12 Mar US Spec Alpina B5 Tribute Build Update
Our US Spec Alpina B5 Tribute car is progressing towards completion! This week we wanted to share some of the interesting obstacles we have come across, as well as some that are still yet to come.
The first thing is the radiator support in the 545i. It helps keep the radiator and fan in place, and it also houses the hood latch and release mechanism. However the Alpina comes with a massive front mount air to air intercooler, which needed to be mounted alongside the radiator. This meant we could not use the piece of either car. However luckily our fabrication department is skilled in working metal, and we were able to modify the 545i support to house the Alpina intercooler, and still keep the hood secured.
We also installed the custom long tube headers, which is going to aid in creating the sound alongside our full custom exhaust, as well as unleash this supercharged engines full potential for power.
However, fitting long tube headers in the cramped engine bay provided another issue of clearing the heavy-duty Alpina engine mounts. Our fabrication team saved the day again with a clean and precise modification for better fitment.
We found that in the E60 the supercharged engine fits a bit tighter to the hood than we were comfortable. We looked into modifying the mounts, but with the geometry needed to lower it the small amount we desired, it was easier to drop the subframe 7mm with specialty built plates.
Again getting E60 Alpina Specific reservoirs and the mounting hardware is very tricky, and the catalogs are a bit unclear if they are actually a different part or the same part that comes in a 545 with an added mount. So to keep the build from getting nickel and dimed out of existence, we recycled what we could with clean mounting being the only rule. New lines and mounts were called for but we still have to figure out the power steering cooler, so we’re not done yet!
We also performed one of our underside cleaning services to the vehicle. Our goal is to get this car as close to “new” as possible, and hopefully keep it that way. So we are preparing the underside for a special treatment that will keep the vehicle from corroding for years to come!
The driveshaft is hugely expensive in the B5, so we are going to be weighing the costs of a custom performance-oriented one, vs using the spec version. If we can get something better for less money than OEM, then we have all the reasons to do so. But no cutting corners, we want smooth operation and we won’t compromise with any driveshaft vibrations.
To be blunt, the wiring needed is an absolute nightmare. The only thing we have going for us is that these cars do communicate with the same modules in the B5, however, getting our hands on a B5-specific diagram is tricky. Luckily we had a “fan” reach out to us and let us know that we are doing a dream build of his. He is the wizard over at Crazy DIY Engineer and we were blown away with how much info he has compiled on how to complete this very type of build. He also does some incredible supercharger modifications that we may just be using to make this one of the most powerful supercharged Alpina N62 ever. So far we’ve got the engine and trans to communicate and we can crank the vehicle over, but we will need to work on the EWS immobilizer system and code the car to think it’s an actual B5, so we are looking forward to our collaboration. Definitely check out his site, and hit him up for any BMW or Alpina needs!