Haven’t been online in a while, just busy with life, but trying to get to my rear differential rebuild finally in the next few weeks. I just need to order some Motul fluid…but I do still have AC after swapping back to an OEM unit a few months ago! I haven’t been driving the G37 too much, but will still swap oil pans to my CJM pan at my next oil change in 1-2k miles (prob early summertime at the latest). I keep forgetting how much I have to do, there’s a pile still ready to get installed sadly.

I’ve been kept busy with my BMW F30 328i (N26) which has consumed most of my free garage time lately. It started with a valve cover leak from the crappy plastic factory valve cover, and has gone a little wild from there. I ended up replacing the valve cover entirely with a new aluminum cover and new gaskets, tossed in some new ignition coils, replaced the accessory drive belt and tensioner, did a diff flush, and am about to install braided brake lines on it to finish off my scheduled maintenance. I also had Mr. Saikou fabricate another custom catch can for the N20/N26, which I’m really excited to install in the BMW- I found a generous amount of oil in the crankcase vent tube when I swapped the valve cover, and immediately emailed him to get a setup going for the N20/N26 to mitigate this and prolong the life of the turbo. His new design incorporates a sight glass into the OCC, vs the vertical sight tube previously offered, which will be very convenient. I have to source and fabricate some custom hose connections once it comes in but think I’ve figured how I’ll do it, just waiting to have the can in person to cut a custom carbon fiber bracket for it and get hose lengths needed. Happy to share pics if anyone is curious how it turns out.

Hope anyone who might see this is doing good, safe driving out there.

 

Glad to see you are still around. Hope you're enjoying the BMW. I still do not know why in this day and age we can not get decent valve covers that do not frigging leak. I know it is only a matter of time on my E89 (N54T) before I have to tackle that hassle. Just did the updated PCV, belt, pulleys (damn plastic crap) and other incidental maintenance. I wonder if Mr. Saikou could come up with something for the Zed/4 hmmm...

Again, still glad you are sporting the G and, with summer coming, that AC will be priceless. (Is Hawaii still in the cards?)

 

Goldbug, I'm expecting an awesome review for you on the gears. You're ridiculously detailed, so I bet it will be great.

I don't think there's enough discussion on this forum about short gears. You might want to start a whole new thread on the topic.

GL with the upgrade.

 

Absolutely love our little BMW, it has become a personal favorite and I plan to steal it from my wife soon and make it my DD, lol. We’re planning to buy another BMW for her in the near future (G22 coupe) because we’ve had such a great experience with it, and she wants a coupe while we don’t have kids. It’s been a blast to work on honestly, and I’m excited to slowly upgrade it with a new charge pipe, boost pipe, turbo inlet, 6.5” intercooler, BM3 tune, HKS DV/BOV, and some poly trans and diff mounts (VTT for engine). I’ll snag some Bilstein coilovers for it eventually and swap out the Aodhan wheels to nicer Apex brand 19x9 square. The N26 leaves a ton of room in the engine bay so working on it is a breeze.

I feel your pain though. The valve cover gasket started leaking at about 80k miles on our motor, I was surprised it wasn’t cracked honestly. Definitely consider the Uro Parts aluminum cover if you haven’t already- I was very pleased with the quality and fit of their cover for the N20/N26, and included nice new hardware that uses the same e-torx socket (a plus IMO). Going aluminum vs replacing with another more expensive plastic version was a no-brainer for me, but I respect people who want to stay OEM. It was a 6hr job for me as a first-timer on that motor (breaks not included haha).

Which generation Z4/what motor? He does make a kit for any BMW that uses the 19mm(?) push-lock OEM style connectors, made to work on the E36, E46, and E90. I’m not BMW-savvy enough to know which motor uses what crankcase connectors though, you’ll have to excuse me.

 

I’ll definitely do that, you are absolutely correct. You can find bits and pieces of feedback about the 4.08 and/or Wavetrac, but no one has made a thorough write-up with all the nitty-gritty details some of us really want to know, and I’m happy to help the community. It’s been more of a delay finding someone here in SE Florida I can trust with shimming. I can DIY with a buddy who works on Nissans thankfully (drift car S14 with a built R200), so I’m going to see if he’s up for it first. We just need to find the right shims, and again, not much info out there to help, so I’ll be the guy. Z1 sells the shims online now, so that makes life a lot easier once I figure out what I need.

I plan to get back into building out the G37 a little more soon, so I’ll be sure to make more posts/threads. Still got that freaking Stillen intake mani sitting boxed up also

I’m really hoping Z1 truly took my interest to heart (their response seemed genuine) for a 11-13’ sport front splitter, so I’ve been keeping my eyes out. That is the single biggest thing bugging me about my car atm, and I don’t want to do a non-functional splitter again. Either a front lip just for visuals, or a true frame mounted front splitter. The frame mount seems like a fun endeavor but not a priority if I could find a lip that looked good enough. I’d also like to setup my front bumper for quick-release…more fun down the road.

 

I have the E89 (LCI) with the N54T (3.0L I6, TT) with the 7DCT. It is beyond a blast to drive.

Thank you for the recommendations. I will only be going but so far with this car as my wrenching days are coming to end. I know for longevity some things are needed/ recommended especially to keep the turbos healthy and, of course, upgraded maintenance items and the like. Seems to be a lengthy debate on dual catch cans (for the vacuum and boost sides) with the N54 so, IDK.

I do not wish to muddle your build thread so...
/back to topic

 

I confused myself there and thought the E89 was a sedan (and you had both a sedan and a zed 4). I forgot the chassis codes, and hadn’t looked it up yet, please excuse me. I’m in the same boat trying to prepare our BMW for a long life though. I really should have gotten a catch can years ago for this motor/turbo to prolong it, but it seems healthy enough. I’d assume the boost side OCC would be more beneficial in the long run especially if driving aggressively or ever at track events. Vacuum is just for idle and low throttle, so I’d assume it’s less beneficial per-say, but depends on driving habits. If it’s a commuter that sits and idles a lot then I might tend to think the dual can setup is ideal. This is my first turbocharged motor and BMW so I’m learning as I go, and am by no means an expert.

And hey, we’re talking cars, so as far as I’m concerned we’re on topic! I appreciate the respect, regardless.

 

A shot of Mr. Saikou’s new sight glass for his catch cans, for anyone curious. Gorgeous quality, definitely going to get another set for the G37 eventually.

(This is the OCC for my BMW)

 

I think I’m going to pull the trigger soon on an Autopower U-weld race roll-bar for the G35 coupe and plop it in the G37 coupe. I called them today, super nice guys, just waiting to hear back from one of them regarding measurements. We shall see what the measurements say when I can confirm them, but this would be a great, tried and respected affordable option for roll bars for our coupes. The other options are just too pricey, or not ideal mounting locations. I got quoted $4k for a custom roll bar with paint from someone who builds spec cages. Just too much imo and this isn’t a full blown race car nor am I sponsored or plan to be. Just my fun car.

Side note, I got some new Daytona flat-top 3-ton jack stands for work in the garage at home, and have to say how nice and safe they feel vs standard stands with not-so-great fitting pad adapters. I have a flat rubber adapter for the pinch weld, nothing is going anywhere. They are 1.5 ton (3k lb) rated per stand though, which HF should be more upfront about. 3k per corner is still more than plenty on our cars that weigh under 4k, but it’s not 6k lbs per stand- it’s 6k total for the pair when both are used.

 

Sent some ECUTek log files to Seb to take a look at, and survey says…he found some knock correction I hadn’t noticed. I’m really hoping it’s a bad tank of 93 octane gas from Wawa (which I avoid for this exact worry). Didn’t have time to drive to my usual stations (Shell and Sunoco) and regret it. On the BMW forums, some of the FL members have said how bad the gas is here, and that they actually run a 91 octane map with 93 octane gas here, and have better results. I’m curious to see what Seb has to say about this, pending his response I might grab another set of logs with my current 93 octane tank using the 91 octane map he made.

I also didn’t think about it at first but my Z1 rear differential brace does rattle against the HKS exhaust. Wondering if it could be correcting due to a false positive caused by that…The brace clears the exhaust by about 2-3mm but obviously exhausts move and sway a little under load etc., so it rattles occasionally, mainly at lower RPMs on cold start. I probably can’t hear it rattling at higher revs. So I’ll remove it to be safe for now. Seb might end up laughing about this one. Let’s hope we do, otherwise it might be the end of line for this motor soon enough.

If this motor does die, I’ll pull it and drop in an LS(3), for real. It won’t happen overnight, and my car will sit for a few months, but I’ll do it.

 

5.6 from a Titan...

 

I’d give a finger up for a NISMO built VK56, VK50, or VK45…I’m sure there might be one laying around somewhere here in Florida. I like the idea of the VK50 or VK45 more due to their smaller size.

Edit——screw it, I’m going to grab a VK45 in the next year and build it out to swap. It seems like the easiest swap out there as a lot bolts to factory locations and requires minimal modifications. I will have new engine mount locations fab’d and welded in, as I want it to sit further back and lower and have read it’s possible to do so in the G35. I’ll grab a mint used VK45 and build it out to match the NISMO VK45. That will be more than enough power for this car, I just want 400+ lb ft of torque in the end.

I’m getting older and realizing how true the saying “time is money” really is. So I’m doing things within reason on this car. Still building it into a dual purpose car with top-notch parts, but I’m not trying to make any magazine covers. Just want to enjoy it and the build out. It’s the journey that’s fun to me. Exactly why some of us don’t go buy already modified cars. To each their own.

 

For anyone curious, I removed my Z1 rear differential brace that was making contact with my HKS exhaust. I’ve been keeping a close eye on my ECUTek dash, but so far, no signs of ignition correction It looks like that brace was really causing my ignition timing issues. I still have to data log again for Seb today or tomorrow but I think my knock correction issues were caused by a false positive.

So for anyone else with an exhaust rattle, don’t shrug it off. It can legitimately trigger your knock sensor and pull timing unnecessarily.

 

Wow that's great detective work there! (no sarcasm)

 

Sadly I got my hopes up too soon. Exhaust rattles can still cause false positives with knock sensors though, regardless of my issues!

I had no signs of knock correction for almost a week after removing the brace and started to feel confident that it was the brace, but unfortunately yesterday I took my car for a drive and it pulled timing -3 degrees, and I felt power loss. It did eventually recover to 0 degrees and stayed there, but still wasn’t a great sign. I’ll have to do some more detective work now to see if it’s bad fuel, a bad injector, or if it’s something worse I’d see in a compression test. It’s intermittent so maybe (hopefully) it’s just bad fuel like Seb first hypothesized. I need to replace my injectors anyways at my car’s age and mileage, if it ends up being a bad injector. In which case I’d drop in 1050’s.

Worst case scenario: VK or LS3 engine swap time, not sure if I’d rebuild the VQ37