Results 1 to 7 of 7

Thread: Turbo question for an '84 TD Max

  1. #1

    Array
    Status
    Offline
    Join Date
    01-24-2019
    Posts
    40
    Location

    Nevada
    Vehicle

    1984 Mitsubishi Mighty Max
    Engine

    4D55-T

    Turbo question for an '84 TD Max

    What's up everyone
    I have a question about the stock turbo;
    My '84 MM compressor housing is stamped tc05-10A but I have a wastegate. Everything I've read says the tc05 was only on the 83 non-gated.
    Have any of you seen this or am I looking at something that was hodgepodged together?
    My truck is also California emmission spec if that makes any difference.
    I likely need a rebuild or replacement (also read that the TD units are better and would likely go that route) so I am gathering as much info as possible.

    Another question I have is about exhaust size, whats optimal? I was talking with my buddy who's into theory and such with turbos. He said going to big is bad as removing all back-pressure, on an engine that doesn't have the high power output like current or performance stuff, would decrease the amount of tourque made by the boost (paraphrasing from memory). Thoughts?

    Thanks in advance
    -B

  2. #2

    Array
    Status
    Offline
    Join Date
    06-15-2014
    Posts
    4,263
    Location

    Adelaide, South Australia
    Vehicle

    1985 Mitsubishi L200
    Engine

    G63B
    The TC05-10A was used on Mitsubishi Raiders, Pajeros and L300 vans and there appears to be both waste gate and non-waste gate versions (google image came up with TC05's with waste gates so who knows). An engine does not need exhaust 'back pressure' but an engine manufacturer will try to find a compromise with exhaust size as they want a balance between low down torque and top end exhaust gas volume. I would get a better flowing turbo with a waste gate and go up 1/4" to 1/2" max for exhaust diameter. This should get the engine onto boost earlier and be able to keep up with exhaust gas flow on open throttle instead of strangling it. The main problem with the 4D55 is the turbo is too small for the engine and it runs out of steam quickly. I think you will need to figure out how to improve the fuel delivery curve as well. Better turbo + decent exhaust + fuel will vastly improve drivability.
    support the forum that supports you - join and donate to MightyRam50.Net Get perks and donations $15 USD and over receive official MightyRam50.Net window decals

  3. #3

    Array
    Status
    Offline
    Join Date
    01-24-2019
    Posts
    40
    Location

    Nevada
    Vehicle

    1984 Mitsubishi Mighty Max
    Engine

    4D55-T
    Hmmm, more fuel. Me thinks this means a search for a federal (or not California) emissions injection pump is in the future.
    So bigger or just better flowing? Does better flow make more low end torque or just more efficient thus being able to use what is made?
    This is all speculation right now as there are bigger fish to fry i.e. body work and grill, steering rebuild, finish center console, headliner and dash pad, clutch and transmission inspection and seal with rear main seal if its leaking.
    This list is growing as I type time to stop before I, squirrel!...

    Thanks geezer
    -B

  4. #4

    Array
    Status
    Offline
    Join Date
    06-15-2014
    Posts
    4,263
    Location

    Adelaide, South Australia
    Vehicle

    1985 Mitsubishi L200
    Engine

    G63B
    There should be a way to ramp fuel supply on the stock pump. I am not a diesel guy but there is always a trick to improving fuel output (like old school Saab 99 turbos - drill a hole in the side of the pressure regulator housing, insert allen key and turn it up, add boost - instant fun) As for turbos, bigger doesn't mean better. Another thing I'm no guru about. It seems the biggest gripe about the stock turbos on 4D55/56 engines is the turbo runs out of chuff before the engine does.
    support the forum that supports you - join and donate to MightyRam50.Net Get perks and donations $15 USD and over receive official MightyRam50.Net window decals

  5. #5

    Array
    Status
    Offline
    Join Date
    06-12-2015
    Posts
    121
    Location

    Owensboro, KY
    Vehicle

    1991 Dodge Ram 50
    Engine

    4D56-T
    You can get more out of the stock pumps for sure. For starters you can adjust the AFC on the top of the pump for earlier boost fueling. This doesn't give you any more than you would be getting, but it brings it on a lower boost pressures so you get better turbo/throttle response. You can find videos of people doing this on YouTube, it's a pretty easy think to do on your own. You can also try to advance the pump timing a little bit. Factory injection timing on these motors is something like 5* after top dead center, bumping that up a few degrees again helps with throttle response and gives a little boost in power, just don't advance it too far or you'll lose power and possibly hurt something. Again, there are videos inline for this. The other option for a stock pump is to adjust the full fuel screw, but this is risky as it can cause a runaway if you aren't careful. It isn't hard to do, but it can be hard to adjust it properly. I would try the other things first and then maybe do this. The stock pumps can handle a decent amount of air before this is necessary, if you start getting crazy with it you will want to upgrade the pump itself though.

  6. #6

    Array
    Status
    Offline
    Join Date
    01-24-2019
    Posts
    40
    Location

    Nevada
    Vehicle

    1984 Mitsubishi Mighty Max
    Engine

    4D55-T
    For sure, thanks a ton!

    I was just under the impression that the California pump was very limited on how much you can adjust it since I've read the'84 California pump is significantly different from the federal one.
    More research

  7. #7

    Array
    Status
    Offline
    Join Date
    06-12-2015
    Posts
    121
    Location

    Owensboro, KY
    Vehicle

    1991 Dodge Ram 50
    Engine

    4D56-T
    I don't know much about the California pumps, I thought the only changes were a few external accessories that could be removed.

Bookmarks

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •