Fixing "the foot" thought?

Discussion in 'Before Black (non-SFI) Tech' started by ShawnR, Aug 25, 2017.

  1. ShawnR

    ShawnR
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    I will be swapping out my turbo housing in the next few days to add a meth injection kit and am playing with an idea. It has been discussed about how that air comes out of the turbo and hits the wall at the bottom of the foot right as it goes into the intake.

    Has anybody ever tried adding a slight radius on the inside so things might flow a little smoother?
    I was thinking of building up the orange area with JB weld (or something) . It would narrow the passage slightly, but in my mind, it would help the airflow keep moving without having to do that right angle turn.

    foot1.jpg


    Thoughts? I have a spare housing so if it really sucks, I can always go back to stock.
     
  2. WarWagon

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    Try anything you want on a spare, easing the turn sounds like it would help on on hand on the other hand you loose volume in the bend area. The best solution IMO for the foot mount is to get rid of it entirely along with that horrible intake manifold it mates too.
     
  3. blacknight80

    blacknight80
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    I thought a big issue was the size of the hole in the intake. It bottle necks to much.

    Sent from my SM-G930W8 using Tapatalk
     
  4. b4black

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    I'm not sure that's the 'wall' people are referring to. I think it's the wall the is made up by the bottom/floor of the intake manifold. As the air/fuel charge leaves the turbo foot, it quickly hits the intake floor and needs to spread out to each cylinder.

    Personally, I'm not sure that's the biggest issue. Or at least not the first thing to get in the way. I think the biggest issue is an overactive timing retard system. Can you go WOT for a ¼ miles without any knock? What gauges have you added?

    I'm curious about you meth injection system. I'm guessing you're planning to install the nozzle in the turbo outlet. I was worried to adding it here because I was unsure about getting even distribution among the six cylinders. How much pressure does the pump put out? How are you triggering it to turn on?
     
  5. ShawnR

    ShawnR
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    I never really race it, but it has the stock knock sensor on it now, and will fall flat on its face if I get a little too aggressive. I don't drive much, so lately I have been running the 110 octane / 93 octane mix and that seems to take care of the detonation problem. I am only running about 12lbs of boost most of the time. There is a heck of a difference even just bumping it up to 15lbs.

    I bought this kit a month or so ago in preparation for a new engine (AEM Electronics Water/Methanol Injection Kits 30-3300) from the for-sale section. It has a 200 PSI pump and fits into a fitting right on the side of the foot as it goes into the intake. It has some little sensor thingy where you set a start boost pressure and max boot pressure and it is supposed to ramp up flow in between.

    I have a spare Weiand intake too, and have played with how to make it work, but I can't come up with anything that will still fit under the hood.
     
  6. b4black

    b4black
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    You have an '83 T Type right? (You might want to add a signature)

    If so, then you should look at a Casper's knock gauge. I think you'll find that even when it's not falling on it's face, it's still knocks quite a bit and that pulls a lot of timing. '83s use the same knock sensor as 84/87, so this will work fine:
    http://www.casperselectronics.com/c...duct/product&path=7_53_54_10_14&product_id=31

    You might want to also consider a wideband O2 sensor. Have you ever changed the secondry rod hangers?
     
  7. ShawnR

    ShawnR
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    Both of those are on the short list to purchase. I have a J&S Safeguard, but I haven't been able to get John to sell me the wiring plug for it. It is an older model and I just need the plug and instructions. I'll email him again.

    Rod hangers, I know what it is, but didn't really know you could change it and what the benefit would be. Lifts the rods higher when the butterflies open up? Existing rods on new hanger, or I need new rods too?

    I'm picking up a 109 block tomorrow morning to start the EFI build, but realistically, it could take a year or more, so I would like to get this system working to it's best potential.
     
  8. oddmonte

    oddmonte
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    You can get 12-15 psi of boost? I can only get 7-10. Most of the time I only get 5 or less.
     
  9. ShawnR

    ShawnR
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    That would probably be your wastegate. I initially added an additional spring to mine with a piece of wire to the flapper. Just kept shortening it until I found a good tension. If it is tight, I have no problem hitting 20lbs (that's a bad thing!).

    I now use an RJC boot controller and that seems to work pretty well.

    As for the whole upgrade idea, the pics show what I was thinking about.


    IMG_20170827_210119.jpg

    It is a good 3 inches higher than the stock height, so I don't think it would clear the hood anyway. If I were willing to cut in the manifold, it could go lower (not gonna do that). I would need to fab up a top plate for the intake and a way to mount the carb flange to the turbo, but those are both doable.

    Would the quadrajet even provide enough fuel to run 20 psi?

    This is mostly just an exercise, but it really wouldn't be to hard and doesn't involve pulling the engine.
     
  10. WarWagon

    WarWagon
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    The Q-jet can and will supply enough fuel for 20+ psi. Remember any time you run a draw through configuration you have to use a turbo that has a carbon seal on the compressor but that is the only time.
     
  11. b4black

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    I run 19 psi on Qjet all the time. It's a 800 CFM carb that is good enough for 455 Big Block Buicks. :)

    I would recommend taking out the fuel filter in the inlet. The built in check valve was restricting flow for me enough to cause issues in the ¼ mile. I use an inline filter, but the fuel does drain done causing longer starts up are sitting for a few days.

    Low boost can be many things. If the secondaries aren't opening, that will limit you to about 6 psi. Make sure the upper air valves opening easily. Also check the spring on the secondary throttle shaft (driver's side)- mine was unhooked and the secondary throttles would not open. My throttle cable also bottomed out before they were completely open.

    Plugged catalytic converter (is you still have one) will limiit boost as well.

    I use a small turnbuckle to hold the wastegate shut when troubleshooting low boost.
    [​IMG]
     
  12. oddmonte

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    I did not know it was possible to get that kind of boost out of a draw through engine. I think my seal is out of my turbo. It uses a lot of oil. I have checked the carb out, replaced fuel filter and adjusted the waist gate. I could have cracked header, but I think most of my problem is the turbo. I am just trying to get through October 1 and then I am going blow through. Going to do a compression test once I have it tore apart and make sure it is not a engine problem.
     
  13. b4black

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    Low boost is unlikely the turbo. They either work or don't. When the seals go out, you either see oil in the downpipe or you see a lot of smoke after decelerating (high vacuum).

    If you have cast exhaust manifold, check the driver's side. The often crack between the rear two cylinders. I had one split in half when I bought the car. You can replace the driver's side with a non-turbo manifold.
     
  14. ShawnR

    ShawnR
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    Well, good or bad I went ahead and added a glob of JB Weld to the front "corner" where the airflow has to do a right angle. Since I don't have an intake temp sensor, I don't have any real way to know if it is actually going to help or not. It certainly feels to be a smoother transition.

    foot_1.jpg
    I am switching to the spare turbo housing because it already has a fitting in it for the meth injection kit (AEM 30-3300). It looks to be a pretty simple install and I can easily move it to the new engine whenever it is done.
     

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