Well, it's cold, windy, snowing and generally all around miserable here today, so I'm thinking it's the perfect day to post the latest update I promised this weekend.
With the successful testing and trial run of finally supporting the car with its own air source the week before, it's now time to focus on the second stage of completing the air management install.
Namely the ride height sensors.
As I mentioned before, these are basically potentiometers with an arm that connects to a heim jointed link that you attach to a suspension component at each corner.
As the suspension cycles through its travel, the potentiometer "reads" where exactly the suspension is on that corner in its range of movement, and relays that information back to the air management ECM. The ECM then tells the valves to either add or subtract air from the air spring on that corner to effectively level the car. Pretty simple stuff.
The first step to begin the install was to put the car up on stands and remove the wheels and tires.
With that done, I suspected I may have had some interference issues on the rear suspension that I wasn't able to see with the car on the ground, so I removed the passenger's side rear caliper, caliper bracket, and rotor.
After some sleuthing and careful measuring, I was correct and found the issue. Somehow and somewhere in the process of measuring, marking, cutting and welding the housing ends back on when the 12 bolt rear end was narrowed, the passenger's side axel tube has ended up a 1/4" shorter than the driver's side.
Now normally a 1/4" isn't necessarily a big deal in the grand scheme of things, but in my particular case, it places the Wilwood rear disc brake assembly (and the wheel and tire) very close to the framerail.
The bracket for the emergency brake cable attachment is the component on the brake assembly that sits closest to the framerail:
While the bracket cleared the framerail at ride height and above, when the car was aired down, the E-brake bracket rubs the frame as evidenced by this witness mark:
Now, if I was Chip Foose, or Troy Trepanier, or simply made of money and time, I wouldn't hesitate to yank the rearend out and take it in somewheres to have the 1/4" discrepancy issue corrected.
However.
(Lol)
I am none of those things, and at this point in time I'm not prepared to reinvent the wheel (pardon the pun), so I will find a way to buy some clearance for the bracket to the frame, and will likely run a 1/4" spacer between the rotor and wheel to properly position the wheel in the wheelwell. That will be the most cost effective way to work around the issue. At least for now.
Not totally prepared to deal with this new found problem at this point, I simply unbolted and removed the E-brake bracket for now, and got on with things.
The next thing I wanted to check now that I had nothing else binding or rubbing, was max upwards travel of the rearend with no wheels on it. Here's where it sits before it started to raise the back of the car off the stands:
There's about a 1/2" of clearance between the top of the axel tube and the bottom of the framerails in these pics, but I know for a fact that the frame will actually contact and sit on the axel tube with the weight of the car on the wheels. I saw this firsthand when the car was aired down and still on its wheels. No biggie, but I was glad I was aware of this before I started installing the ride height sensors, as it all matters.
Continuing to work on the passenger's side of the car, I found the optimal location to mount the sensor was on the front side of the rear crossmember. This positioned the linkage to line up almost dead center on the lower control arm, which is ideal to get the most accurate reading for the ECM.
Problem was, I had already initially allocated that particular area of real estate for bulkhead connectors for my fuel supply and return lines to pass through.
The holes were already drilled, and the bulkhead connectors were also already installed, but thankfully the stainless hardlines were not yet done or in place. I removed the innermost bulkhead connector, and am confident I can just relocate it above the outermost one. I'll end up with an "up and down" arrangement to them instead of "side by side". That should still work just fine.
Taking my time, and carefully measuring, test fitting, and trying to consider all possibilities, I eventually ended up with the sensor, arm, and linkage mounted to the frame and lower control arm as such:
You can clearly see the hole from where I had to remove the one bulkhead connector. Also visible in that pic are the two holes where I had initially tried to mount the sensor; that position wouldn't work as it required the linkage to mount in the wrong hole on the arm for the amount of travel it has. (Yeah, that matters too!)
Mounting the linkage to the lower control arm was a simple process, the location on the control arm was determined with a plumb bob positioned at the proper hole on the arm, then a through hole was drilled through the control arm and the supplied stand-off was mounted. Once that was done, measurements were taken to determine the linkage length. The linkage was cut, reassembled, and then attached.
With these couple interference issues, and trial and error experiments of component locations, you can now see why I've held off so long on removing and powder coating the frame. Having to move things around and weld up holes etc after everythings been powder coated would REALLY suck.
Anyways, with the sensor now mounted, the suspension was cycled through its travel, I took pics of it all the way up, mid-way, and all the way down.
The above pic is with the arm "all the way up" (aired down), here is "mid-way"...
...and all the way down (aired up):
Continued... >>>
