N62 Z3 Part 22: More Reassembly & Pointless Cosmetic Details

Yeesh. I need a bigger DME box

Bought this strut bar for a 4 cylinder Z3 on the off chance it would fit, was very happy (and surprised) that it did. I will need to do something about the CCV hose though. I am thinking I might notch the strut bar

Although not all was good news... in my excitement to attempt a test start, I forgot to install a couple grounds and this happened. I couldn't find the other backup I had so had to order another one

But that did give me some time to tidy up some other things with the car and one of the main things I wanted to tackle was the headers. I really wasn't happy with where the flanges ended up sitting once everything was installed. So I cut them off and ended up routing a new pipe which ran closer to the engine. The flange will be spliced in somewhere on this segment of pipe, with the main consideration being to ensure I can still remove the transmission with the headers in place

The main problem previously was that this flange ended up being too close to the framerail but now the clearance is very nice. I bought some brand new V-bands, I'm sure I'll repurpose the ones I chopped off for some other project in the future


After determining where to put the flange I got to work prepping and then welding the new v-band on

The main goal of the flange placement was to ensure the transmission could be removed without removing the headers and there is ample clearance to do so

I then focused on trying to get the midpipe sections oriented properly. I wanted them to be close to the transmission due to the limited clearance under the car and I also wanted both sides to be flowing straight backwards where they terminated. To accomplish this required cutting the pipes midway through and rotating them to change the output angle

The exhaust is now pointing straight back, parallel with the driveline

Then after repeating the process for the other side

Eventually I will merge these into the X-pipe you can see on the left in the below picture, but at least up until the first test drive I plan on leaving them like this

Getting the header flanges done now means I don't have to remove the engine to finish any exhaust work in the future. I am also hoping the midpipe section I started to build will save me some time when it comes to finishing the rest of the exhaust although I guess time will tell on that one


Next there is one chassis modification left... I over-corrected slightly when I relocated the steering rack and it is now hitting the oil pan very slightly. It had to be re-adjusted again, third time is a charm I suppose. I also welded the top nuts to the subframe to keep them locked in position. This is how it looks finished and with everything reinstalled

I'm kind of killing time at this point in the build... I am waiting on the secondary air system pipes. I've had them dropped off at a fabrication shop for quite awhile at this point and they haven't made much progress, so I've been doing other things such as painting the transmission output flange while waiting for them

I was going for a shadow chrome-esque finish, I think it came out fairly well


I then decided to reinstall the engine to make sure the exhaust was sitting in a good position. Looks good so I will continue to build it out from here while waiting for the SAP pipes. Most of the exhaust will be constructed of new 2.5" mild steel

Because the engine was also reinstalled I plugged everything in for a test start. This is a big milestone I have been *somewhat* avoiding because I get pretty anxious about this kind of stuff especially since last time I did this I fried a DME. I sorted that issue out but in the back of my head something was nagging me saying maybe something else was wrong from the engine rebuild. I'm always a little afraid something will go wrong when that deep in an engine even as extremely careful as I was. Well luckily, today it was smooth as butter. I have a new DME now so re-synced the DME/EWS and went to start it. Cranked, started and idled right away

A few things to sort out and the response was a little lethargic but the MAF wasn't plugged in which I expect was a contributor to that. I later plugged the MAF in, cleared adaptions and throttle was very responsive. The oil was just above the minimum mark which is why the lights came on under load

Now that everything seems good and is ready for a test drive it was time to do final preparations. First step was plugging the SAP ports


This open port was what I needed to plug, this opens into the exhaust so has been a minor exhaust leak

My original plan was to cut the SAP pipes and then weld them shut, so they'd look like below when installed. While I was eventually comfortable aluminum brazing the shift carrier, I was afraid the SAP pipe area would get too hot. The brazing rods melt at 700F and exhaust can get hotter than that. I didn't want to risk the SAP pipe getting so hot the brazing melted out and it "opened" again


An alternative along this way was to use the full length SAP pipe and a blockoff plate. However once I bought those and got them in I realized they were just way too big and cumbersome. I needed another solution

My first thought was to tap a freeze plug in there, and if needed build something I could screw into the back of the engine (where the pipe is) to keep pressure on the plug to keep it from blowing out. I wasn't able to find any freeze plugs the right size so kept thinking


Eventually I ended up tapping the port itself to be able to thread in these exhaust plugs to fill them. Looks like OE if you ask me and doesn't add any extra length out the back of the engine like the other solutions I thought of would

This has something that has been bothering me for almost the whole build and the solution ended up being a lot simpler than I anticipated


Next with the engine out was to construct the midpipe. I did not want to be crawling under the car a million times to test fit, cut, re-test fit, etc pipes a million times. So last time the engine was installed I took some careful measurements of everything and knew where the midpipe needed to go. Below is the finished product, sans a short length out the back

And installed ...pardon my messy shop lol



Just a handful of small things to do before what I hope is the final installation! Notably I'm going to get a heat shield around the fuel filter and the lines in that area, I also need a new dipstick tube O-ring


In the meantime I got the heat shield installed

There was a pretty big pause here where I didn't work on the car for a couple months over the holidays. Once I got back to it I decided to stop being so pedantic about everything and just focus on getting to the first test drive and working out the remaining details later. With that in mind the first order of business was to reinstall the engine

I had to be much more careful this time because while it was out I also installed a new oil pan from Uro. Thankfully that plus an oil change seemed to fix a small leak that had developed. I suspect the oil filter housing was a tad loose... in any case, the new pan also looks a lot nicer!

And the exhaust installed in place without any hassle! The center of gravity of the midpipe seems to be just at the front edge of the resonator towards the X-pipe, so I think I will add some exhaust mounts there

It does hang a little low... I may adjust where it drops under the transmission mount to tuck it up a bit higher. For now though I'm going to add an exhaust mount and move on to the next thing


So while waiting for the shifter carrier to be finished up I ended up not renewing my lease at the shop space. Which meant as of writing this I have about 3 weeks to get the car finished and either drive to my home, or get it towed. I wanted to drive it...


So this is where I am at now. I ditched the dual intake for convenience sake as I had an already fully assembled stock front clip hanging around. I installed it and wired everything up


I also finished the bleeder hose and radiator hoses so assuming it passes a pressure test the cooling system is done. I got the hood back on and aligned. The shift carrier is finished and installed now, so I have shifting. I don't have clutch action yet though - the hardline got caught on the trans and bent a bit and now when I go to install the slave there isn't enough flex. I kind of foresaw this happening tbh. I've thought of a few ways to fix it, I think the easiest which I will do for now will be to remove the slave and run a short length of flexible line between hardline and the slave

Next I got the electric fan finished, I grafted the electric fan from an E53 X5 to a Z3 fan shroud

Next is a little silly cosmetic project. Which followed a big life change for me... I no longer have the shop. I wasn't taking on customer work for awhile so it didn't make sense for me financially to continue the shop. This was the last photo I have of it at the shop before I loaded it on the trailer to take her home

So, the car is at home now sharing garage space with my S54 powered Z3

My M has been calling the swap a poser for having an M badge so had to address that. Ordered these little metal V8 badges and mocked them up

The M badge sits recessed in the trunklid so my goal was to re-shape the recess to fit the V8 badge, so it was like OE

Still not completely finished at this point but gives you an idea of how it will look when finished


I also modified the strut bar to fit properly by notching a hole for CCV hose clearance. DME and Valvetronic control unit are also plugged in and somewhat(?) organized

Although after closer inspection I'm not sure the strut bar will make it to the finished product - it might not fit under the hood - too tall at the strut towers. May try to trim it down. May look for a strut bar that goes rearwards to the firewall. May not do anything about it and just not have a strut bar for the first drive


Then I got the slave bled and worked on the shifter, modified it to get it sitting centered

I also threw on an M bumper I had laying around with shaved corners

Then I got the driveshaft into place

There was one hiccup though... I got everything situated into place then went up top to test the shifter. With the driveshaft in place, the selector rod is hitting the giubo in reverse. D'oh!

After modifying the selector rod to clear the giubo I finally was able to completely bolt in the driveshaft

I took a moment to once again test the shift linkage

And for the first time ever, I gave the installed driveshaft a little spin to see how it felt. It seemed very good with no signs of anything weird

I'm also splitting this into a new post because this is taking, as usual, much much longer than I anticipated

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