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TheSilverBuick's 1977 Skylark

Discussion in 'The "X" bodies' started by TheSilverBuick, Jul 5, 2010.

  1. wormwood

    wormwood Dare to be different

    haha.... thats a lot of scraping
     
  2. Aaron65

    Aaron65 Well-Known Member

    Every once in a while I'll do that too, and then I'll realize that I never sell any cars! :)
     
  3. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Did some general maintenance to the Skylark today. I knew the fan clutch was on the way out during Drag Week last year when the coolant temp climbed to something like 210F in stop and go traffic when it wasn't even that hot out (compared to ~115+F in Vegas without issues). I tried to get a warranty swap on it at two different Autozones but they seemed to have lost my warranty info on it. Which is odd because I did a warranty swap on it in 2009 or 2010 when I went to Arizona for the Car Craft Anti-Tour and that one seized up on me. Anyways going into winter I didn't worry too much about it but last week it started to squeak. It didn't have any wobble or play in it, but spinning it with my hand generated a definite chirp. I don't need to lose a radiator so I got a new one from Autozone.

    Autozone seems to have changed suppliers and I have to say I like the look of the new design. Even stamped "Made in USA" for a bonus. The "broken" fan clutch had little resistance to while spinning, even when hot. I can definitely feel the air being pulled from in front of the car again with the new one.
    [​IMG]

    I guess I had never noticed how small the fan on my Skylark is, five blades with relatively short blades. I've never had a cooling issue with it, such as stop and go traffic in Las Vegas at 115+F, etc. but I do have a 7-blade fan on hand... I ended up staying with the 5-blade because there was a slight interference with the mounting tabs on the new clutch and the 7-blade fan. A quick filing on two spots would cover it, but figured if the 5-blade fan has always worked, it'll likely continue to work.
    [​IMG]



    I also messed with some of the launch control and traction control settings. It sounds a bit cleaner now on the 2-step and I still need to try the traction control settings. I have the traction control settings set to a "perfect run" so it starts a timer after the clutch is lifted and the wheel speed shouldn't exceed certain amounts by certain time, because if it is it is likely due to tire slip. I've calibrated it to my best runs to date and then added a few mph to leave room for improvements.
     
  4. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Thought I'd take some time today to install a hall sensor on the front right wheel to hopefully help me launch the car off the line. The premise is I have a vehicle speed sensor on the transmission letting the Mega Squirt know how fast the rear wheels are turning, and by adding a wheel speed sensor to one of the "un-powered" front wheels the Mega Squirt can compare the two and if the rear wheels are turning faster than the fronts by a programmed amount over a programmed period of time, then it starts pulling timing by programmed amounts. Pulling timing (to as low as 0) effectively kills the horsepower production of the engine, but it'll pull it and give it back as fast as needed to keep the two wheels spinning at nearly the same rate. Basically it'll allow a ~5-10% slip differential so the rear wheels can be turning slightly faster than the fronts to keep acceleration going.

    Many folks have been having luck running the sensor in the brake backing plate or on a bracket and reading the backside of the wheel studs, but it looked like to me the wheel studs on my car don't stick out far enough to get a reliable signal (I didn't actually try..). But I did notice there was a casted lug between each stud, and I checked another rotor I have on the shelf and it had the same casting, so hopefully it's a reliable feature to use if I change rotors down the road. What I needed to do though is bend the backing plate a bit to angle for the lug. That was simple enough just used a cut off wheel to make a tabbed section, bent it, then put a couple spot welds at the joint to stiffen it back up. Drilled a hole in the tab and welded one of the sensor nuts to the tab so the sensor threads in and the second nut becomes a jam nut.
    [​IMG]

    A while ago I started getting away from using the corrugated wire covering, but figured this is a good place to use it to protect the wires. I trimmed out a small plate to hole the wiring in place and used the extra threads from one of the bolts on the ball joint to secure it.
    [​IMG]


    Here is a short video of me testing the sensor before finishing the wiring up.
    [video=youtube;GvIFuRjDqE4]https://www.youtube.com/watch?v=GvIFuRjDqE4[/video]
     
  5. SteeveeDee

    SteeveeDee Orange Acres

    Keep it up! Pretty soon you will have a completely automated launch, with a 0.000 light, every time. Don't think for a second that I haven't thought about this. Perfect light, lifts the throttle just enough if you start to lose it. Perfect bracket car.
     
  6. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    With a manual transmission it'll never be a perfect bracket car, nor does this effect on how well the light is cut. It can however keep you from running over a certain rate, so if the car can run fairly consistent 11.50's, you could set a perfect run setup to dial in 11.70's and probably get that dang near every time. Again, the manual transmission is going to negate most of that the way I shift. I'm simply looking to be able to get my sixty foot down from 1.9 to a very hopeful 1.6x, and get me a mid to high 11 time slip. Also to launch the car much more consistently off a 2-step. For far higher horsepower cars it's handy to have incase it starts to break traction mid-track too.


    Seems to be consistent with the transmission sensor. It drops out when I hit bumps in the road or slow down abruptly, so need to figure out if it's my wiring (always suspect!), the bracket is wobbly, the sensor clearance, or a filtering setting. I have the traction control currently turned off and did a test of spinning up the rear wheels on the dirt road coming into work just to watch the difference. The smaller number is the front wheel.
    [​IMG]
     
    Last edited: May 17, 2016
  7. SteeveeDee

    SteeveeDee Orange Acres

    Yeah, I was thinking automatic transmission. Another sensor could be used to watch the tree and use the scroll down time to "know" when to release the line-lock if used, and to hit the loud pedal. You'd have to figure out if each tree has different timing. You could play with it a little and cut a near perfect light almost every time. Just leave a few milliseconds in the timing for errors- avoiding red lights that way. I know some Braniacs that would be able to get that pretty close. I'm not conversant with the new stuff. I was just a FORTRAN number cruncher in a previous life, from before they added the "C" extensions.
     
  8. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I know people that can do exactly that. One guy I knew programmed a white light detector to watch a small section of a tv screen and when that part of the screen turned white it commanded a lego built robot thing to press a button on his gaming controller to automate some routine he wanted in the game. Basically a lightning fast trigger. I'm sure it's wholly possible to put a green light filter on a car tied to a transbrake release. Just have a button set up so it doesn't accidently pre-launch, so activate it when the double bulbs light up, and as soon as it registers a green light wait the specified time (aka .500) and release the transbrake. I bet a Raspberry Pi could do this with some python scripting.... A 4L60e/65e/80e transmission would shift at precisely the right time, every time. And like I said, the Mega Squirt can be programmed with the "perfect" run in mind so with a smidge of sandbagging it could automatically pull and add power via ignition timing. Just keep the loud petal down. So what way is the quickest way to become the most hated man in racing?? :pp The traction stuff is all the things the "no-prep" folks are using these days to stay at the top. Apparently a ton of power can be killed off running 0 of timing for a couple of crankshaft rotations, and then given right back with max HP timing, all within a few milliseconds.
     
  9. SteeveeDee

    SteeveeDee Orange Acres

    Most hated man in racing. I like that. I guess you could mix it up a little and cut a .040 once in a while, just to seem "honest". :laugh: And the 0 of timing for a couple of crankshaft rotations would be a ton better than lifting off the throttle. If I ever go racing, and my vehicle pulls up to the light looking like some sort of cyborg, you will know what is up. Sandbagging would be so cake, too!
     
  10. TheSilverBuick

    TheSilverBuick In the Middle of No Where


    I think I found the issue. I had one wire pull out of a connector, and another one that didn't take much to make it the same. Tomorrow I find out if I did a better job this time.
     
  11. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    The spark and slip values aren't really tuned, they are approximations of what I expect. The top left panel is my VSS calibrations, the gear detection works perfectly. The bottom left panel is the traction control reactions. I am not showing the boost options, but you can mess with fuel, cut spark, or as I have it there retard the spark based on how long slip is happening. The longer traction is lost the more timing it pulls from what the spark table is commanding. I have it currently pulling up to 25 of timing, from my base of 34. The two panels on the top right just show two of the four options available with traction control. %Slip is pretty straight forward, the perfect run is based on mph after launch, basically won't allow wheel speeds over the programmed amount until enough time has passed. The other option is on RPM instead of VSS. Then "Switched Input" if you have an external traction control box to tell the Mega Squirt slip is happening. The bottom right panel is the MPH versus time panel for the perfect run. I have it programmed to 11.6 @ 118mph. With some datalogs and time slips of good runs this line can be calibrated pretty well.
    [​IMG]
     
  12. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Finally turned the traction control on, with the above settings, for some testing. No significant speed testing but tried five or six burnouts and datalogged two of them. It's a weird feeling, it's not missing like a rev limiter cutting spark but you can certainly feel the power being pulled down, softly. I datalogged the most extreme case which is sitting on the 2-step limiter and just dumping the clutch, which usually sends the tires up in smoke and the rpm's to the moon. One caveat to this though, I didn't try laying the pedal to the floor due to where I was driving, but in a normal circumstance, that throttle position should of produced a much much longer burnout.

    I annotated the datalog a bit. I have a minimum threshold of 5mph set so it won't do anything until the car is over 5mph, and once there traction has to be over 5% different (check), and it took 0.21 seconds after the first reading above 5mph for the timing to be pulled down to 11.5. I have just some guesstimate numbers plugged in, so I'll probably pull the timing down faster and lower. I have some noise in the rear wheel speed sensor when I'm on the 2-step, so until I cure that I can't really lower the 5mph minimum threshold. Overall, I'm glad that it's doing SOMETHING and can work from that baseline. It was just under 0.4 seconds between the rear tires spinning and the front tire registering speed, then another 0.21 seconds before the traction control kicked in, and ignition timing was reduced for 1.45 seconds.
    [​IMG]
     
  13. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Went out and did another couple tests, this time a bit more aggressive on the throttle to highlight what its doing. I let it pull a lot more timing, but I didn't change the reaction time aggressiveness of it. What it shows a lot more clearly this time is me pushing the throttle down more, but the rpm's are falling anyways as the traction control as pulled timing down around 5 to kill off the horsepower. Then when the wheel speed is in the acceptable 5% difference range it gives the timing back, which accelerated the car and I lifted for a second, then put the throttle back down, causing it to break traction again and re-activate the traction control measures.

    By the numbers, 0.38 seconds between the rear wheels spinning and the first movement of the front wheels, 0.207 seconds of front wheel movement before timing get's pulled down, timing is reduced for 1.257 seconds before front and rear wheel speeds are within 5% of each other.

    More fine tuning to be done, but it looks like if I don't just dump the clutch off the 2-step (which I haven't been at the track) and can get the car rolling just a bit before putting the pedal down, it should do what it's supposed to and let the car accelerate while still allowing an acceptable amount of slip off the line (currently set at 5%).

    [​IMG]
     
  14. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I did a short test run out on an empty road outside of town on the way to work. Instead of dumping the clutch of the 2-step limiter I started with getting the car rolling a bit before putting the gas pedal down and it seemed to work pretty well. Ran it up to 5800rpm in first at 85% throttle and progressively less in each gear afterwards. You can see a few places in 1st gear where traction started slipping again but it doesn't pull as much timing because the slip percentage isn't as drastic as it is off the line, and again going into 2nd gear. I think I'll raise the acceptable slip percentage up to 10%.

    I have the "Flat-shift" option turned on, where I shouldn't have to lift the throttle to shift and it'll automatically cut fuel/spark with the clutch pedal, but I haven't been brave enough to try it out yet with the engine wound up to 5,800rpm, it gives me shivers to think if it doesn't kick on what the rpm's would climb too. I should probably set it for a much lower rpm to really test it out.

    [​IMG]
     
  15. elagache

    elagache Platinum Level Contributor

    Do you have an onboard data logger? (Re: TheSilverBuick's 1977 Skylark)

    Dear Randal and V-8 Buick fans of high-tech,

    [​IMG] . . . Golly! and you did all that hauling a heavy trailer? . . . . [​IMG]

    Seriously, I'm curious about your very elegant graph. So do you have an onboard data logger so you can monitor what is going on at any time?

    Curious minds want to know! :)

    Cheers, Edouard :beer
     
  16. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    A fine feature of the Megasquirt 3 is an onboard SD card for datalogging. It doesn't log all the possible variables, to get everything requires a computer. I have a simple button to push that turns the logging on and off. So if it's doing something goofy, running funny, or I find myself at a suitably empty stretch of rural road and want to do some adhoc testing, I just push the button, a green light comes on telling me it's logging and I proceed. Then when back home I plug the laptop in and download the datalog. The SD card logging gets the most important basics recorded, 30-something variables(?), where the laptop is capable of logging every variable it's processing, which is a ton (think one VE map per cylinder, one spark table per cylinder, injection timing, staged injection so two injection timing maps, four speed sensor, and dozens of other things if you wire them up). It can be programmed to come on above certain rpm's, or throttle position, etc, so if you want a nice datalog every time you lay the pedal to the floor, it'll do that too (or if you worry you may forget to turn datalogging on at the track, these type of settings will make sure it's recording when going down the track).
     
  17. elagache

    elagache Platinum Level Contributor

    Advantage Megasquirt 3 (Re: TheSilverBuick's 1977 Skylark)

    Dear Randal and V-8 Buick fans of high-tech,

    That is definitely a nice feature. There is always an advantage to getting an early start in a given technology and Megasquirt is probably getting a boost from its open source aspects. So hat's off to the system you choose.

    FAST does have a available data logger. I'm not sure it makes any sense for me to get it though. Still, I'll look into it. Looking after all only costs time - not money! :dollar:

    Cheers, Edouard :beer
     
  18. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Not a whole lot going on other than driving it regularly. What do you do when the wife has the truck and need to make a run to the dump? Hook up the Drag Week trailer and take care of business!
    [​IMG]


    I don't have a car project thread for my '72 Centurion, mostly because it just languishes and slowly gets worse, but it's still a great car to go cruising around town in during the summer. This week I finally decided to dust it off and pull it out. It's just a reliable peach of a car though too. Put the battery charger on it over night, even though the lights still came on when the doors were opened I figured the battery was likely low after being parked for 9-10 months, then the checked the fluids and all were still topped off and looked clean, so put just a splash of gas on the top side of the Q-jet and it fired right up. Settled into an easy high idle which I let run for 3 minutes or so and gave the throttle a quick tap and the idle dropped easily to ~700rpm and it just runs like a Swiss watch.
    [​IMG]

    Decided to take a cruise across this small town and go out to dinner.
    [​IMG]

    The wife says riding around in it makes her feel like a Hollywood celebrity :cool: And true to form, despite what it actually looks like, in the five minute drive had one guy compliment the car while sitting at a stop light. After dinner, and sunset, it was still about 70F out so we made a loop around town just enjoying the experience. Some day I'll sand it down and do the body work it needs, as well as repair the rear window guides and a half a dozen other things it really could use. Bought it for $2500 with a blown up engine, rebuilt an engine for it, and installed a new top on it, and that is really all I've done to it in the last 15 years. Drove it daily through most of college and a few years after.
    [​IMG]
     
  19. elagache

    elagache Platinum Level Contributor

    What you need is . . . . (Re: TheSilverBuick's 1977 Skylark)

    Dear Randal and caregivers of V-8 Buick members of the family, . . . .

    [​IMG] . . . Hold it right there! I see your problem! What you need is a Buick wagon!! . . . [​IMG]

    Seriously, glad that da' Silver Buick is more than willing to earn her keep when needed!

    I do hope you eventually find enough time to give that Buick some more 'luv, but I'm glad you were able to take it out and you and your wife were able to enjoy it! :)

    Cheers, Edouard :beer
     
  20. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Yesterday I did a test of Megasquirt's flat shift feature to see how well or poorly it works. The idea behind the flat shift feature is that you can leave the gas pedal planted to the floor when you clutch in to shift and it'll rev limit with fuel and/or spark (how ever you want to set it) to a desired rpm. This of course requires a switch on the clutch pedal adjusted appropriately to work well. I just have it hooked to a stock neutral safety switch. Because I don't trust it yet I set the lower limit at 3500rpm so I don't have to be above 5,000rpm, on the throttle and clutched in, you know, in case it didn't work :pray: Turns out I still chickened out a bit on trusting it, lol, but it did appear to do what it's supposed to do. At the lower rpm/throttle position there appears to be about a 200-300rpm spike before it takes over, that is likely the clutch disengaging before the switch is triggered. I need to look at the switch and see if it can be adjusted some, or make a new switch. Not a bad data point to start with though.


    Typically my logs show I completely lift off the throttle when shifting, so this is some improvement on that. I "thought" I didn't lift at all, but the log doesn't lie, my sub-conscious got the better of me. It also shows timing being pulled for traction management all through first gear and pedaled it some into 2nd (the rear started to kick out) and right into 3rd.
    [​IMG]
     

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