16/01/2022
A very picture-heavy post.
I felt it was time to do an in-depth detail on this. It's a car that I'm actually quite grateful for, and an owner in many respects.
The owner has effectively given me the contents of his wallet a few times in the pursuit of something a bit different. He's owned the car for years, and now, it's getting close to its final form.
The first visit was for a set of camshafts, way back in the dim and distant Year Of Our Lord Two Thousand And Seventeen.
Since then, I've advised on most aspects of it, and in 2020, the owner lost his marbles and just gave me the car for a large part of 2020/2021. After all; what else did we have that was better to do..?
Phase 1 saw a full rear end strip down, inspection for rust/rear subframe cracks, welding in a reinforcement plate kit from Redish Motorsport, and a rebuild with some sorted out parts. Powerflex rear subframe bushes were a noteworthy inclusion. At the same time, I just happened to have a 6 speed Getrag from an E36 M3 3.2 sat around, and whilst carrying out some other work in the engine area, I checked to see if it fitted... thus creating a 6-speed 330i Touring that shouldn't technically exist. It was done with entirely factory parts other than the propshaft spacer. We could have gone for the later 330's ZF 6 speed, but they are a sod to find, and it's far easier to get uprated clutches/flywheels for these (in fact, he already had one, which was a huge deciding factor).
Phase 2 saw another minor innovation. Time to upgrade from the Alpina B3 system that was a bit past it... so we went for S54 exhaust manifolds. They don't fit, unless you have access to a tame TIG welder. A weekend of poking and prodding, and it was done.
Phase 3 saw the most intensive activity yet- the owner checked compression and it was down on psi on cylinder 1. M54s are notorious for gumming up their piston rings, and this was the suspected cause. A stripdown found this was definitely the case, and so it was time to rebuild... with fresh ARP everything, fully balanced internals, an Alpina 3.3 crank pulley, the aforementioned cams/S54 exhaust setup, a fully rebuilt head with Supertech stem seals and freshly lapped valves, and some other little innovations. The S50/S54 oil filter housing fitted, with some minor adaptations for the power steering pump, and an oil distribution block was designed by the owner and implemented by a local machine shop to allow an extra port for an aftermarket sensor, as well as putting a port back in the system for oil temperature that usually lives on an M54 oil filter housing. It went to dyno and made 261bhp/333Nm- not bad for an engine with "just" cams and an exhaust manifold/system setup.
The tuner remarked that the cams would benefit from being a tad smaller on the exhaust side if left naturally aspirated. The exhaust cam will be staying as it is. He also added that the S54 exhaust system would definitely only really add huge benefits if a supercharger or turbocharger was added...
Phase 4 to come. I'll leave it to you to work out what's next, if you made it this far.
