Re: 1979 Malibu
Posted: Tue Oct 10, 2023 10:33 pm
So there's been a bunch of happenings/progress that I haven't gotten around to posting about until now.. including the first drives around the block, and (spoiler) an unsuccessful first test-n-tune at Thompson.
First test drive..
Chris and I thought the clunking was related to an un-needed bracket on the 8.8 rear hitting on the Malibu frame (that knocking/rapping sound) and we trimmed that down. The next lap around the block (not in video) and it seemed to be gone.
That led up to taking it out to Kuhnle for a test-n-tune Saturday Sept 30. Steve Jr was super cool and let me borrow his trailer after there were no uhauls available within 20 miles of my house. So, I loaded it up and headed out there on Saturday morning. Unfortunately, I ran into an all-too-familiar issue -- crank signal. That was something I just wasn't really prepared to deal with. This car successfully ran on the dyno and down the track to 6000 rpm with no issues. That day (and probably during the test drives), I was feeling/seeing signal dropout in the datalog. Couldn't really get past 5000-5100 rpm under load. Because of all the issues the prior month dealing with the same thing on the Porsche, I was just kinda mentally defeated. I did make 2 passes, and it was cool to take it down the track. However, my Chevelle would've been ahead of me on both.. (not by a lot). After the 2nd pass I packed up and went home.
Video of the 1st pass, https://files.tiresmoke.org/f/92957b49c ... 8c85/?dl=1 (11MB)
At some point after I got home I took the crank sensor off and it looked like it had made slight contact with the teeth of the trigger wheel at one point, along with a crack in the magnet. I have no idea when that happened.
I put the the new sensor on my bracket and also added one more small washer to the stack to get the sensor centered better on the trigger wheel.
Before: After: Gap set at .034" / .863mm
I also really need to get some heat-wrap on the piping near the turbo. I'm concerned about running with the hood on for any length of time for fear of it (the hood) getting too hot.
-Dave
First test drive..
Chris and I thought the clunking was related to an un-needed bracket on the 8.8 rear hitting on the Malibu frame (that knocking/rapping sound) and we trimmed that down. The next lap around the block (not in video) and it seemed to be gone.
That led up to taking it out to Kuhnle for a test-n-tune Saturday Sept 30. Steve Jr was super cool and let me borrow his trailer after there were no uhauls available within 20 miles of my house. So, I loaded it up and headed out there on Saturday morning. Unfortunately, I ran into an all-too-familiar issue -- crank signal. That was something I just wasn't really prepared to deal with. This car successfully ran on the dyno and down the track to 6000 rpm with no issues. That day (and probably during the test drives), I was feeling/seeing signal dropout in the datalog. Couldn't really get past 5000-5100 rpm under load. Because of all the issues the prior month dealing with the same thing on the Porsche, I was just kinda mentally defeated. I did make 2 passes, and it was cool to take it down the track. However, my Chevelle would've been ahead of me on both.. (not by a lot). After the 2nd pass I packed up and went home.
Video of the 1st pass, https://files.tiresmoke.org/f/92957b49c ... 8c85/?dl=1 (11MB)
At some point after I got home I took the crank sensor off and it looked like it had made slight contact with the teeth of the trigger wheel at one point, along with a crack in the magnet. I have no idea when that happened.
I put the the new sensor on my bracket and also added one more small washer to the stack to get the sensor centered better on the trigger wheel.
Before: After: Gap set at .034" / .863mm
I also really need to get some heat-wrap on the piping near the turbo. I'm concerned about running with the hood on for any length of time for fear of it (the hood) getting too hot.
-Dave