My LQ4/T56 540i Sport conversion thread

[James39]

Well, progress has been made, I have a car.

242,xxx on the odometer.

Found this nice candidate and picked it up this morning. Engine and transmission work, but IMO, both need a complete overhaul (rough idle, oil leaks of every kind everywhwere.)

I plan on freshening up the suspension during the swap, and will hopefully rebuild the factory diff with some 3.64 gears.

Came with some 19" weels too, that I don't think I want to use. I'm kinda partial to these stockers!

LQ4 is topped with LS2 heads and Lunati .651 lift 227/231 duration @ .050

Hauled ass in the '68 C10!!!

Looking to daily drive this thing when it's done

[Schitzo]

Great starting point. You will absolutely enjoy a LS E39. Keep us posted.

[James39]

Will do! Yours and 2 or 3 others were my inspiration! Did you get your factory gauges and AC working with the GM computer?

[rao]

Have fun

[M5Hunter]

classy, e39's need FI cause they have room, I'm just sayin' =)

[James39]

classy, e39's need FI cause they have room, I'm just sayin' =)

If the engine weren't already built, Maybe I would have kept the lower compression heads for such activites.

[James39]

Well, there's no turning back now.

The LQ4 is out of the last vehicle and ready for C6 vette acessory package and LS6 intake. Doesn't look like much, but it's a beast!

T56 was rebuilt and new Diamond clutch and hydraulics have arrived. Still waiting on my MGW shifter.

It was interesting taking things apart, wasn't sure if I was supposed to push, pull, twist or yank, but it wasn't too bad.

There's not a whole lot more for me to do up top (at least I don't think.)

Were the cars built around these engines? The LS is going to look small in there!

The pics aren't all that exciting, but I'm glad I was finally able to get this thing underway...

[douglee25]

Woot!

[James39]

I have it linked up to the picker, but man, that thing is in there tight! -- Ready to throw a grenade under it to try to make the pieces a little smaller.

Such a relief... That engine mount looks good enough to re-use, right?

Time to clean up and make preparations.

[Bmwman528e]

LOL that motor mount is CASHHHHHHHHED. Looks like tomorrow you will be taking those out and going to the store to buy 5 gallons of degreaser because you have got some scrubbing to do in there Nice progress.

[James39]

LOL that motor mount is CASHHHHHHHHED. Looks like tomorrow you will be taking those out and going to the store to buy 5 gallons of degreaser because you have got some scrubbing to do in there Nice progress.

I'm thinking about using the pressure washer and some simple green. As dirty as the bay is, you can imagine the amount and types of fluid that were drizzling out of this car everywhere when I got it. The steering box and hose connections there are dry, that's the only thing I was really concerned about

[robtheviking]

Hello mate, stumbled across from your link on the coding forum. Looks like you are well underway with the swap already! Will bookmark this thread!

Already having a manual box in the E39 will make the coding far easier, trying to code the auto out is a bit tricky.

Best of luck mate!

[James39]

Hello mate, stumbled across from your link on the coding forum. Looks like you are well underway with the swap already! Will bookmark this thread!

Already having a manual box in the E39 will make the coding far easier, trying to code the auto out is a bit tricky.

Best of luck mate!

Thanks man! - I'll be removing the BMW DME and replacing it with a 2004 Chevrolet truck engine computer and using a stand-alone wiring harness to operate the engine.

It's great that everything else seems to work without the BMW engine computer connected.

[robtheviking]

Be aware mate. The DME is tied to both the EWS and the ignition coil. I'm guessing you'll have to bypass the immobiliser fit an aftermarket system?

[AutoRotate]

Yes, yes, yes! I need more inspiration to start taking the steps for my own swap! Keep up the progress

[James39]

I'm guessing you'll have to bypass the immobiliser fit an aftermarket system?

I have no idea, but the engine harness I modified on my LQ4 is currently wired to operate on only 3 12v inputs (always hot, hot in on and start, hot in start only)

I am going to attempt to use as much of the factory power wires as possible from the ignition switch (or other circuitry that is controlled by the ignition switch), and will figure out ways to bypass things only if absolutely necessary.

I should be able to tap into the factory fuel pump relay on the bmw and operate it through the GM engine computer.

I've had this engine, wiring harness and computer in another vehicle and it's surprisingly simple to make it work without it being tied into anything else.

Yes, yes, yes! I need more inspiration to start taking the steps for my own swap! Keep up the progress

The only thing holding me back is waiting on parts to arrive. If all goes well, I should have the LQ4/T56 sitting in it's new home this weekend

I took the easy way out with a number of things by just buying things new. My $ budget is much larger than my time budget (that just means I have no time, it's not to imply that I have a lot of $ for this swap )

This is about as cleaned up as it's going to get... good enough for a driver

[robtheviking]

All of the wiring you need will be on the connector that the DMW would have connected to, it's just a case of sitting down with WDS and working out what you need to tap in to. Are you planning to pull the DSC out of the system or re-instate it? Also, out of interest, any plans for an LSD?

[Bluebimma]

Good luck with the build

[James39]

All of the wiring you need will be on the connector that the DMW would have connected to, it's just a case of sitting down with WDS and working out what you need to tap in to. Are you planning to pull the DSC out of the system or re-instate it? Also, out of interest, any plans for an LSD?

DSC is going to be left out. Maybe a project to work on later down the road, since the GM PCM has capatility to use traction control. Just not sure if the signals from BMW DSC are anything I can use (I highly doubt it!)

I have the Bentley manuals, so I have pretty much found the wiring I need to know for now... Like I said before, it isn't going to take much

LSD is way too much $ right now (looking at a $3000 bill for that). I picked up a used 3.15 diff from Bavarian Used parts for $270 delivered!!!

I have the new oil pan on, the trans is all bolted up. Not much left to do before dropping it in.

[robtheviking]

$3000?? No no my friend! A mate of mine from the 5 series forum i belong to installed an LSD into his 540 for less than £500! Here's his thread telling you how to do it!

The trouble with pulling the DME is a whole pile of other stuff talks to it.

[James39]

$3000?? No no my friend! A mate of mine from the 5 series forum i belong to installed an LSD into his 540 for less than £500! Here's his thread telling you how to do it!

The trouble with pulling the DME is a whole pile of other stuff talks to it.

Perfect, and ill already have a spare e39 diff to build and swap right in!


I looked up the immobilizer functionality, and the only thing I think ill lose is the feature where the starter relay disables itself if rpm signal is coming out of the dme. Once the starter relay is triggered by the master module, the rest of the immobilizer functionality is left for the DME to decide (ignition coils and fueling is controlled by the new GM computer, so it's not an issue). I have the AC,tach and coolant temp figured out from researching what others have already done. The only thing that wont function is the MPG gauge, and I think I can live with that in order to keep it simple


BWMman528e swap kit is the way to go if you want this done quickly

Snapped off a crossmember mounting bolt??!?!?? That kind of pissed me off, but other than that the install went very well.

Shimmed the new clutch to have 1/8" free play, installed bellhousing, oil pan, engine stands, and she's in.

Only problem was the load leveler was in the way, so I had to stop progress and make 2x6 wood jacks to hold everything up while I swapped the load leveler for a piece of regular chain.

Next Steps:

Remove driveshaft and differential, measure for driveshaft length

Figure out what to do for a shifter (either go to F-body, or make the aftermarket MGW work)

Hook up new clutch master cylinder

Install accessories and measure for new power steering hoses

Install headers

Fab exhaust

Attach/modify fuel lines

Electrical/Wiring

Cooling system/radiator

Turn key! --

AC can wait, but I'll keep it in mind while doing all the other things.

[robtheviking]

Wow! Amazing how much space there is left in that engine bay! You're making good progress mate, look forward to further updates!

[Bmwman528e]

Looks like Im gonna have to design a Turbo Collector next.... !!!!!! Working on this motor will be such a breeze. Look at all that space. I just stood in my garage and stared in the engine bay in awe for like an hour when I bolted mine up the first time.

[James39]

Tell me about it -- All that space really needs to be filled in with something else

[jmil74]

"AC can wait"...must be nice! LOL

Seriously, awesome progress, keep it up!