29 Mar The Burning Bush(ings)
It’s Friday, so let’s play with some fire. If you’re wondering how those two things typically connect…they don’t.
Either way, you may remember the E46 M3 we’ve been featuring rather prominently this week. First, we did a three-part DIY to help anybody that’s looking to drop their own subframe and install some reinforcement plates. If your vehicle’s getting up there in terms of mileage, we strongly recommend you do that before it results in serious body work. Anywho, while the subframe was dropped, the customer requested that we install some Powerflex polyurethane bushings for him. In order to minimize additional accrued labor, it’s smart to get these bad boys slapped in when your subframe is already dropped for a different reason, such as reinforcement plate installation. Two birds, one stone, so to speak.
So we set about removing the parts from the subframe in preparation for the bushing removal.
Seeing as how the old bushings are, well, old, we need to pursue a slightly atypical method for their removal. That method? Fire, brought to you by way of an oxygen-acetylene torch. Now, if you pursue this method, you must ENSURE that you have proper ventilation in place. Old rubber does not produce a pleasant, non-toxic odor; as a matter of fact, it’s completely the opposite. We had fans going and every single door open in the fabrication garage, and it was fine, but we also know that not everybody has their own shop space to utilize. So don’t do this in an enclosed garage or your basement or something like that.
If you did it right, your bushings should come out with nothing more than some soot on the subframe. If you did it wrong, you’re out either a subframe or a garage/house. Once the bushings were removed, we spent time cleaning the inside of the bushing housings on the subframe to ensure a complete and correct connection between the two parts.
After a little bit of elbow grease, the bushings should fit right in place. They’re all very distinctly sized, so it’s not like you’ll end up putting your differential bushing in the subframe housing and vice-versa. Although if you manage to squeeze that giant yellow bushing in the tiny slot on the differential, color us impressed.
Once the bushings were in place, we realized that there’s no point in putting a dirty ol’ subframe and differential back in the car without a proper power-washing to help remove some of the grimy nastiness that’s caked itself onto the steel over the course of years of operation.
And with that, it’s time to slap the subframe back in place. In the picture below, you have new mated up to new — fancy new Powerflex subframe bushings connected to some slick new subframe mounts with a coat o’ paint to seal everything up. Mission accomplished!
Well, it’s actually not accomplished just yet! The owner, now with a car that’s as tight as can be, has decided to add a few more ponies under the hood by way of a Fluid MotorUnion custom ECU tune. We’ve got some video of its most recent dyno runs, so we’ll bring that to you next week, along with other goings on in service and fabrication! Have a great Easter weekend, and enjoy the nice weather!