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How slow is a 3.64?

Posted: Tue Aug 08, 2006 5:47 pm
by Quaser
Hi Guys

Just a quick question about lsd's - how much slower is a 3.64 compared to a 3.73 or 3.91?

im talking 0-60 and 0-100 times here.

would you really notice it?

Thanks

Q

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 5:53 pm
by Kos
on a 325i sport with a manual box you will be fine, it will allow you to hit 60 mph in 2nd gear

i prefered my tech 1's with a 3.64 compared to a 3.91 which i fitted

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:18 pm
by Quaser
2.7 convertible - currently has a 3.73 open diff on it

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:20 pm
by Kos
has it got a manual sport box ??

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:24 pm
by Quaser
yep

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:26 pm
by Kos
the 3.91 will be nice and buzzy, but you will be looking for 6th on the motorway at times!!!

i personally like a 3.64 holds it in gear for longer and it make use of the extra power and torque you have

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:32 pm
by Geoff
I had a 3.64 on my old H26. To behonest i would have wanted a 3.91 for better acceleration, but once your one the motorway is a demon cruiser. Saw the far side of 150mph on the clock at just about 6200, it rev'd to 6900 but couldnt really get it to go much faster.

My firends C2 has a 4.1 on, now that makes for quick acceleration. Still do 135 no probs.

I would have thought a 3.64 might be cheaper too?? Ask HartgeH27 or Iain for some prices. He may have one going.

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:43 pm
by Quaser
thats what im wondering - how much slower is a 3.64 compared to a 3.91?

I have a 3.64 diff at home - just wondering whether to fit it or not!

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:47 pm
by Kos
fit it, you wont regret it

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:50 pm
by Quaser
ok - which oil do i need to put in there?

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 6:53 pm
by Kos
dont know which one is recomonded , pm the oilman

i always use castrol

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 9:11 pm
by M5pilot
Kos,

Q has a very very heavy cabriolet. Even with it's quite powerful 2.7 it feels as though it needs shorter gearing. The car is only just quicker than a 325i sport due to the weight.

Cab's and tourings came with a shorter final drive from factory to make up for the extra weight they carry.

I've driven the car quite a bit already and it just doesn't want to pick up speed in 2nd. Already does just past 60 in 2nd indicated.

My personal opinion - go 3.91:1 and enjoy the acceleration! Who needs to go fast in a cab on the motorway anyway. It's noisy as hell @ anything over 80mph.

Geoff, your friends car has a 3.91:1 LSD - he cruises at 100mph doing roughly 4250rpm in 5th gear which equates to a 3.91:1 final drive.

Sal

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 9:55 pm
by stevetigger
Im happy with my 3.64 but I need to change it to LSD

And its noisy as hell over a ton! :mad: Car that is not Diff

I can cruise at 70@3300rpm

Re: How slow is a 3.64?

Posted: Tue Aug 08, 2006 11:05 pm
by Ziggy
Got to agree with Sal here - I prefer my cab with the 3.91 rather than the 3.64 (aside from the obvious due to it being an LSD!). & it's still fine on the motorway... didn't even notice any difference on economy; I fitted the cruise at the same time! :D

I'd get a 3.91 & sell the 3.64 - shouldn't be any difference in price...

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 8:43 am
by Geoff
Sal, Gareths car is (im told) an old press car and it came with a few different additions like the 4.1 as a mod?? Not sure but thats what Gareth says.

Oh F~@k it go 3.91 and tell all and sundry how quick it is! 8)

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 10:24 am
by MikeeMiracle
Quaser wrote:how much slower is a 3.64 compared to a 3.73 or 3.91?

im talking 0-60 and 0-100 times here.

would you really notice it?
Hell yeah you would notice it. I thought I was getting a 3.91 installed at the weekend for my iS but it turns out it was a 3.64 I have had fitted. The car came with a 4.1 open diff as standard. I recon im at least a good second slower to 60mph which im not happy about. Really wanna swap it for a 3.91 to get my acceleration back.

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 11:22 am
by Quaser
Steve - mine does 70mph @ 2750rpm???

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 12:03 pm
by Demlotcrew
Well i have gone through four diffs so far. (not because they broke)

3.46 > 3.33 > 3.25 and the last one is a 3.15 and each time i went up the car didnt seem to slow down at all if anything it got faster!

Andrew

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 12:24 pm
by M5pilot
I can definately say Demlots car goes like a bullet now, I can't see any 2.7 other than Player6's beating it.

However your S14 has a totally different powerband to an M20. M20's just get slow with long diffs. M3's can really use the taller gearing upto a certain point to their advantage.

3.91 Mr A1 Quas! You won't regret it.

Or wait until it gets it's final map done and then see how it goes. We know it's not putting down anywhere near as much power as it should right now.

Sal

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 12:28 pm
by Demlotcrew
Thanks sal!

I have got word of a New MAXX system coming out.

Ignition and fueling (plus a whole load of other features)

winkeye winkeye winkeye winkeye winkeye winkeye

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 1:32 pm
by stevetigger
Quaser wrote:Steve - mine does 70mph @ 2750rpm???
I have an M50 with direct 1.1 5th gear!

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 1:49 pm
by M5pilot
Demlotcrew wrote:Thanks sal!

I have got word of a New MAXX system coming out.

Ignition and fueling (plus a whole load of other features)

winkeye winkeye winkeye winkeye winkeye winkeye
They should make a 6Cyl version aswell.

Sal

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 2:22 pm
by Quaser
Dude - tell me more!!!

Sounds like an interesting comprimise!!!

Where can i get the clutch pack from?
Q

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 2:30 pm
by Ziggy
Andy, how difficult is it to swap a LSD unit (from an e30 diff) into another diff? Mine's got a whiney input shaft bearing... don't know if it'd be easier to just change that?!

Ta :thumb:

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 2:57 pm
by Demlotcrew
It really is not that easy to swap parts about from diff to diff!

Ziggy doing any bearing on a diff is really hard work! You need a good press, then a monster of a vice and a very large breaker bar!

You are looking at around £80 for parts.

Andrew

Re: How slow is a 3.64?

Posted: Wed Aug 09, 2006 3:01 pm
by Ziggy
Bugger. Guess I'll live with it for a bit longer, then cut my losses & stick the b****** on eBay. Thanks anyway!