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E46 M3 S85 swap thread


i_love_cars

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1/8/2019 Update - I am changing the status of this to "on hold". The donor car is being parted out this week but I am holding on to the engine, ECU, CAS module, EWS module, etc. basically all the bits needed for the swap. It may be a year or two before I do it, or I may end up selling the engine for cash at some point down the road, but for now I think it makes sense to just keep the stuff I need for the swap since I can break even on the donor car purchase simply by parting out everything else. The transmission has already been sold for 2800 which is nearly half of what I paid for the car. Unfortunately my house needs new windows and a couple doors and I have stupid fancy windows that is going to cost me at least $45k to replace everything. My hope is that by sometime in 2020 I can re-consider this swap project and pick it up again. 

I am still preparing for the swap by putting a 4.10 2-clutch diff in the E46 this spring since it needs a new diff anyway. This is the diff that we would be using when swapping the S85 in, and it makes sense anyway since BMW M-differentials suck horribly due to their locking being based on hydro upon slippage during a turn as opposed to any sort of pre-emptive locking like a proper LSD from diffsOnline will do. 

 

12/17/2018 Update - I am canning this project and parting out the donor car for profit. I originally had a top-end budget of gross cost of 30k including the donor car. I have talked to some other shops who have done this swap multiple times with full OBD2 compliance, a/c, etc. like I was planning and there are some budget items that are just wrong on the estimate. Realistic gross cost should be factored at about 40k and even that may be a bit light. Our original cost estimates were based off of Epic's swaps, but that doesn't really factor in that Epic builds race cars that don't need to be emissions compliant, nor do they need to worry about stuff like ground clearance. I learned that without modifying the frame rails, the oil pan on the s85 will sit too close to the ground for a street car, so you need to do some fabrication work to modify the frame rails accordingly. I have also learned that whether it's using the E60 ECu or the Awron standalone, both are a nightmare to wire. We were under the impression that the E60 ECU would be a lot more straightforward, but I'm hearing otherwise from reputable sources. 

So I am going to use the profits of the partout to pay for an upgraded LSD (my current diff is in really bad shape), and cover the cost of my BBK. 

 

12/15/2018 Update - The bottom of this post is updated and will continue to be updated with full list of budget items for the build

 

I already have an E46 thread but this feels like it's going to be worth a separate post. I want a dedicated thread where I can post information about the swap as it happens and document everything. 

I've been talking about a swap with E-fab Motorsports for a couple months now, knowing that a V10 in an E46 would be a dream to park next to my S65. Research has been done, and other shops who have done these swaps have been contacted for information. We know what the budget should be, and I'll be working with E-fab such that this car can hopefully be used to help promote Eric's business in the Chicago area and potentially beyond. He's done a lot of good work for me this past year and we've developed a good relationship, he's able to fabricate and has a great wiring tech so I feel like this is a sound partnership for the swap. 

What is the goal? This will be a complete swap with fully functioning amenities - A/C, heat, power windows, push button start, etc. Nothing is going to be haggard or half-assed. The custom exhaust will even be valved with an in-cabin F-you button to activate/deactivate. The swap is not done with a standalone ECU/programming. The car will use the stock E60 M5 ECU, flashed by Epic and wired in to the E46 harness and dash cluster. 

Some key points of consideration:

1) stock e46 M3 steering rack can be used with an S85 from this 2008 donor because by 2008 BMW had moved the CAS module out of the M5 steering column. This is enormously helpful because it allows the swap to go on without any suspension modification or steering modification 

2) The engine fits with no modification required to the oil pan, and stock S85 headers also fit although it is tight. 

3) Fabrication requirements are limited mainly to custom engine mount brackets, some subframe modification, and making a driveshaft/shifter assembly. A couple odds and ends need to also be fabricated like custom power steering lines which is about 400 bucks, and some custom coolant hard lines to the block

4) A 6MT from an E9x M3 can be used in this swap as it bolts right up to the S85 block

Most of this basic info has been procured from Epic who has done a couple of these swaps, and they also provide a flash tune for the ECU for this swap

Now, on to the real exciting news - Steve at Blunt Tech posted a 2008 M5 on R3V a few days ago with only 33k miles on it, totaled due to side impact (see photos). He sent a video of the car starting right up and mechanically it is all good. Other than being an SMG, it's a perfect donor. It was only $7k which I am sure I can recoup most of by selling the Dinan exhaust, rear end, low mileage SMG, suspension, wheels, and probably the currently ruined interior to a tracksuit-wearing russian with a 530i (E-fab made up the part about the russian but I'm taking credit anyway).

The car has been acquired as of now. Sometime over the next month I'll likely be down there in the shop helping Eric part out the shit I want to sell. The actual swap work will likely begin in January/February and hopefully be done by April. 

Before anyone asks the inevitable question of "what are you gonna do with your S54 engine/trans/harness?" - I don't know for sure yet, but the current ideas are this:

1) Eric at Efab needs an engine for his E36 so we may be working out a deal for the labor on this swap by giving him my S54 parts so he can build his E36

2) Buy an E30, do an S54 swap and rejoin the cool kid E30 crew so I don't feel out of place when rolling with TJ, or more than likely flip it on BaT for double my money and make a $10k profit which would make my entire S85 swap....basically free lol

3) Sell it as a swap kit to a person in need who I don't deem to be a shitfuck. 

For posterity, I have to post 1 pic of the E46 as it currently is. Pics of the M5 donor are below:

IMG_2350.jpg

 

m5_1.jpg

 

I have talked with Efab at length and we've gathered cost information from several parts providers for everything that needs to be customized at this point - things like the radiator, ac lines, oil cooler/lines, etc. which all are going to have to be custom built. This list is not exhaustive and will be updated over time - it includes what we feel is 98% of the necessary parts for the build currently. 

It is worth noting that this does not include labor costs for things like R&R the engine between the S85/E46, or labor to part out the S85, or installing the additional parts on the E46 like the new diff, trans/clutch, etc. Most of that is being given to me for free by Efab since the expectation is that promotion from this build will likely net them some new deep-pocketed customers in the future.

PRICING / PARTS BREAKDOWN:

 

 

 

 

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5 minutes ago, suspenceful said:

I love this because when the day comes that you're ready to sell the car, I can buy it.

Thread winner 😂😂😂

39 minutes ago, straight6pwr said:

so does steve owe me a finder's fee?

this is awesome, cant wait to see the progress

 

You probably should. I talked to him on Friday and he said he had a line of people who wanted it but nobody had paid yet - I assumed that while I was spending the next few days planning this all out in a rush, that it would sell. Then I talked to him on Monday and he says it's just a bunch of idiots trying to get a loan for a $7k salvage M5 with no title and not even a salvage certificate. If not for me who knows when he'd actually sell it 😂

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Picked up a really clean E9x 6MT just now on ebay. 56k miles on it at $1800 shipped is maybe 100-200 bucks overpriced but it obviously includes the knick knacks like shift linkage, etc. as opposed to being just a bare transmission. May need to end up fabricating a custom shift linkage anyway but I'd rather have the stock parts with the transmission if I can, so this makes sense I think. 

e93_trans.jpg

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So, updates. Main thread has been updated with a spreadsheet screenshot of all the cost breakdown for everything. It will be updated over time as needed but at this point we have covered just about all the bases. 

The transmission I had got on ebay arrived with a giant crack in the bellhousing among other problems - basically everything got fucked up by the freight carrier. So I have been refunded for that and am back on the hunt for a transmission again. If anyone catches a beat on a decent E9x 6mt transmission, let me know.

I have a standing order in with BimmerWorld for a set of BE bearings which is somewhat entertaining because they didn't even take payment info and said "anything we authorize will likely expire by the time bearings actually get in stock" since BE is constantly on backorder for S65/S85 bearings upgrades.

The majority of other updates are essentially already documented as a result of the pricing spreadsheet - basically have just been talking with vendors for making custom parts and updated prices accordingly based on what they said. 

Part out of the M5 begins right away in January, and I already have the SMG sold for $2700 and in January will be posting up in the M5 forums and chicago area BMW FB groups probably with official part-out lists. 

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Engine swaps are no joke. My warmed over M52 swap was "easy" and still cost a few grand. Putting together costs to S54 swap an E36 had costs going north of 11k with me doing all the work. 

The V10 E46 dream is dead, but it died because of sound judgement. There is still a well sorted E46 M3 track car with a healthy engine in his garage, so the story still has a happy ending.

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5 hours ago, Rekpoint said:

Yeah... How does it feel to disappoint the whole community....

I'm kidding. 😂

No, no it's definitely a big disappointment to quite a few people lol. You can say what we're all thinking - it's ok 😂

9 hours ago, Jdesign said:

😪  Well you have more self control than I do. Sad to see it go, but im sure it was a good decision. 

I think it was the right decision. 40k for this build is a lot indeed

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The dream is still alive. I have decided that (at least for now) I am keeping the engine and all swap-related parts at Efab Motorsports. Eric will store them for me indefinitely. So I'm going to part out everything else like I planned on in order to break even on the purchase of the car, but at that point as long as I've recouped my 7k, then I don't see any harm in hanging on to a 33k mile S85 that works, assuming I will one day swap it. I don't see myself being able to replicate this kind of a deal for such a low mileage , functional example so it's hard to sell the engine. 

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7 minutes ago, i_love_cars said:

The dream is still alive. I have decided that (at least for now) I am keeping the engine and all swap-related parts at Efab Motorsports. Eric will store them for me indefinitely. So I'm going to part out everything else like I planned on in order to break even on the purchase of the car, but at that point as long as I've recouped my 7k, then I don't see any harm in hanging on to a 33k mile S85 that works, assuming I will one day swap it. I don't see myself being able to replicate this kind of a deal for such a low mileage , functional example so it's hard to sell the engine. 

Maybe I could put it in a van for you...

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