The Break Down of a '69 Pontiac OHC inline six

Discussion in 'The "Other" Bench' started by TheSilverBuick, Dec 20, 2010.

  1. SteeveeDee

    SteeveeDee Orange Acres

    I'm at a loss in understanding how this makes power. I'll be paying attention to this.
     
  2. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Combination of inertia and harmonics. The overly simplified version is the ports are tapered and the way it works as the air moves towards the valve it picks up speed, and that speed pulls more air, and as the cylinder is approaching full and air speed would be dropping off, the inertia of the air in the runner keeps pushing to get a bit more air/fuel into the cylinder. If the runners were short then that inertia would be lost as the air would be pulled another direction by a competing cylinder. Then the length I went with, in theory, should get the intake valve and pumping harmonics as such that around 5,500rpm there should be an extra pulse of high pressure (higher air density, more power potential) running through an open intake valve.

    Then the side benefit of not being attached to the exhaust manifold for a cooler air charge as well as it will really allow me to lay over the injectors to spray fuel towards the intake valve and/or down stream of the runner, which is best for atomization as well as the flow assists in pulling/pushing air into the cylinder, versus just spraying into the port perpendicularly and hitting the runner floor and needing the air to vaporize it as it passes by.
     
  3. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I've just been driving the car all month. Also the transmission has been shifting soft since the TCC solenoid came loose, so I'm guessing I toasted some clutches from pressure loss. Practically drives like a normally shifting transmission now despite the harsh shifting kit/holes I put in it.

    After work today or tomorrow I plan on putting the Firebird up on jackstands in the barn to begin the transmission pull to see what is going on inside of it. With that, right before Christmas two front rotors showed up, so I can possibly also switch out to disc brakes while it's up in the air along with swapping out the rear axle for the 8.5" with 3.42 gears and an honest limited slip rear end. While I have the front and rear brakes apart, I'm going to look at adding a hall sensor to read the back side of the wheel studs to use as a vehicle speed sensor. Should only require drilling a hole in the dust shield and adjusting a threaded sensor with two nuts holding it place...

    To shift gears a bit, I got a Raspberry Pi mini computer for Christmas and am going to attempt to make a digital display in the Firebird similar to what I have in the Skylark but not yet go to the extreme of replacing the dash cluster. This will be a round one so to speak. If it works out well then I will try to eventually expand to replacing the cluster with a digital display. The primary hangup is my inability to use Linux :( But, figure it's only a matter of time before I figure it out enough.

    [​IMG]

    Goal one is to simply get it to start up and run Tuner Studio, from there I can expand on the idea.
    What I am thinking of doing after I get it operational is getting a 7" touchscreen for it (they seem to be less than $75!?!?) and replacing the generic panel with the Arrowhead on it with a touchscreen displaying various engine vitals. Interestingly enough, when I requested quick keys to change the display layout in TunerStudio for the Skylark, the programmer also added screen swiping at that time to change display layouts when using touch screens. So "in theory" I can have various gauges on there, but simply reach over and swipe left or right to have different data show up, or gauges with different warning light thresholds, etc. And being rectangular, means a different layout than I am using in the Skylark :)

    [​IMG]

    The panel is 2.5" by 4.5", but I don't see any issues with fitting a 7" screen back there, which I believe the dimensions are 3.9"x6.2". That would make the screen stick out approximately 3/4" a side in width and just over 3/4" top and bottom. Plenty of wiggle room. Mounting it firmly may require some creative work though.

    [​IMG]

    The goal is to make a squared up version of what is in the Skylark!
    [​IMG]

    So much to do!
     
  4. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    To bring this thread up to date.

    12-31-14
    1-1-2015
    1-2-2015
    1-3-2015
    1-8-2015
    1-10-2015
    1-11-2015
    Now the car sits in my work's parking lot getting snowed on because I figured we'd get only rain today, d'oh :pp
     
  5. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Some minor updates. Mostly just been toying more with using the Raspberry Pi as a car computer for a digital information center in my Firebird. I'm slowly learning more about Linux (retarded DOS) as I use it more and more. Otherwise, I've been driving the car around and am pretty happy with how it shifts and drives with the 3.42's and glad to be rid of the spool.

    I've also been looking through Tuner Studio's high speed logger settings to graphically see where various things happen in 720 of crank rotation. Apparently the program cannot easily display this information together despite collecting it all at once, so I'm putting it in Excel to see. There are two or three other charts I want to plot up as well, namely relating vacuum to crank degrees, and then hybrid between that plot and this plot.
    [​IMG]

    On the engine work side, I've knocked most the rust off the outside of the tube I'm going to use for an intake on the car, as well as trimmed it down to the length I need.
    [​IMG]


    Last night I did the first test run with the raspberry pi as a car computer for a gauges. On this run its a bit laggy, but I do believe there is room in configurations for speed improvements. Plus this was a visual ran through a remote desktop view, which may introduce lag. I think this was successful enough to warrant purchasing a 7" screen for it.
    [​IMG]


    A short video of the test run showing the current lag. A friend of mine is pretty sure it's the remote desktop (using my laptop to log into the Raspberry Pi) causing the lag, and the lag won't be there with an actual monitor connected.
    [video=youtube_share;mJbFnaJXQ-Q]http://youtu.be/mJbFnaJXQ-Q[/video]

    To humor myself, I've super-imposed the Tuner Studio screen to where I intend to install a 7" touchscreen behind the Firebird's dash. Where the option clock would go.
    [​IMG]
     
  6. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    To continue the onward march out into left field.

    I've got the Raspberry Pi booting to a small screen and with TunerStudio, though I have not yet tested it in the car because I haven't gotten a car power supply for the screen.
    [​IMG]

    I've welded up the runners, and unfortunately the one on the far right is upside down. I didn't catch that until mounted the plenum tube and it was not level. I'm not overly worried about it, it's more aesthetic than anything else, and once in the car I don't think I'll even notice it.
    [​IMG]

    Tack welded together. The difficult part will be sealing it up for sure. I've been experimenting with brazing, or I may punt and simply pour a bunch of non-hardening epoxy on it (or both...). As long as the final product seals I'll be happy, regardless of how it looks. I measured the tube and runners so it should land between the wiper motor and master cylinder.
    [​IMG]

    Here is where the "oops" is apparent. On the plus side it will make routing the throttle cable easier because it is lower back at the firewall. I haven't decided yet about what I'm going to do about the flairs. I may leave them, I may trim some corners out and spot weld them on, or I may make three rectangular pieces with a nice curve to attach to each port pair. I'll likely try the third option first.
    [​IMG]

    The head I'm bolting it onto has a gasket match port job, so I'll do a gasket match port job to this intake as well.
    [​IMG]

    Also got these really slick steel injector bungs from CNC Dude on the inliner.org forum. The idea is to use the same setup as my friend did on his Ford intake. The issue I ran into with the stock intake was the injectors hit the throttle body/carb when laid over too much. This isn't the case here, so I'm going to lay them over at least 45. I haven't decided how close to the flange I'm going to put them since I can't reasonably angle them at the back of the valve due to the ports pointing away from each other in the head.​
    [​IMG]

    His setup on the Ford intake for drilling and setting the injector bungs into place.
    [​IMG]
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  7. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Some more updates.

    And today :)

    I did the first in car test with the Raspberry Pi, and other than the expected slow boot up and the cursor in the way, the test was successful!


    I need to solve the cursor issue and I still want to work on the boot up time, but I think this is a pretty good test of the proof of concept. I will probably try and make the desktop background black so it shouldn't flash so white on start up.


    [video]https://youtu.be/PuRptJNBIMA[/video]


    As a reminder of what I'm ultimately going for.
    [​IMG]
     
  8. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    A few updates. I drove the car to Salt Lake City last week (~560 miles all in). The fuel mileage surprisingly was unchanged from running the 4.56 gears =/ But I partially attribute it to the 80 mph speed limit and the hellacious winds that were blowing across the salt flats there and back. I think it just keep the engine working hard. It got 19mpg, which is essentially what I got before the gear swap.

    After the trip I made some changes to the fueling strategies with the injection. I've switched it to finish injecting fuel just before the intake valve opens at lower rpm and throttle. I've been running only injecting fuel when the intake valve is open and as much as possible while the exhaust is closed. I also re-ran the compression tests, and the worse one is 12% off the highest one, but its always been that way (not surprising how crappy the bores and valves look), but I decided to take those numbers and put some minor fuel trims in each of the cylinders figuring if they are not all pulling the same amount of air they don't need the same amount of fuel. I'm tempted to wing in the ignition timing trims too. Its practice if nothing else.

    I also noticed I had my TPSdot(sensitivity) set at a ridiculously high 120, so I lowered it to 20 and not surprisingly it got more zing off idle, its the equivalent to changing the accelerator pump arm or linkage on a carb.

    I'll do some datalogging this week going to work and see if I can further optimize the tune at cruising speeds.

    Flying by the Bonneville Salt Flats.
    [​IMG]


    Worked on the intake some more over the weekend as well. Still needs lots of finishing work, but it's progress!

    First my template for drilling and eventually holding the injector bungs. The two ratchet straps and the claps working together held the angle iron in place surprisingly tight.
    [​IMG]

    Drilled out the runners and fit the steel injector bungs. It took a little finishing grinding to get the shape needed to actually fit them in to place.
    [​IMG]

    I will have to cut the angle iron up in a way that I can remove it after tack welding the bungs to the runners.
    [​IMG]

    At a 45 angle the injector bungs fit very well.
    [​IMG]

    More clean up work will need to be done after they are welded in. I may to a rough cut on the bungs before installing them to reduce the amount of grinding required in the port.
    [​IMG]

    [​IMG]

    I also bought a bulk supply of the sealer I'm going to slather over all the welds =P
     
  9. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    The wife and I are heading out for the Car Craft Anti-Tour later today. Going to take a leisurely drive to the mountains, then out to the coast before the start then up to Morro Bay for the car show there (part of the Anti-Tour). It'll be a a bit over 1,500 miles when all said and done. Hoping for a trouble free drive and a fun few days :) I wanted to visit the sailing rocks in Death Valley on the return, but it appears to be a ton of dirt road and actually more worrisome is running out of gas! Will have to check that off the bucket list another time.


    [​IMG]
     
  10. John Brown

    John Brown On permanant vacation !!

    I would love to make the trip from Ely to Vegas one more time in. Our family took a trip "out west" when I was but a young un, and I still remember stopping for breakfast at a small mom and pop restaurant in Caliente, NV. The whole town was on one side of the highway and the other side was nothing but a bunch of railroad tracks. Luckily, now with the internet, I can view that trip without leaving home. It's sure beautiful country out there. Wish I could be riding along. Be safe.
     
  11. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I do love our desert mountain scenery.

    Through the magic of black duct tape I temporarily installed the Raspberry Pi and screen. I have it hooked up to a battery power source so it doesn't reset each time I turn the car off, just have to remember to shut it down at the end of the day.
    [​IMG]
     
  12. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Haven't updated this here in a long while. Looking at the last post, I was just about to leave on the Car Craft Anti-Tour and sadly the car never made it due to a failed wheel bearing 300 miles into the drive :( But I converted it to disc brakes the following weekend because I had the parts sitting on a shelf ready to go and it was quickly back on the road. I'm going to cut and paste some posts from the OHC forum I'm on to bring this thread up to date :)

    May 3.
    June 13. I drove the car out to the little town 25 miles outside of Ely that has a certified trucker scale. I was quite pleased with its actual weight compared to what I expected.

    June 20. Drove to a "Run Whatcha Brung" event at an airport in the next small town over. I was disappointed by the actual ET, but given the elevation and humidity that day I ended up being surprised how well the numbers back calculated to what I expected the engine to make. Would like to run it at sea level in some decent air.
    July 22. Turns out I don't need to buy a MicroSquirt as I actually have a spare Megasquirt II currently that will work from de-EFI'ing my Thunderbird a little over a year ago to scavenge parts off it for the Firebird build.
    October 9. I now have the Raspberry Pi working as intended and set up so I can switch between it running on battery power and staying on or come on and off with the ignition key.
    October 14. The car is running good.
    November 30. I skipped a few R&D posts where I drilled a hole in a Buick 455 exhaust manifold and then MIG welded a plate over it to see "how" it'd weld. So here I got bold and cut a bigh chunk of the exhaust manifold's intake cross over off and welded some plates to it. Including spending time in the oven in my barn for heating and cooling. I also skipped a few posts about different assembly stages of the intake manifold.
    Then yesterday, December 11.
     
  13. John Brown

    John Brown On permanant vacation !!

    I for one, enjoy reading the updates. :TU:
     
  14. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Skipping a few intermediate details of the fuel rail and painting, I bolted it to the engine yesterday.

    I've hose clamped a piece of aluminum trim to the top of the intake to help hide and draw eyes away from my welding, lol.
    [​IMG]

    [​IMG]
     
  15. SteeveeDee

    SteeveeDee Orange Acres

    I'm dissapoint! Here I was thinking that the welds were pretty nice! Good looking little hot rod, I like it.
     
  16. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    You're a saint :pp :beer
     
  17. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Few minor updates. Its been cold and snowy here so haven't had much motivation to do a whole lot of work on the car since I can't drive it out there anyways. Also the throttle cable I ordered never showed up so the seller is sending another one.

    I got all the pieces for the air filter except a few hose clamps to really hold it in place. I trimmed about a 1/4" off the elbow so it clears the radiator and radiator hose just fine. It's kind of hanging in the photo but should clamp up nice.
    [​IMG]


    Then today:

    In the background of things I've been working on trying to make a reasonable attempt at checking the flow of these heads using my spare block and David Vizard's shop vac setup (http://www.musclecardiy.com/cylinder...-heads-part-3/) and if I get reasonably repeatably result I'll see about having a cfm calibration plate made, but in the mean time I've wanted to work on a proof of concept as well as see if the $8 USB camera would work well enough to "watch" wet flow. Today's tests were interesting to say the least!


    I'm still trying to figure out how to best seal the bottom of the chamber with the shop vac. My first, and only, test so far was with a cut up nerf foot ball with a hole sawed hole in the middle for the shop vac fitting. Because I wasn't looking for specific repeatable numbers yet I just stuck the camera cord through the hole too. When I got it reasonably positioned and turning the vacuum on I learned a few things. One it simply sucked the whole thing to the top of the chamber and two the test valve springs I am using are not strong enough and both the intake and exhaust valves are pulled off their seats. So I need stronger springs and to work on the seal still. The second thing I learned is the camera isn't quite good enough to see how water mist flows into the chamber when spraying water at the port. And the third thing I learned is when the shop is 10F, and the block and head probably is too, ice builds up! LOL! I'll call this a "COLD flow test" lol.


    The test set up.
    [​IMG]


    Now the ice may have been as much a blessing as a curse as it has there frozen the water (fuel?) spray direction/pattern.
    [​IMG]


    So you can see why I opened it up on the sparkplug side of the intake valves (old photo).
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    I found it interesting that there was no ice build up on the cylinder wall side of the intake port or chamber. Basically confirms everything I've read.
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    A better view of the sparkplug. The ice had built up enough to keep the intake valve from seating.
    [​IMG]


    I tried taking some video's of the water flow, but all of them have water hitting the camera and blurring out (possibly icing up the camera..). So I decided to put a cam housing on with a 1bbl cam in it and video the valve action. The chamber is already iced over but it's still kind of neat to see. The overlap between the intake and exhaust is very minimal.
    [video=youtube;g8FAxhOTcx0]https://www.youtube.com/watch?v=g8FAxhOTcx0[/video]




    I've built a 8ft tall manometer with $15 worth of tubing and measuring tape and a spare piece 8ft white baseboard trim, but I won't put water in it until I'm sure of the rest of the test rig AND I know it won't freeze up!
     
  18. OHC JOE

    OHC JOE BUILDIN A 1970 GSX CLONE

    This thing is wicked...keep it up....did you every talk to Richard in pahrump Nevada..he is a big Ohc guy
     
  19. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    Thanks! Yes I've been to his house and bought a few parts from him. A bit eccentric.
     
  20. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    I haven't updated this thread here in a while. Here are some highlights.

    Feb 27.
    March 4th.

    March 8th.

    March 8th.

    March 31st.
    April 1st, I'm the fool :bla:

    April 2nd.

    April 3rd.
    April 3rd.

    I've started messing with the Raspberry Pi again, I got a quicker one to eventually swap in and want to delve into some python scripting as well to quicken up the boot time and control when it would shut down (like 4 hours after key off, etc).
     

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