E46 or E39 for LS swap

[Damon Forrer]

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Guys,
I have a 5.3 LS in my garage that I have built from the ground up. I suspect it will make about 400HP at the crank with flat top pistons, LS6 cam, intake and fuel injectors and ported and polished heads. I built it to learn all I could about the LS engine, but now I am to the point of thinking about what to put it in.

Previous project was a 5.0 in a Miata so I am reasonably competent when it comes to this kind of stuff.

Originally I was thinking an older Jag XJ6 or Volvo 240, but now I am leaning toward a 3 or 5 series BMW, specifically a E46 3 series or E39 5 series. Either option can be had for a song if I can find one with a dead engine.

My question for you guys is what would be the better option? More room to work with the 5 series, but better power to weight with the 3 series. Not sure if I want to go auto or manual. I love the idea of being able to remove the radiator core support for ease of install. making the LS PCM communicate with the BMW dash will be a challenge, but this whole project has been a learning experience so not too concerned there.

I understand the 540 is harder to swap because of the steering box, is this something I should be concerned about?

Is it possible to mount an LS up to the BMW 6 speed used on a 540 with some sort of adapter plate?

[Liquidity]

There’s not necessarily more room in an E39 but more importantly, there aren’t anywhere near as many options for that chassis. The E46 has tons of support and a swap could probably be done in a weekend without having to fabricate anything except for exhaust after the collectors.

[E39540V8]

I think the car you pick will depend on what you want from the car. The E39 is spot on for me as I have 4 kids to transport around and need the boot space for their gear. If you want a 2 door that is a bit more sporty and don't have back seat passengers, then that is a better choice.

[Liquidity]

Also, there are a couple options to use the BMW trans behind the LS, but not the ones from the V8, only the I6 transmissions. They’re European companies and really for the European market where the t56 is super rare and super $$$$. You’re better off just using a t56, in the end it’s not going to cost any more and it will hold a lot more power.

[Damon Forrer]

Guys,
Thanks for the advice.
I think the E46 would be a better choice for me, this will be purely a project / toy for me as I have a ND Miata daily driver in the nice weather and an Xterra for winter / hauling / passengers.
I rebuilt the 1.8 liter engine in an E30 about 10 years ago, my girlfriend had an E46 as did I some years ago so there is some sentimentality attached to the 3 series.

Sounds like I need to start looking for a T56.

- - - Updated - - -

I actually bought this 540 last year with the intention of doing the swap, but then decided to have a go at replacing the timing chains and rebuilding the VANOS. All went well, car ran beautifully when done, so I sold it.

[AdamBath]

On E46 you'll need to address the rear subframe mounting points, unless you get a facelift, and even then probably still worth reinforcement considering the added power.

Even given that though, I'd go E46.

[Damon Forrer]

Good call Adam.
Will the E46 diff stand up to the power of the LS? I assume a M3 diff is the preferred option but until then?

[AdamBath]

Good call Adam.
Will the E46 diff stand up to the power of the LS? I assume a M3 diff is the preferred option but until then?

I think it will, but keep in mind it's an open diff, with no OEM/easy LSD option.

[Damon Forrer]

What is the typical diff swap? a ford 8.8 IRS?

[wanganstyle]

Good call Adam.
Will the E46 diff stand up to the power of the LS? I assume a M3 diff is the preferred option but until then?

A properly setup e46m diff will handle 1krwhp over reasonably reliably.

[Damon Forrer]

Wow,
The T56 is not cheap, the ones I have seen are around $2000 with no guarantee as to the condition.
Maybe I should go with a built 4L60E and not have to worry about clutch hydraulics etc?

[Liquidity]

It’s $2,000+ just for the adapter and clutch to use a BMW transmission, plus you still need to supply the transmission. And I don’t know why you’re asking us if you should use an auto, you’re the one that has to drive the thing.

[Damon Forrer]

Good point, I am still trying to like things up in my head before I make any moves. At least any expensive moves....I do appreciate all the input though.

[AdamBath]

Wow,
The T56 is not cheap, the ones I have seen are around $2000 with no guarantee as to the condition.
Maybe I should go with a built 4L60E and not have to worry about clutch hydraulics etc?

Nissan CD009's have become a popular trans for LS swaps lately, but requires an adapter and a T56 bellhousing.

http://collinsadapters.com/index.php...ter-plate.html

They're not too hard to find in decent shape. Might be able to save money there and still have a great trans.

[unnatrl]

You can also swap the front suspension over to the 6 cylinder parts. It bolts right in. Jesus Freak builds a sweet set of mounts. An Autokraft oil pan fits like it was built for the E39. T56 or 4L80e works well. Sonnax makes a flange that uses a 1350 joint and bolts right to a 540 6 bolt differential so you can use a 1 piece driveshaft. Wiring is covered in a thread on BFC. You can bolt an LS into an E39 just as easy as an E46. I love my E39 over the previous E36 or E46. I built a Turbo 6.0 E39 and absolutely loved it. O tore it apart to put the drivetrain into a 67 Mustang would still be in the E39 otherwise). Still have all the big stuff required to swap my new daily when the time comes. You won’t be disappointed.

[Damon Forrer]

There seems to be an abundance of E39's around here for $1000 or less, but you're saying if I buy a 540 that I sould swap out the subframe for one from a 6 cylinder? So if I want to do an E39 I should be looking for a 525, 528 or 530?
Are the Jesus Freak mounts for a 6 or 8 cylinder car?
What are the options for headers or exhaust manifolds?
What website is BFC?
Thanks for your advice, I have been going over this decision in my head for about a year now so everything helps.

[AdamBath]

There seems to be an abundance of E39's around here for $1000 or less, but you're saying if I buy a 540 that I sould swap out the subframe for one from a 6 cylinder? So if I want to do an E39 I should be looking for a 525, 528 or 530?
Are the Jesus Freak mounts for a 6 or 8 cylinder car?
What are the options for headers or exhaust manifolds?
What website is BFC?
Thanks for your advice, I have been going over this decision in my head for about a year now so everything helps.

BFC is the website you're on right now

Believe Jesus Freak's kits are for I6 E39s.

[Damon Forrer]

Doh!

[Damon Forrer]

Im back guys.

A few weeks ago I picked up a rust free 2003 E46 (330Ci) for my swap.

Pulled the engine and auto trans last weekend and now trying to sort out the bits and pieces I will need for the swap.

I am pretty sure I want to go with a T56 manual gearbox.

What is the preferred way to adapt the DBW BMW gas pedal to the cable operated LS throttle body? Is there an earlier model cable type gas pedal that will adapt to the E46?

[Matt330LS]

Im back guys.

A few weeks ago I picked up a rust free 2003 E46 (330Ci) for my swap.

Pulled the engine and auto trans last weekend and now trying to sort out the bits and pieces I will need for the swap.

I am pretty sure I want to go with a T56 manual gearbox.

What is the preferred way to adapt the DBW BMW gas pedal to the cable operated LS throttle body? Is there an earlier model cable type gas pedal that will adapt to the E46?

Switching from auto to manual I'd look for a clutch pedal setup from a wrecked manual 330. As for the gas pedal, the early E46 (1999) 323 and 328 used a cable operated pedal setup. That's what I'm planning on using in mine as soon as I can find one.

[Liquidity]

99-00 e46 were cable throttles. All you need to do is get the cable and pedal from one of those.

[Damon Forrer]

I have a pedal assembly on order from Pelican Parts, Didnt't have much luck finding one used.

[Liquidity]

Think I paid $15 from the junkyard.

[Damon Forrer]

The junkyards around here get picked dry pretty quick, especially of BMW parts. I did find one on craigslist but the guy wanted about the same amount as I paid for a new one.