Wiring up my TPI (From '89 FFB) Any input Knuckle Dragger?

Discussion in 'High Tech Retrofits' started by Penix, Oct 15, 2007.

  1. ULTM8Z

    ULTM8Z Veteran Member

    Messages:
    9,034
    Likes Received:
    286
    Joined:
    May 19, 2000
    Location:
    Los Angeles
    John,

    I'm not going to pretend that I know anything about blown applications because I've never had one. But my guess would be between 9 and 9.5:1. I know people supercharged factory LT1 Camaros/Corvettes/Firebirds and they're all running 10.5:1- but I can't speak to any problems they may have had while doing that. I'd imagine that it would also come down to how much ignition timing you could run based on the CR you have.
     
  2. ULTM8Z

    ULTM8Z Veteran Member

    Messages:
    9,034
    Likes Received:
    286
    Joined:
    May 19, 2000
    Location:
    Los Angeles
    I love the TPI computer. The only thing it's deficient in IMO is that it's not sequential injection. But the amount of fidelity you have in tuning the fuel and spark for any driving condition is still more than adequate for 95% of street applications. And for reprogramming, Tunercat makes things very user friendly and very intuitive for the beginner to get his feet wet (it's WAY better than trying to work in hexidecimal). They even have a Real Time tuner that works with an EPROM emulator such that I can drive around with a lap top, pull over to the side of the road, make a tuning adjustment and then keep right on driving (I don't even have to shut the engine off). It also allows you to do some cool things- for instance, with my Miniram being so close to an LT1/LT4 manifold I figured why am I going to reinvent the wheel and spend countless hours tuning fuel and spark only to probably end up at the same point as GM did with their LT1/LT4? So I managed to get hold of the LT4 Vette calibration and basically used Tunercat to literally copy and paste LT4 tables and constants associated with fuel/spark right into my TPI calibration. Now the car runs 99% perfectly with GM's factory cal (I just had lean out open loop a little- couldn't believe how rich GM runs these things).

    Also, for a while I've been toying with the idea of transitioning to a 94-95 Camaro/Corvette PCM. It's still OBD-I, but it has sequential EFI. The nice thing is that after I did the schematic comparison, I found that the wiring harness schematic and sensors are nearly identical to the TPI (right down to the wire colors!). Would just have to route new wires into the harness for the sequential injection and then extract the pins from the TPI ECM connectors and repin them into the LT1 PCM. The only somewhat complicated aspect of this swap would be dealing with the Opti-Spark. Though I'm aware of people having transplanted the Opti guts into a small cap HEI distributor.

    I don't know... future project ideas that will probably never come to fruition. :whine:
     
  3. John Wright

    John Wright Veteran Member Lifetime Gold Member

    Messages:
    14,610
    Likes Received:
    189
    Joined:
    Aug 9, 2002
    Location:
    Rustburg, Va
    Mike, I hope to get a handle on how these EFI things work, one of these days. The Tunercat sounds like a neat tool...especially since you stated "that it was very user friendly and very intuitive for the beguinner to get their feet wet".....boy if that doesn't describe me to a "T", then I don't know what does......LOL

    I feel like most of the time, if I can figure out how something works, then I can troubleshoot and work on it...but when the mystery is there, I get lost very easily trying to figure things out...the computer is a mystery to me at the moment, but once I figure out what all it does and how it thinks, I can get a grip on how to use it....LOL, (if all that makes sense).

    You guys have been a great help all ready....I just keep reading and one day it will all click for me....
     
  4. ULTM8Z

    ULTM8Z Veteran Member

    Messages:
    9,034
    Likes Received:
    286
    Joined:
    May 19, 2000
    Location:
    Los Angeles
    Makes perfect sense. That's how I was before I started getting into tuning. But again, don't let it intimdate you. If you know how engines work mechanically, once you start looking at the tables in Tunercat, the whole shroud of mystery surrounding the inner workings of EFI starts disappearing very quickly.

    For instance, the spark tables. It's basically a matrix that has manifold pressure across the top (from 20kPa to 100kPa) and RPM on the left (from 400 rpm to 6500 rpm). In the middle of the matrix are the spark advance values. So for any given RPM and MAP, you have an advance value. So instead of a 2D advance curve that's characteristic of a mechanical vacuum advance distributor, you have a 3D spark map. Very intuitive, but much more fidelity and tunability than a carb setup.

    There are still some Tunercat functions that I don't even understand yet, but I figure if the car is running great with the factory presets in them, I'm not going to worry about them.
     
  5. BonzoHansen

    BonzoHansen Administrator Lifetime Gold Member

    Messages:
    19,242
    Likes Received:
    677
    Joined:
    Jun 1, 2005
    Location:
    Scott from Hamilton, NJ

    A guy in our club is tech support for HPT. Neat software.
     
  6. John Wright

    John Wright Veteran Member Lifetime Gold Member

    Messages:
    14,610
    Likes Received:
    189
    Joined:
    Aug 9, 2002
    Location:
    Rustburg, Va
    http://www.tunercat.com/tnr_desc/do_tc.html


    This looks like something I can learn to use....I was also looking at the pocket programmer to burn PROMs....very cool stuff. The RT Tuner allows real time programming so you can program on the fly....another cool deal.
     
  7. ULTM8Z

    ULTM8Z Veteran Member

    Messages:
    9,034
    Likes Received:
    286
    Joined:
    May 19, 2000
    Location:
    Los Angeles
    John, I'm running the XTronics Pocket Programmer as well as the RT Tuner and PROM Emulator. They're great tools. Also, John over at Tunercat (I used to work with him when we were both at Edelbrock) is very responsive and has added many parameters to the ECM definition files at my requests- i.e., I'll read about some new tuning parameter at thirdgen.org and then e-mail John to add that parameter to the ECM definition file. Within a couple of days, he'll send out the updated file to me. It's awesome! :D
     
  8. John Wright

    John Wright Veteran Member Lifetime Gold Member

    Messages:
    14,610
    Likes Received:
    189
    Joined:
    Aug 9, 2002
    Location:
    Rustburg, Va
    I just need to get my car running again at the moment, but this stuff looks like it will be on my want list in the not too distant future......
     
  9. green 1977

    green 1977 Veteran Member Lifetime Gold Member

    Messages:
    3,784
    Likes Received:
    91
    Joined:
    Aug 18, 2003
    Location:
    On Wisconsin!
    I love your optimism John, with that attitude it won't be long and it will be running:)
     
  10. John Wright

    John Wright Veteran Member Lifetime Gold Member

    Messages:
    14,610
    Likes Received:
    189
    Joined:
    Aug 9, 2002
    Location:
    Rustburg, Va

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.