E46 Fanatics Forum banner
Status
Not open for further replies.

2004 325xi auto turbo project

156K views 355 replies 75 participants last post by  gurov 
#1 · (Edited)
2004 325xi auto -> 5speed turbo with megasquirt

gonna revive this thread. i've more or less finished my supra (for the time being, until the bmw runs).

i've received a bunch of PMs since i've posted this thread about stuff. unfortunately, I lost all the original build pictures with the bottom mount, and the struggle for topmount.

i'll post some pictures here with progress, and update the first post for those interested.

i have no idea what's written in the thread anymore, so i'll simply repeat it:

I picked up the car sometime in 2007, 2004 325xi automatic.



it was comfy, but kind of gutless.

the automatic trans really didn't help either:



fastforward a few years ago, i decided to turbo it.

first attempt was with a straight forward bottom mount turbo on an ebay cast manifold, but who cares, bottom mount was a pain in the ass. the oil scavenge pump made me super nervous, and it just sucked to work on.
intake plumbing was also a massive pain due to the crazy stock intake maifold with the throttle body being hidden away below runner 3-4. the only neat thing about that manifold was how easy it was to get to the injectors. i ended up managing the engine with megasquirt3 and terribly hacked up stock harness. the automatic transmission was slightly modified to hold a bit more pressure, but i really didn't push it that much, only about 9 psi was all it ever saw.

the automatic transmission was managed with MegaShift, another megasquirt project that handles the auto transmissions, that was a massive pain as well, code was buggy and just a bad driving experience, so the decision to swap to a manual was made. then i let it sit for 3 years in the garage, or so.

here's all the juicy bits that people will likely want to see:

top mount turbo:



some of the downpipe pieces, the exhaust is vband from a pipe that's attached to the turbo (it's an ebay 5 bolt flange), vband was the only way to make this work. it's 2.5" due to space.





the manifold is a TCD unit made for m50 or m52 engine, mounted upside down, The manifold has a T4 flange, and one of the standard wastegate flanges. To get the turbo up to where it is, there are 2 extenders, a T4 to T3, and T3 to T3



it was the most straightforward way i could get it to mount, and it fits quite nicely.

naturally, with top mount, oil feed is easy:




and oil return is also, easy, as it's gravity powered.


the transmission is a 5 speed ZF (i think), bonus transfer case (non X-drive) bolted to the transmission already (on the top)



when i got it, 5th would not engage, it turned out that the 5th notch piston was completely frozen, perhaps cause it was cold, so i pulled them out, and now waiting for that mechanism replacement to ship from pelican.

clutch disk, cover, and flywheel are some sort of M3 items:





there's obviously other manual swap bits, new pedals, master/hydraulic lines, shifter, new bushings for everything. etc, i won't bother with those as you all have seen that stuff.

now, one of my annoyances when working on the old setup was the intake manifold, so i looked around and got one of those thai M50/M52/M54 manifolds, and it actually fits !
here are some pictures of the new intake manifold, fuel rail bracket, and cable throttle holder bracket:





and mounted on the car, for test fitting:



it is a stock deadhead (returnless-ish) fuel rail with some 660cc MSD injectors with the right connectors to use with stock harness. mount points have been changed, and i made that nifty fuel rail bracket to hold it all down. but a different fuel rail fits (with entry and exit). using the stock fuel pressure regulator/filter that comes with e46 and mounts under the car (boost-referenced)

now, for the management.

originally, when the car ran on megasquirt3, i had rushed the installation, and tapped all the wires under the hood at the harness, soldered to them, cut them, made it look gross, and basically had a really shitty mess of wires that was a pain to diagnose. ms3 worked perfectly fine, however, even ran both VANOS solenoids with tuning for that. I had J&S ultrasafeguard that managed knock, stock coils were ignited using some sort of toyota camry igniter, that megasquirt ran. as far as tuning the engine to run well, megasquirt was amazing, the wiring I created was not.

this time around, i'm doing it slightly different, i'm taking a stock ecu, tracing where stuff goes inside of it on the connector, and putting connectors on the outside that megasquirt will plug into

here is the ignition transistors taken over and wires soldered to the current-limiting transistors.



there is a small surface mount resistor near each transistor that the stock CPU controls these transistors via that has been desoldered.

the same thing has been done to the injector drivers here:


there are two automotive driver ICs with 20 legs each, that control 3 injectors each. legs have been lifted, and i soldered to the bottom of the connector.

same will be done to the vanos solenoid drivers, fan driver, fuel pump driver, idle controller, knock sensors, and whatever else comes up.

the whole point of this is to use a stock engine wiring harness without having to modify it.

i likely missed a thing here or there, if you have questions, let me know, and i'll go take pictures of what i've done, or explain what the plan is.


more here: http://forum.e46fanatics.com/showthread.php?t=773653&page=14#278 <--- go here
 
See less See more
21
#30 ·
mostly completed engine bay (no more maf)



j&s safeguard to protect engine from knock:






GPIO kit for transmission control has been ordered. (megashift)
 
#32 ·
nothing much really... i just want to ensure the stock ecu won't leave me stranded by disabling the trans, i also do not want to destroy the trans by running it in an unknown state. It appears to be in a failsafe mode where it's shifting very firm, but i bet that's designed to save the trans. The little gear icon is lit next to the D indicator on the cluster. But it shifts fine. i drive this car when i can now to the store for food and parts and such, tuning and logging. as i've said before, there won't be a dyno, perhaps until much much later.

i'll get a video next time i drive the thing, hopefully the blowoff sounds will come out with the window open.
 
#36 ·
no one said it can't be done just that it would take a bit of money, time, and experience that 99% of people on this forum certainly do not have or aren't willing to expend. This man, however, falls into the other 1% :)
 
#40 ·
Hey

very awesome project! Glad to see it going.. wanted to ask why it wasn't possible to use the bmw coil's with mega squirt? Does the megasquirt put out a +12v signal, and the bmw coils are expecting the signal wire to be grounded, such that you'd need to build a signal inverter so to fire them? Is the stock ecu doing the tach, and vanos and nil else?

Nice indeed - btw where did you source that exhaust manifold? I've been looking for something to mount a small garette turbo I have , that manifold would be perfect!
 
#45 ·
i was simply too lazy to troubleshoot the bugs from firing the bmw coils. they're just normal dumb coils without an igniter, so it's totally doable to run them with megasquirt and people have done it. I took the easy way out and did LS1 coils, cause i've done several cars with them, hence i know how they work and they're easy to work with.

stock ecu is driving tach, speedo, and whatever else is still connected to it. vanos is unplugged. once i get more bugs worked out of this, i'll call upon the seattle circuit fellow to provide me a with a dual vanos controller to see what that will get me.

the manifold is ebay. i do not like it. i just ordered a turbocharging dynamics manifold today along with a t4 to t3 cast iron adapter.

the problem with my manifold, or i suppose with my choice of parts is the fact that i'm using a very much hacked together wastegate, where i even had to drill the exhaust housing of the turbo for the hole, apparently that wasn't big enough, so now there's boost creep and it's overboosting.

i've got a proper tial gate laying around, and with the turbocharging dynamics manifold (which will hopefully fit, we'll see) i'll be able to use the external gate and control the boost properly without hitting self-imposed boost cut.
 
#44 ·
speed density, but it's set to percent baro, so atmospheric is always 100 ""kpa"", which now becomes "fuel load".
 
#46 ·
#48 ·
finally some pictures of it. went out today to get some groceries.



 
#52 ·
yea, the manifold I'm getting from tcd is actually an s52/m52 variety, I'm pretty sure it will work, hopefully the wastegate clears the wheelwells. as I realizedm the engines are mounted at diffefent slant angles, so I might have to modify my engine mount once again.
 
#53 ·
Congrats on the project. Its nice to see someone on the forum that actually knows what they are doing. I have been telling people for years that you could do this and alot cheaper then what they think it would cost. If you know what your doing and you fab everything up yourself like the op I can guarantee this cost a good amount less then the supercharger kits out.
 
#54 · (Edited)
Individually, people need to decide what their time is worth. If you have lots of time, and want to save money, DIY makes sense. If you have very little spare time, kits make a lot of sense.

Then there are fanatics that like to spend lots of money and time, because they just like to do things "their way".....
 
#55 ·
whoever wanted information on the headers check my sig.

On a seperate note one day I will have money for another car and i think my 323i may undergo a similar construction, but the biggest issue is having the tools to do the job.and the space to store a car for a while since this is definitly not a day project.
 
#57 ·
the biggest issue is having the tools to do the job.and the space to store a car for a while since this is definitly not a day project.
1000 sq/ft for one car, and it wasn't enough for me. Car projects eat space.

Decided to build a 2nd garage at the house for this kind of thing. It's a balance between property setbacks, and how much my wife/neighbors will tolerate for size. (I live in an acreage area with covenance stipulations) My neighbors thought I was joking about buying the lot behind me to extend the garage onto it...30' X 150' isn't too big right?

Turbo projects can get expensive!!!!!!
 
#60 ·
tore back into the exhaust bits of the car today, it was overboosting on the internal gate i rigged up, so i bought a TCD manifold, and a t3 to t4 adapter. just for kicks i reversed the manifold, and it looks like if one gets a t3/t4 adapter with the right angle and the right height to get the compressor housing to clear, it would be possible to do a topmount setup, while keeping the AC lines undisturbed. tial gate mounts cleanly on the bottom of the manifold, just have to relocate the main pressure port on the gate to a different spot and plug the original. i'm not sure i'm going to go through with the topmount idea, but it's def possible. 2.5" pipe fits between the rear of the manifold and wheelwell/firewall heatshielding fairly well
 
#62 ·
whoaaa how did i miss this! Subscribed! I've been trying to do this with a buddy of mine... his company (Neukin dot com) specialize turbo manifolds and turbo kit components. Custom intercoolers, turbo manifolds and integration of blow off valves and wastegates, fabrication of race parts, etc... We just didn't have the time (together) and yet here you are doing it by yourself! Amazing!! I'm excited to see this fully develop!
 
#64 ·
This is starting to resemble a e30 turbo build with megasquirt very interesting.
 
#65 ·
megasquirt 3 (as in ms3) + ms3x for sequential fueling/ignition/idle control/other stuff, i'm also in the process of programming a GPIO for 5L40E auto trans control.

also, looks like i have to go topmount with this or die trying.

TCD is meant for e36 it seems with the different angle engine, so on e46, the giant tial wastegate thing hits the body.
 
#66 ·
Any concerns with the extra power damaging the xDrive system? I know it's much simpler with a RWD setup, but you have 2 diffs to worry about as well as the extra compenets in the gearbox to transfer power up front. Also, any modifications to the ABS/DSC system?
 
#67 ·
hmm... well, from what i can tell, the components aren't made of crap and they're also shared with some more powerful vehicles.

there's actually 3 diffs... cause there's a center diff. i'm not sure if the DSC system is still going to be functional with all the control that's been taken away from the ecu.

my primary concern is really the gearbox, but hopefully with proper tuning of the transmission controller, i will be able to put some power through it. the gearbox is rated at 390 ft/lb max by GM (as390r <--- the 390 in there).

i just ordered a few parts that will hopefully make it painless to install the topmount setup.
 
#68 ·
Thank you so much for the photos, it just adds a whole new life to the thread and conveying your project to others. I am liking your idea of going top mounted and hopes it working out.
As for the DSC just turn it off when you playing with boost or remove the fuse like HPF did on their M3 and see what happens.
BTW, with 390rwtq that all wheel drive is going to be insane either way you look at it. 350rwhp and 350rwtq is fast on a all wheel drive car with stock internals etc...
Wish you the best and looking forward to the more photos once you have the top mount sorted.
Rito
 
#70 · (Edited)
cutting the dsc doesn't work on XI, I'm having software issues after the rwd swap b.c of this. And BMW of NA won't reflash my ecu b.c of legal/vin issues. I'd really like to know more about the abs/dsc problems/solutions you are having/working out. However you have an AT so you are able to control more than with a M/T. Either way epic thread!! epic pics!!
 
#69 ·
Might be a dumb question, but you are gong to cut the manifold around the flange, correct??

Also, do keep in mind with the top mount setup heat will BECOME a problem. You have plug wire, plastic valve cover, etc. there. Many e36 have had problems.
I would definitely ceramic coat everything and buy a turbo shield. i would also wrap those plug wires.
 
#72 ·
no, i'm not cutting the manifold.

manifold is a T4 flange, i've got a t3 to t4 adapter, that doesn't raise it quite enough to clear the valvecover. i ordered a T3 to T3 adapter, one of those ones that adds a wastegate flange between the turbo. i will be using that to space the turbo further up. it should clear then, hopefully. the wastegate flange will not be used on the adapter.

i also got a wastegate angle adapter to move the wastegate out of the way of the ac compressor below.

i will figure something out about the heat. a turbo blanket will def be installed, and the essential wires protected.

also, that is 390 ft/lb at the torque converter, so after going through all the gears/differentials it will be less than that.
 
#71 ·
Looks good... I looked through the pics a couple times and didn't seen any jack stands though. A guy here at work was killed two weeks ago when his jack failed. He had good stuff and a nasty Mustang, but just one of those things. If you were using them and I just didn't see them, then my bad, but still... just sayin.
 
#74 ·
they're the ones with that long tube that goes from the corner of the manifold for the bottom mount to hang the wastegate off, right ?

the manifold i got originally was an ebay piece, and the location of the wastegate port on that thing was not like the technique tuning, so i couldn't just buy the adapter, but i guess if ALL else fails miserably, i'll go that route.
 
#76 ·
topmount is a go





the wastegate barely fits, but it's in. decent amount of space around the turbo for heat insulation.

oil feed is done, going to run return tomorrow, keeping the scavenge pump for now until i decide to blow a hole in the oil pan for gravity return.

going going to start on the downpipe and hot side intercooler piping tomorrow, should be fairly easy to run ic piping hopefully.
 
#77 ·
My man still at it. this thing looking good dude and I am glad we have someone like yourself around. Wish i can see this car in person.
I'll be looking forward to your updates. thanks,

topmount is a go





the wastegate barely fits, but it's in. decent amount of space around the turbo for heat insulation.

oil feed is done, going to run return tomorrow, keeping the scavenge pump for now until i decide to blow a hole in the oil pan for gravity return.

going going to start on the downpipe and hot side intercooler piping tomorrow, should be fairly easy to run ic piping hopefully.
 
Status
Not open for further replies.
You have insufficient privileges to reply here.
Top