The semi-Comprehensive M60b40 into E30 swap Q&A

[bmwmech1]

I know, I was more being facetious than anything, but the math makes it pretty plain, doesn't it?

Garey

[The Dark Side of Will]

The Getrag 260 has 3.82 first and an E30 has... 3.73 gears? (not sure... I know the iX manual cars have 3.91's) for an overall of 14.24.
With 160 ftlbs at the engine, that means 2280 ftlbs at the axle for a stock car.

The ZF has a 4.20 first. With a 2.93 rear for 12.3 overall.
With 300 ftlbs, that's 3690 ftlbs at the axle.
With the 2.54 second and 2.93 axle, 300 ftlbs at the engine gets you 2230 ftlbs at the axle.

IOW, the M60/ZF car will pull as hard in 2nd as the M20/260 car does in first.
I don't think the E30 body has a prayer of hooking up an M60 in first gear on street tires.

[bmwmech1]

I think with 2.93, you'll never have any traction in first, and maybe not in 2nd either.

I hope that's not the case, or else I'll have to find a 2.56 rear end... no way I'm looking for a tire shredder in 1st and 2nd...ugh...

Garey

[The Dark Side of Will]

A 4.0 could *EASILY* pull a 2.56 rear end with the 5 speed.

I think with 2.93, you'll never have any traction in first, and maybe not in 2nd either.

[CoreyZ]

Reposted:

http://www.turnzero.com/technical_resources.php?resource=gear_calculator

A 2.93 puts you at a 157.5 mph top speed in 5th with a ZF 310, assuming a 6500 rpm redline and 225/50/15s on there.

That'll put you at about 3k at 70mph.

A 3.15 gives you a 146.5 mph top speed, and jumps your cruising rpm ~200.

Using a 420G Getrag with its 0.83 6th gives you 2600rpm at 70mph, and 176.5 mph top speed with a 3.15

Pretty fun to mess with.

1------2------3-----4-----5------6---- R
4.32 - 2.54 - 1.62 - 1.23 - 1.00 - 0.83 - 3.75

^ Getrag 6 speed ratios. The ZF 5 speed ratios should be identical, just without the 6th gear.

I've posted here before as Mr Two, name change came about when our shop started sponsorship. Hopefully I'll start gathering parts in the next few months :)

[mkcman17]

sweet! flywheel ordered. now it's REALLY decision time on the trans.

[JGood]

JGood, sign me up for one please. i'm tired of kicking around looking for one.

PM Sent.

Autopartswarehouse has the Sachs Sport clutch on clearance for $231 shipped, with discount code APW2012, it comes out to $208 shipped. Not sure if it will hold the power, but as I said earlier, guys run 300whp turbo setups on stock m52 clutches. I'll report back as soon as my car is running, but that won't be for a few months.

[mkcman17]

JGood, sign me up for one please. i'm tired of kicking around looking for one.

[Jean]

Oh, used! gotcha :) Yeah, those guys are local and I have purchased a few things there, but sometimes they ask WAY TOO MUCH for basic things there like it's made out of gold :/

They quoted me like $500 for a harness, $1500 for m60 and same for manual tranny..... OKAY

[JGood]

Thanks for the info on BBB, I'll have to look them/contact them as I don't want to run a dual-mass flywheel with it's rubber center section that wears out.

Where did you find e39 540i flywheels for under $250 shipped?

car-part.com, ebay, forums, etc..

I posted a WTB on bf.c a few weeks ago, and Travis from Bavarian Auto Recycling responded. I called him up about 10 minutes ago, he said he has a bunch of the e39 540i flywheels, just sitting on the shelf because nobody ever asks for them. He checked them all for play between the halves and hot spots on the surface, picked out the best one, and is getting it to me for $100 plus shipping. Seems like a cool guy, we BS'd about my swap for a bit, and he told me he's building an s50 e30 truck conversion. If you want to call him, send me a PM, I'll give you his number.

[Jean]

Thanks for the info on BBB, I'll have to look them/contact them as I don't want to run a dual-mass flywheel with it's rubber center section that wears out.

Where did you find e39 540i flywheels for under $250 shipped?

[JGood]

Good deal on that clutch kit, maybe I missed it but is there a single mass B30 flywheel that you guys have found or some other flywheel that works with this clutch kit on M60s with the 5speed tranny??

I contacted BimmerWorld because I saw that they had an e34 530i JB Racing flywheel on their site. I asked them if that was for the euro m30 car, or the US m60 car, and if they know if the stock m60b30 clutch would hold the m60b40 power. This is the response I got:

"No the E34 530 only came in a m60B30 the flywheel would be for that motor with the stock clutch. The stock 530 clutch should be fine for an M60B40 motor."

If you visit JB Racing's website, you'll see they actually have a flywheel listed for the e34 530i m30, but not for an m60b30. So I'm going to assume the guy at bimmerworld was just wrong.


Anyway, there is a company in the UK selling actual m60b30 lightweight flywheels, basically made to order... to use any PP you desire. The company is Big Bavarian Beauties, and the price he offered to me was £420-00 delivered. He also recommended getting the flywheel set up with a different clutch as they've seen slippage issues with an m60b30 clutch behind the 4 liter.

I scratched the LW plan due to my budget. e39 540i flywheels can be found for under $250 shipped.

[Jean]

Good deal on that clutch kit, maybe I missed it but is there a single mass B30 flywheel that you guys have found or some other flywheel that works with this clutch kit on M60s with the 5speed tranny??

[mkcman17]

to edit my post one more time here, i just discovered that my friend has a full CnC machine at his god dang house. does anyone have dimensions for motor arms and/or 6spd trans mounts? i might be able to have a few limited sets made at reduced cost (at least cheaper than .de stuff).

[JGood]

i'm putting in my order for a clutch this week. because of the non-custom nature of the 5spd, i've decided to at least start that route and possibly go 6spd later. to beat a dead horse one last time, if i'm planning to use either a b30 or m/s62 240mm flywheel, i can use an m52 clutch and PP, right? i was going to pick up a stage 1 328 kit good for 300+whp.

I'm getting ready to do the same. I'm going with a stock e39 540i flywheel (LW is out of the budget). And I'm going to give this clutch a shot...

Sachs organic performance clutch

http://www.autopartswarehouse.com/sku/BMW/328i/Sachs/Clutch_Kit/1997/Base/6_Cyl_2-dot-8L/S2K7020601.html?intcmpid=Product+Listings+Clearance

Not sure how it will work out, but for $230 shipped, it won't be a huge loss either way. There are guys running 300whp turbo 328's with worn stock clutches without a problem, so I can't imagine 260whp with this sport clutch will be an issue.

Thanks again to Bruce for figuring out this combo!