Black & Tan 332iT

[Bry5on]

A few things:
1) Euro Mullet tune v26 seems to be on the money now. I'm happy with cold start operation and a couple days in it still seems to be butter smooth everywhere in the rev band. More seat time to come, but hopefully this is the last rev

2) Tonight's realization after modeling the e46 rear suspension: The e46 suspension is just a semi-trailing arm suspension that accommodates camber and toe adjustments. It's really just an evolution of the e30 and prior designs. Suspension behavior is much more in line with a semi trailing arm than a multi-link suspension due to the placement of the members. Can't believe I hadn't realized this until now, duh.

Looking from the bottom of the car, the lower dashed line in this picture depicts the axis of rotation of the 'trailing arm' as the instant center is basically stationary throughout suspension travel:


3) The hubs are slightly rearward of the diff output flanges, about 20-30mm. This is probably to keep from passing the CV joint through its center axis position if I had to guess.

4) There is quite a lot of anti-squat in the e46, but we already knew this. Wheel hop!

[Bry5on]

awesome thread and nice daily that you are building. what kind of program did you used to compare the binaries? it's time consuming with tuner pro and loading different xdfs all the time.

Oh boy. Tuner pro, excel, a bit of Python. For logs, megalogviewer, datazap.me, excel. And lots of time, it’s definitely time consuming.

[Zekarus]

awesome thread and nice daily that you are building. what kind of program did you used to compare the binaries? it's time consuming with tuner pro and loading different xdfs all the time.

[D-O]

Well, I picked up myself one of these 3D scanners finally, so today was time to get my first scan and model created. The rear suspension.


Here's a link to the results, this is a scan at factory ride height, suspension compressed. You can peruse around yourself, take measurements, etc: https://s.digital3dcloud.com/space/0...0155&sharePwd=


I wanted the geometry and locations of the diff/axles for the next project, a proper multi-link rear suspension. Current plan, which looks pretty doable, is to build a custom subframe with e39 rear suspension pickup points. Then bolt in a full e39 rear suspension with some e60 wheel bearings/hubs and I should be able to just bolt my wheels back on and go. Piece of cake.

You will undoubtedly make it look like a piece of cake.

Really impressive build. Thanks for sharing.

[Bry5on]

Well, I picked up myself one of these 3D scanners finally, so today was time to get my first scan and model created. The rear suspension.


Here's a link to the results, this is a scan at factory ride height, suspension compressed. You can peruse around yourself, take measurements, etc: https://s.digital3dcloud.com/space/0...0155&sharePwd=


I wanted the geometry and locations of the diff/axles for the next project, a proper multi-link rear suspension. Current plan, which looks pretty doable, is to build a custom subframe with e39 rear suspension pickup points. Then bolt in a full e39 rear suspension with some e60 wheel bearings/hubs and I should be able to just bolt my wheels back on and go. Piece of cake.

[Bry5on]

Now that the weather is cold again, I’m using the heated seats a couple times a day. And once again noticing the aftermarket-ness of the elements that were stitched in when the leather was done.

Two things bother me:
1) The stock seats heat up super quick, these take forever to get to temp
2) They don’t work when the seats are cold! Kinda defeats the purpose.

So I decided to take matters into my own hands. I purchased e39 heated seat elements a while back and decided I was going to reverse engineer the heated seat elements to make my own. Well, I took all the measurements and ended up deciding to just modify the e39 elements as they were a pretty close size match for what I wanted.

Some specs (measurements are close enough, used my fluke DMM):
AMX elements, 4.6 ohm total impedance. 9.2 ohm seat bottom and 8.1 ohm seat back
e39 elements, 1.2 ohm total impedance. 2 ohm for the bottom and 2 ohm for the back

The factory elements are rather simple, just a stranded plated copper 28-29AWG wire with a very thin, likely teflon, jacket. The seat bottom has a thermocouple that I didn’t bother measuring, but that’s it. The back and bottom heating elements are wired in parallel.

The measurements explain the slow heating story, the 4x impedance means that they heat with 1/4 the power (P=V^2/R in this case). So the math agrees with the butt.

The seat bottom mostly fit without major modification, but the back needed a bit of extra work. What started as a rectangular piece went through a transformation to an element that supports a nice warm hug. Some photos below.

Overall, works like stock now. Happy with this.

[0-60motorsports]

CSL Cams and Valves, Only thing missing from my car LOL

[Bry5on]

Finally tackled the oil pan gasket. Fun job!



Also while I was at it, I replaced the AC condenser, as a last ditch effort at helping the car cool better on steep uphills on hot days. If this doesn’t do it, the logical last thing to check would be the head gasket, but there’s no lost coolant over tens of thousands of miles, so I’m a bit stumped.



Also in the interest of getting the cooling system in line. The M3 belly pan has a plastic support bonded to its top side. This bonded piece supports the bottom of the radiator duct to prevent it from blowing air under the oil cooler. Well, the non-m belly pan sits about 3/4” too low to support this, so I blocked it up with foam to achieve the same effect as the M3. Anyone with a swap car should do the same!


And last, swung by a friend’s place and found two very clean LSB CSL replicas there. One in the middle of getting CSL cams and valves. Nice cars.

[George Hill]

Ah so let's say if you're pulling the front seats from a desirable complete interior, someone is well within their rights to swoop by and snag the rear?

The car is yours, the etiquette IMO is to ask the person pulling parts what they are getting and if its not something you want then tell them what you want and if you aren't in their way go ahead and pull them with their permission.

[usdmej]

First come, first served.

Ah so let's say if you're pulling the front seats from a desirable complete interior, someone is well within their rights to swoop by and snag the rear?

[George Hill]

curious what the "dibs" etiquette is for something like this at the junkyard?

First come, first served.

[usdmej]

And to anchor on that contrast, here's a slicktop orient blue wagon with manual, heated, sport natural brown interior at the Oakland junk yard:

curious what the "dibs" etiquette is for something like this at the junkyard? i've only pulled smaller parts but have always wondered what would happen if multiple people were hovering over a desirable spec vehicle

[Bry5on]

I'm getting the parts together for this mod. Spherical Rtabs are to jarring. Did you go with turner limiters? If so what's the point of the screws it comes with?


Sent from my iPhone using Tapatalk Pro

I think mine were made from delrin, no screws. Purchased from ecstuning.com. Enjoy!

[Grke46m3]

Well gents, I've finally got it. This morning, I did e89 Z4 RTABs with outer side limiters along with the 1mm larger CSL rear sway bar. Man, this is the hot ticket. I've finally got it right! That little bit of extra rear roll stiffness made all the difference. The car is more neutral and playful in corners now, super neutral and fast if you're smooth, but it'll still understeer on entry and oversteer on exit if you're ham fisted/footed. Really nice to have that little bit of extra roll stiffness for the square tires on stock M3 springs, and it still has juuust a touch of understeer balance. The math says this should be keeping me off the bump stops and I'm inclined to agree. Just perfect, very happy over here.

What can I say about the Z4 RTABs? Well to my taste, they're 75% of the precision of solid bushings, with the same NVH as stock bushings. No more rear end wiggling on throttle, but no NVH penalty. Really fantastic trade off as the rear is very well controlled again. The reason to go with Z4 bushings is all about how much rubber they have to press against the carrier (or limiter in my case). Otherwise they're the same internal stiffness and geometry as stock e46 M3.

The bushings that came out of my car are near as new M3 parts, lemfoerder if memory serves, and had just a few thousand miles on them. You can see below that there's plenty of evidence of the bushings toeing out all the way to the edge of the carrier. This calculates To almost a full degree of toe out. Hugely destabilizing! Again, these are new bushings! A solution to the rear end wiggling under throttle was required.


I used limiters from ECS for the outside of the Z4 bushings (half of the kit of four), which have a much bigger rubber lip on the outer side (toe out under throttle side). To fit the limiters, there's just a minor trimming operation needed to make the limiter sit totally flush with the bushing. They then get installed all the way until the flanges touch the rear trailing arm. They get bottomed out, which looks a bit off, because the metal is not centered in the bushing like the e46 style, but this will place the bushing in the correct location.
By only installing outer limiters, this mitigates toe out under throttle while maintaining the factory designed toe in under braking for braking stability. I really wanted to keep that feature, and I'm happy to report that the results are great.
Other than that, install is totally normal. Make sure you set your toe correctly after or have the car realigned. Here are a bunch of pictures that might come in handy if you're doing this yourself, including my method for keeping my alignment the same before/after.


And a few shots of the CSL rear bar going in, along with the final installed washer fluid reservoir for good measure. Happy Saturday.

I'm getting the parts together for this mod. Spherical Rtabs are to jarring. Did you go with turner limiters? If so what's the point of the screws it comes with?


Sent from my iPhone using Tapatalk Pro

[Bry5on]

Not much to write home about - thanks to some probing from karter16 I decided to get into the hardest part of the mullet tune to iterate on - cold start operation. We're on mullet v22 now for the euro tune and cold starting is pretty smooth operator from my last test, which is merely a single data point. It was previously much better than the default CSL tune, but not as smooth as a factory regular M3. More testing needed before confirmation that it's licked.

I've been working on the jag EV and man that thing makes me appreciate how easy the e46 is to work on. I replaced the coolant based heater core with a PTC resistor based core that I fabbed. I swear that car is built around the damn heater core and that they put it together with combo wrenches 1/12 of a turn at a time.

But back to the e46, I bit the bullet and ordered a new steering wheel - feels nice!