEP is normal. 3.64 for a manual is a pretty big jump, but if that's what the OP is looking for, then that might be right up his alley.

[ELCID86]

Blast from the past. 3.38 Vs. 3.46...

[stephenkirsh]

Just so everybody here is clear, the no -zhp autos are 3.46.

The zhp auto is 3.64.

If you want a 3.64, you'll need to source it from an auto zhp, which I believe there's only about 7500 of those in the US.

I think a Z4 might share the same diff, too. Unsure of auto or manual.

[Damian]

I swapped in a 3.38 from my prior e46 (non-zhp auto). Butt dyno says it was a good swap. LSD just isn't worth it for me as this is my DD

Sent from my XT1585 using Tapatalk

[derbo]

Just so everybody here is clear, the no -zhp autos are 3.46.

The zhp auto is 3.64.

If you want a 3.64, you'll need to source it from an auto zhp, which I believe there's only about 7500 of those in the US.

I think a Z4 might share the same diff, too. Unsure of auto or manual.

3.64 is available from a Z4 3.0si auto
3.46 is available from non330i auto.

Here is a long list:
http://www.bokchoys.com/differential/GearRatios.htm


Remember majority of the time, the flanges will need to be swapped with your existing diff.


From my old emails with Performance gearing:

Coming from a 3.07 stock final drive:

3.46 is a 12% increase in acceleration
3.64 is a 18% increase in acceleration

0-60 times will be reduced due to an upshift to 3rd. :)

[wertyu78]

I've been daily driving a 3.64 LSD (non-m diff) for over two years now. I drive 20k + miles a year. Besides it turning high rpms on the highway (3-4k), it's just fine. I still average 23 mpg combined, and see 28 on the highway if I don't drive like an arse.

TLDR: Take it from someone who has been running the 3.64, you'll be just fine. If you don't want to turn the RPM's, 3.38/3.46

[slater]

Coming from a 3.07 stock final drive:

3.46 is a 12% increase in acceleration
3.64 is a 18% increase in acceleration

0-60 times will be reduced due to an upshift to 3rd. :)

yeah, but 0-60 doesn't matter - the 12-18% increase is noticeable everywhere. :)

i have a 3.46 (w/ helical LSD) and i love it. every gear is better (except 6th ;) i would love a taller 6th!)



I've been daily driving a 3.64 LSD (non-m diff) for over two years now. I drive 20k + miles a year. Besides it turning high rpms on the highway (3-4k), it's just fine. I still average 23 mpg combined, and see 28 on the highway if I don't drive like an arse.

TLDR: Take it from someone who has been running the 3.64, you'll be just fine. If you don't want to turn the RPM's, 3.38/3.46

even my 3.46 is 2950rpm @ 75mph (stock was 2600rpm). it's a noticeable difference, even though it doesn't sound like much on paper.

i was averaging 32mpg on the highway with the stock 3.07 ratio, now i'm averaging 30mpg with the 3.46 - however, it IS winter and fuel economy always goes down when the temps are cold. curious to see what i get in the summer.

[derbo]

I've been daily driving a 3.64 LSD (non-m diff) for over two years now. I drive 20k + miles a year. Besides it turning high rpms on the highway (3-4k), it's just fine. I still average 23 mpg combined, and see 28 on the highway if I don't drive like an arse.

TLDR: Take it from someone who has been running the 3.64, you'll be just fine. If you don't want to turn the RPM's, 3.38/3.46


yeah, but 0-60 doesn't matter - the 12-18% increase is noticeable everywhere. :)

i have a 3.46 (w/ helical LSD) and i love it. every gear is better (except 6th ;) i would love a taller 6th!)




even my 3.46 is 2950rpm @ 75mph (stock was 2600rpm). it's a noticeable difference, even though it doesn't sound like much on paper.

i was averaging 32mpg on the highway with the stock 3.07 ratio, now i'm averaging 30mpg with the 3.46 - however, it IS winter and fuel economy always goes down when the temps are cold. curious to see what i get in the summer.


on my 3.62 LSD (M3 Diff) , 70MPH is about 3000rpm. I average around 28mpg on the freeway if I drive like a nanny. I don't daily drive it, so I get somewhere more like 24-26mpg on the freeway.


IMO, a great daily driver ratio is a 3.46. I would prefer it over the 3.38. The 3.62/64 is a fantastic ratio for driving around town if you love shifting (which I do.)

[ELCID86]

Loving my 3.38 Helical. Do wish 1st and 6th were a bit longer. But love it just the same.


---
"ZHP is a garbage option anyway- just some cosmetic upgrades with a different cam and diff to claw back some of the performance lost fitting those hideous and heavy wheels. Any 330 with a 3.46 diff will smoke a ZHP every time. The whole Mafia thing reeks of childish behavior." - an e46fanatic